Tag: Colon Cancer

Rising Incidence of Pancreatic and Colorectal Adenocarcinoma among Younger Populations

RR

SUMMARY: The American Cancer Society estimates that in 2025, about 67,440 people will be diagnosed with pancreatic cancer and 51,980 people will die of the disease. Detecting cancer at early stages can significantly increase survival rates and outcomes. Pancreatic Ductal AdenoCarcinoma (PDAC) is one of the most lethal malignancies, ranking among the leading causes of cancer-related mortality globally. A significant challenge in improving PDAC outcomes is its frequent diagnosis at an advanced stage, when therapeutic options are limited and prognosis is poor, with a 5-year survival rate of approximately 10%. Early detection is critical to expanding treatment possibilities and enhancing survival rates. Colorectal cancer (CRC) is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 154,270 new cases of CRC will be diagnosed in the United States in 2025 and about 52,900 patients will die of the disease. Even though the diagnosis of colorectal cancer in the US is dropping among people 65 years and older, the incidence has been rising in the younger age groups, with 12% of colorectal cancer cases diagnosed in people under age 50, leading to revisions in screening guidelines.

Study Objective
To provide an updated analysis of Annual Percentage Changes (APCs) in the incidence of pancreatic and colorectal adenocarcinoma across different age groups, focusing on younger populations, using data from the SEER database (2000–2021).

Methods
Data Source

  • SEER (Surveillance, Epidemiology, and End Results) database (22 registries, ~47.9% of US population)
  • Data updated through April 17, 2024

Study Design

  • Retrospective cohort study
  • Inclusion: Pancreatic and colorectal adenocarcinoma only
  • Exclusion: Rare pancreatic cancer subtypes (e.g., neuroendocrine tumors, mucinous cystadenocarcinoma)
  • The Rutgers University IRB exempted the study, and informed consent was not needed owing to the deidentified nature of the data.

Analysis

  • Yearly incidence rates per 100,000 population
  • Annual Percentage Changes (APCs) and 95% confidence intervals calculated for three age groups:
    • 15–34 years
    • 35–54 years
    • 55+ years

Results
Pancreatic Adenocarcinoma

  • Total cases (2000–2021): 275,273
    • 51.8% male, 87.1% aged ≥55 years
  • APC in 15–34 years: 4.35% (95% CI, 2.03–6.73)
  • APC in 35–54 years: 1.54% (95% CI, 1.18–1.90)
  • APC in 55+ years: 1.74% (95% CI, 1.59–1.89)

The APC for pancreatic adenocarcinoma in the group aged 15 to 34 year was statistically significantly higher than the APCs of 1.74 (P =0.007) for the group aged 55 years and older and 1.54 (P =0.004) for the group aged 35 to 54 years. The authors commented that the dramatic increase in the APC in the younger population suggests that close attention should be paid to this trend.

Colorectal Adenocarcinoma

  • Total cases: 1,215,200
    • 52.8% male, 80.4% aged ≥55 years
  • APC in 15–34 years: 1.75% (95% CI, 1.08–2.42)
  • APC in 35–54 years: 0.78% (95% CI, 0.51–1.06)
  • APC in 55+ years: -3.31% (95% CI, -3.54 to -3.08)

The APC for colorectal adenocarcinoma for the group aged 55 years and older was statistically significantly lower than the APCs for the group aged 15 to 34 years (P =0.001) and for the group aged 35 to 54 years (P =0.002). Most declines in colorectal cancer incidence was attributed to increased screening in older adults. Screening age was lowered from 50 to 45 years and may likely reduce future incidence in those aged 35–54.

Interpretation & Implications

Pancreatic Cancer

  • Though rare, pancreatic adenocarcinoma in young adults (15–34 years) is rising at an alarming rate.
  • Potential contributors: Smoking, alcohol, environmental exposures, though definitive causes remain unclear.
  • Clinician awareness is critical when evaluating younger patients with:
    • Abdominal pain
    • Weight loss
    • Anemia
    • Family history of pancreatic cancer

Clinical Insight: Historically, the above findings are not investigated in a young individual. It is therefore important to make sure a serious condition is not missed.

Colorectal Cancer

  • Increasing in younger groups, despite an overall declining trend.
  • This supports recent screening age revisions and highlights the need for vigilance in symptomatic young patients.

Limitations

  • SEER data covers ~47.9% of the U.S. population.
  • However, SEER is designed for accurate trend analysis and has reliable coding for common cancers like pancreatic and colorectal adenocarcinoma.
  • Restricting to adenocarcinoma improves the homogeneity and accuracy of the study.

Conclusions

  • Pancreatic adenocarcinoma incidence is rising in all age groups, especially in the youngest cohort (15–34 years).
  • Colorectal adenocarcinoma is increasing among younger individuals, while declining among those 55 and older.
  • Clinicians must heighten awareness of these trends and consider appropriate workups in symptomatic younger patients.

Key Takeaways

  • Pancreatic adenocarcinoma incidence rose >4% annually in individuals aged 15–34 years.
  • Colorectal adenocarcinoma also increased among patients aged 15–34 years.
  • Consider early imaging and endoscopic evaluations in symptomatic young adults.
  • Continue to support early screening efforts, especially for high-risk individuals.

Incidence of Pancreas and Colorectal Adenocarcinoma in the US. Bussetty A, Shen J, Benias PC, et al. JAMA Netw Open. 2025;8(4):e254682. doi:10.1001/jamanetworkopen.2025.4682

 

 

 

 

 

FDA Approves OPDIVO® Plus YERVOY® for Unresectable or Metastatic MSI-H/MMR Deficient Colorectal Cancer

RR

SUMMARY: The FDA on April 8, 2025, approved Nivolumab (OPDIVO®) with Ipilimumab (YERVOY®) for adult and pediatric patients 12 years of age and older with unresectable or metastatic MicroSatellite Instability-High (MSI-H) or MisMatch Repair deficient (dMMR) colorectal cancer (CRC). The FDA also converted the accelerated approval to regular approval for single agent Nivolumab for adult and pediatric patients 12 years of age and older with MSI-H or dMMR metastatic CRC, that has progressed following Fluoropyrimidine, Oxaliplatin, and Irinotecan.

Colorectal cancer is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 154,270 new cases of CRC will be diagnosed in the United States in 2025 and about 52,900 patients will die of the disease. The lifetime risk of developing CRC is about 1 in 23. The majority of CRC cases (about 75 %) are sporadic whereas the remaining 25 % of the patients have a family history of the disease. Only 5-6 % of patients with CRC with a family history background are due to inherited mutations in major CRC genes, while the rest are the result of accumulation of both genetic mutations and epigenetic modifications of several genes. Colorectal Cancer is a heterogeneous disease classified by its genetics, and even though the diagnosis of Colorectal Cancer in the US is dropping among people 65 years and older, the incidence has been rising in the younger age groups, with 12% of Colorectal Cancer cases diagnosed in people under age 50.

The DNA MisMatchRepair (MMR) system is responsible for molecular surveillance and works as an editing tool that identifies errors within the microsatellite regions of DNA and removes them. Defective MMR system leads to MSI (Micro Satellite Instability) and hypermutation, with the expression of tumor-specific neoantigens at the surface of cancer cells, triggering an enhanced antitumor immune response. MSI is therefore a hallmark of defective/deficient DNA MisMatchRepair (dMMR) system and occurs in 15% of all colorectal cancers. Defective MMR can be a sporadic or heritable event. Approximately 65% of the MSI high colon tumors are sporadic and when sporadic, the DNA MMR gene is MLH1. Defective MMR can manifest as a germline mutation occurring in MMR genes including MLH1, MSH2, MSH6 and PMS2. This produces Lynch Syndrome often called Hereditary Nonpolyposis Colorectal Carcinoma – HNPCC, an Autosomal Dominant disorder that is often associated with a high risk for Colorectal and Endometrial carcinoma, as well as several other malignancies including Ovary, Stomach, Small bowel, Hepatobiliary tract, Brain and Skin. MSI is a hallmark of Lynch Syndrome-associated cancers. MSI high tumors tend to have better outcomes and this has been attributed to the abundance of tumor infiltrating lymphocytes in these tumors from increase immunogenicity. These tumors therefore are susceptible to blockade with immune checkpoint inhibitors.

MSI testing is performed using a PCR or NGS based assay and MSI-High refers to instability at 2 or more of the 5 mononucleotide repeat markers and MSI-Low refers to instability at 1 of the 5 markers. Patients are considered Micro Satellite Stable (MSS) if no instability occurs. MSI-L and MSS are grouped together because MSI-L tumors are uncommon and behave similar to MSS tumors. Tumors considered MSI-H have deficiency of one or more of the DNA MMR genes. MMR gene deficiency can be detected by ImmunoHistoChemistry (IHC). NCCN Guidelines recommend MMR or MSI testing for all patients with a history of Colon or Rectal cancer. Unlike Colorectal and Endometrial cancer, where MSI-H/dMMR testing is routinely undertaken, the characterization of Lynch Syndrome across heterogeneous MSI-H/dMMR tumors is unknown.

Nivolumab is a fully human, immunoglobulin G4 monoclonal antibody that binds to the PD-1 receptor and blocks its interaction with PD-L1 and PD-L2, whereas Ipilimumab is a fully human immunoglobulin G1 monoclonal antibody that blocks Immune checkpoint protein/receptor CTLA-4 (Cytotoxic T-Lymphocyte Antigen 4, also known as CD152). Blocking the Immune checkpoint proteins unleashes the T cells, resulting in T cell proliferation, activation and a therapeutic response.

The present FDA approval is based on CheckMate 8HW, which is an ongoing Phase III, multinational, open-label, randomized trial evaluating Nivolumab plus Ipilimumab as compared with Nivolumab alone or chemotherapy, in patients with MSI-H or dMMR metastatic CRC. In this study, patients with unresectable or mCRC and MSI-H/dMMR status by local testing who had received 0-1 prior line of therapy were randomly assigned in a 2:2:1 ratio to receive either Nivolumab monotherapy (N=353), Nivolumab plus Ipilimumab combination therapy (N=354), or the investigator’s choice of chemotherapy (mFOLFOX6 or FOLFIRI with or without Bevacizumab or Cetuximab (N=132). Patients who had previously received two or more prior lines of therapy for unresectable or metastatic disease were randomly assigned, in a 1:1 ratio, to receive Nivolumab plus Ipilimumab or Nivolumab alone. In the Nivolumab monotherapy arm, patients received Nivolumab 240 mg IV once every two weeks for six doses, followed by 480 mg IV every four weeks. In the Nivolumab plus Ipilimumab arm, patients were given Nivolumab 240 mg IV plus Ipilimumab 1mg/kg IV every three weeks for four doses, followed by Nivolumab 480 mg IV every four weeks. The median patient age was 64 years and tumor location was in the right colon in two thirds of the patients. Treatments continued until disease progression or unacceptable toxicity in all treatment groups or a maximum of 2 years. The dual Primary end points were Progression-Free Survival (PFS) as determined by Blinded Independent Central Review (BICR) comparing Nivolumab plus Ipilimumab to chemotherapy in the first-line therapy setting, and PFS comparing Nivolumab monotherapy to Nivolumab plus Ipilimumab across all lines of therapy, in patients with centrally confirmed MSI-H/dMMR metastatic CRC. At a median follow-up of 31.5 months the results from the prespecified interim analysis (the primary analysis) showed that the PFS outcomes were significantly better with Nivolumab plus Ipilimumab than with chemotherapy (HR=0.21; P<0.001).

The researchers herein reported the first results from the other dual Primary endpoint of PFS for Nivolumab plus Ipilimumab versus Nivolumab monotherapy across all lines of therapy in patients with centrally confirmed MSI-H/dMMR metastatic CRC. Of all the randomized patients 296 in the Nivolumab plus Ipilimumab group and 286 in the Nivolumab monotherapy group had centrally confirmed MSI-H/dMMR status. With a median follow-up of 47.0 months, Nivolumab plus Ipilimumab demonstrated clinically meaningful and statistically significant improvement in PFS by BICR versus Nivolumab monotherapy, with a median PFS Not Reached (NR) in the Nivolumab plus Ipilimumab group, compared to 39.3 months for those on Nivolumab monotherapy (HR=0.62; P= 0.0003). The PFS rates at 12, 24, and 36 months were higher in the Nivolumab plus Ipilimumab group at 76%, 71%, 68% versus 63%, 56%, 51% for Nivolumab monotherapy. The Objective Response Rate (ORR) was significantly higher with Nivolumab plus Ipilimumab at 71%, compared to 58% with Nivolumab alone (P=0.0011). No new safety concerns were identified.

It was concluded that the CheckMate 8HW study met its dual Primary endpoints, with Nivolumab plus Ipilimumab demonstrating a statistically significant and clinically meaningful improvement in PFS compared to Nivolumab monotherapy across all lines of therapy in MSI-H/dMMR metastatic CRC. Moreover, Nivolumab plus Ipilimumab was associated with higher ORR, confirming its potential as a new standard of care for patients with MSI-H/dMMR metastatic CRC. The CheckMate 8HW study is a pivotal contribution to the treatment landscape of MSI-H/dMMR metastatic Colorectal cancer, providing compelling evidence for the use of Nivolumab plus Ipilimumab in the first-line and beyond.

Nivolumab plus ipilimumab versus nivolumab in microsatellite instability-high metastatic colorectal cancer (CheckMate 8HW): a randomised, open-label, phase 3 trial. Andre T, Elez E, Lenz H-J, et al. The Lancet. 2025; 405:383-395

Late Breaking Abstract – 2025 ASCO GI Symposium: Circulating Tumor DNA (ctDNA) as a Predictive Biomarker for Celecoxib Benefit in Stage III Colon Cancer: Insights from CALGB/SWOG 80702

RR

SUMMARY: ColoRectal Cancer (CRC) is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 154,270 new cases of CRC will be diagnosed in the United States in 2025 and about 52,900 patients will die of the disease. The lifetime risk of developing CRC is about 1 in 23.

It is estimated that approximately 30% of patients with Stage II or III CRC and 60-70% of patients after oligometastatic resection experience recurrence. Adjuvant chemotherapy for patients with resected, locally advanced, node-positive (Stage III) colon cancer has been the standard of care since the 1990s. However, not all patients with Stage III disease benefit from adjuvant chemotherapy. In the IDEA trial, the absolute Disease Free Survival benefit of adjuvant chemotherapy for the lowest-risk Stage III group and the highest-risk group was 8% and 20%, respectively, suggesting that a substantial number of patients with low-risk Stage III cancer can safely forgo adjuvant chemotherapy or be considered for treatment de-escalation.

More recent data suggests that platelets may play a role in tumorigenesis as well, through the release of angiogenic and growth factors due to overexpression of Cyclooxygenase 2 (COX-2). Aspirin and COX-2 inhibitors such as Celecoxib have been associated with a reduced risk of colorectal polyps and cancer in observational and randomized studies.

The CALGB/SWOG 80702 is a randomized Phase III trial conducted to determine if the addition of Celecoxib to adjuvant chemotherapy with Fluorouracil, Leucovorin, and Oxaliplatin (FOLFOX) improves Disease-Free Survival (DFS) in patients with Stage III colon cancer. Patients were randomized to receive adjuvant FOLFOX (every 2 weeks) for 3 versus 6 months with or without 3 years of Celecoxib (400 mg orally daily; N=1263) versus placebo; N=1261). In this study, the addition of Celecoxib for 3 years to standard adjuvant chemotherapy did not significantly improve Disease-Free Survival (DFS).

The present analysis evaluated the prognostic and predictive value of circulating tumor DNA (ctDNA) in identifying a subpopulation of patients in the above study, who may potentially benefit from Celecoxib therapy. A subset of 1,011 patients from the CALGB/SWOG 80702 trial with adequate biospecimen availability was included in this analysis. ctDNA status was assessed using a tumor-informed, clinically validated 16-plex multiplex Polymerase Chain Reaction Next-Generation Sequencing (mPCR-NGS) assay (Signatera(TM), Natera, Inc.). Plasma samples were collected post-surgery and before the initiation of adjuvant chemotherapy. Survival outcomes, including DFS and Overall Survival (OS), were analyzed using Kaplan-Meier estimates and Cox proportional hazards models.

Results:

  • Of the 1,011 patients with ctDNA data, 189 (18.7%) tested ctDNA-positive.
  • ctDNA positivity correlated with male sex, advanced T stage, and N2 nodal disease.
  • Patients with detectable ctDNA had significantly worse outcomes:
    • DFS: Hazard Ratio (HR)=6.52; P<0.0001
    • OS: HR=6.28; P<0.0001
  • Three-year DFS rates were:
    • 6% in ctDNA-negative patients
    • 8% in ctDNA-positive patients
  • Celecoxib did not significantly impact DFS in ctDNA-negative patients (HR=0.75; P=0.095, 3-year DFS: 87.7% vs. 85.5%).
  • However, in ctDNA-positive patients, Celecoxib was associated with a notable improvement in DFS (HR=0.59; P=0.004, 3-year DFS: 44.1% vs. 26.6%).
  • OS trends mirrored those observed for DFS:
    • ctDNA-negative group: HR=0.86 (P=0.49) with Celecoxib versus placebo.
    • ctDNA-positive group: HR=0.63 (P=0.028) with Celecoxib versus placebo.
  • Multivariate analysis confirmed a statistically significant benefit of Celecoxib in ctDNA-positive patients.

Conclusion: ctDNA serves as a strong prognostic biomarker for both DFS and OS in Stage III colon cancer. Furthermore, ctDNA positivity appears to predict a significant therapeutic benefit from adjuvant Celecoxib, suggesting its potential role in stratifying patients for COX-2 inhibitor therapy. These findings highlight the utility of ctDNA assessment in guiding adjuvant treatment decisions and optimizing personalized therapeutic strategies in colon cancer.

Clinical Implications:

  • Post-surgical ctDNA testing can help identify patients at elevated risk of recurrence.
  • Celecoxib may offer a survival advantage for ctDNA-positive patients when used alongside standard FOLFOX chemotherapy.
  • Further research is warranted to elucidate the role of ctDNA-guided treatment in personalizing colon cancer therapy.

Prognostic and predictive role of circulating tumor DNA (ctDNA) in stage III colon cancer treated with celecoxib: Findings from CALGB (Alliance)/SWOG 80702. Nowak JA, Shi Q, Twombly T, et al. J Clin Oncol. 2025;43(4):LBA14.

Late Breaking Abstract – 2025 ASCO GI Symposium: Personalized Neoantigen Vaccine in Metastatic Colorectal Cancer

RR

SUMMARY: ColoRectal Cancer (CRC) is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 154,270 new cases of CRC will be diagnosed in the United States in 2025 and about 52,900 patients will die of the disease. The lifetime risk of developing CRC is about 1 in 23.

The majority of CRC cases (about 75 %) are sporadic whereas the remaining 25 % of the patients have a family history of the disease. Only 5-6 % of patients with CRC with a family history background are due to inherited mutations in major CRC genes, while the rest are the result of accumulation of both genetic mutations and epigenetic modifications of several genes. Colorectal Cancer is a heterogeneous disease classified by its genetics, and even though the diagnosis of Colorectal Cancer in the US is dropping among people 65 years and older, the incidence has been rising in the younger age groups, with 12% of Colorectal Cancer cases diagnosed in people under age 50.

The DNA MisMatchRepair (MMR) system is responsible for molecular surveillance and works as an editing tool that identifies errors within the microsatellite regions of DNA and removes them. Defective MMR system leads to MSI (Micro Satellite Instability) and hypermutation, with the expression of tumor-specific neoantigens at the surface of cancer cells, triggering an enhanced antitumor immune response. MSI is therefore a hallmark of defective/deficient DNA MisMatchRepair (dMMR) system and occurs in 15% of all colorectal cancers. MSI testing is performed using a PCR or NGS based assay and MSI-High refers to instability at 2 or more of the 5 mononucleotide repeat markers and MSI-Low refers to instability at 1 of the 5 markers. Patients are considered Micro Satellite Stable (MSS) if no instability occurs. MSI-L and MSS are grouped together because MSI-L tumors are uncommon and behave similar to MSS tumors.

Checkpoint inhibitors have revolutionized cancer treatment. They are however not as effective in patients with “cold tumors” (MSS), as these tumors effectively hide themselves from the immune system and do not trigger an immune response following treatment with checkpoint inhibitors.

GRANITE is a personalized neoantigen immunotherapy designed to trigger a strong T-cell immune response against a patient’s tumor. A biopsy of the tumor is performed to identify unique mutations (neoantigens) present in the tumor of patients. An AI platform, EDGE, developed and designed by Gritstone Bio is able to identify critical T-cell vaccine targets, and predict which neoantigens are most likely to be recognized by the immune system of patients. The system has an 80% accuracy rate in selecting the top 20 most immunogenic neoantigens, most likely to generate an immune response in a given patient. The selected neoantigens are incorporated into a chimpanzee adenovirus-based primer vaccine and a Self-Amplifying mRNA (SAM) booster vaccine to train the immune system that leads to an induction of both cytotoxic T-lymphocyte and memory T-cell dependent immune responses, that specifically target and destroy the patients cancer cells that express these neoantigens. This vaccine (GRANITE) is administered via intramuscular injection alongside immune checkpoint inhibitors. Thus GRANITE primes the immune system to recognize and attack these tumors. This vaccine is customized for each patient based on the unique mutations of their tumor. In essence, GRANITE helps make the “cold tumors” visible to the immune system, potentially improving patient outcomes.

GRANITE immunotherapy regimen was evaluated in combination with Nivolumab and Ipilimumab, and compared to the combination of Nivolumab and Ipilimumab alone in a Phase1/2 involving patients with advanced metastatic solid tumors. This study demonstrated robust T-cell activation against targeted neoantigens with no dose-limiting toxicities, and over 50% of patients had a reduction in their circulating tumor DNA (ctDNA) and improved Overall Survival (Palmer CD, et al. Nature 2022).

GRANITE immunotherapy regimen is now being studied as first line metastatic treatment in a randomized Phase 2 trial, among patients with Microsatellite-Stable (MSS) Colorectal cancer patients. GO-010 is an ongoing Phase 2/3, randomized, open-label, multi-center study evaluating the efficacy and safety of GRANITE immunotherapy regimen in combination with Checkpoint Inhibitors (CPIs) as an add-on to Fluoropyrimidine/Bevacizumab as maintenance treatment, following first line therapy with FOLFOX/Bevacizumab, in patients with mCRC. In this study, 104 patients were randomized in a 1:1 ratio, and 67 patients were included in this treated analysis with 39 patients assigned to the GRANITE arm and 28 patients to the control arm. (36 patients withdrew from the study primarily due to early progressive disease or withdrawal of consent, and one patient has yet to begin study treatment). The vaccine manufacturing success rate was 100%. Both treatment groups were well balanced with regards to demographics, clinical characteristics stage, sidedness and presence of liver metastases. Approximately 75% of patients had liver metastases. For the Phase 2 portion of this study, the Primary end point being assessed is molecular response defined as 30% or more decrease from baseline in ctDNA. For the Phase 3 portion of this trial, the Primary end point is Progression Free Survival (PFS). Secondary end points for both Phase 2 and 3 include Adverse Events, Overall Survival (OS), Overall Response Rate (ORR), Duration of Response (DoR) and Clinical Benefit Rate.

Preliminary data from the Phase 2 portion of a Phase 2/3 study showed a positive early trend in PFS for GRANITE immunotherapy patients with a Hazard Ratio (HR) of 0.82 in all patients, HR of 0.52 in high-risk patients1 (more than 90% with liver metastases). The median PFS was 12 months with GRANITE immunotherapy versus 7 months for the control group. Long-term ctDNA responses aligned with positive PFS trend favoring GRANITE immunotherapy patients versus control patients.

In the high-risk group, between first blood draw (time of randomization) and last blood draw (most recent study visit), the ctDNA shifted from high (more than 2% VAF-Variant Allele Frequency) to low (2% or less VAF) in 56% of patients treated with GRANITE immunotherapy versus 22% of control patients. Progressive disease was observed in 44% versus 78% respectively, within this group.

In the low-risk group of patients whose ctDNA was negative after induction chemotherapy, sustained ctDNA negativity was observed in 67% of GRANITE immunotherapy recipients versus 38% in the control patients. Progressive disease was observed in 11% and 38% of these patients, respectively. GRANITE immunotherapy was well tolerated and vast majority of adverse events were Grade1/2 and no patients discontinued study treatment due to an adverse event.

In conclusion, this preliminary Phase 2 results are highly encouraging and suggested that GRANITE immunotherapy demonstrated positive early PFS and long-term ctDNA responses, compared with Fluoropyrimidine/Bevacizumab alone, in front-line metastatic MSS-Colorectal cancer, providing the rationale for a confirmatory Phase 3 trial.

A randomized phase 2 study of an individualized neoantigen-targeting immunotherapy in patients with newly diagnosed metastatic microsatellite stable colorectal cancer (MSS-CRC). Hecht JR, Spira AI, Nguyen AV, et al. J Clin Oncol 43, 2025 (suppl 4; abstr LBA13). DOI 10.1200/JCO.2025.43.4_suppl.LBA13

Late Breaking Abstract – 2025 ASCO GI Symposium: Aspirin Reduces Recurrence in Colorectal Cancer Patients with PI3K Pathway Alterations

RR

SUMMARY: ColoRectal Cancer (CRC) is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 154,270 new cases of CRC will be diagnosed in the United States in 2025 and about 52,900 patients will die of the disease. The lifetime risk of developing CRC is about 1 in 23. Among patients with Stage II-III CRC, 20-40% will develop metastatic disease.

The majority of CRC cases (about 75 %) are sporadic whereas the remaining 25 % of the patients have a family history of the disease. Only 5-6 % of patients with CRC with a family history background are due to inherited mutations in major CRC genes, while the rest are the result of accumulation of both genetic mutations and epigenetic modifications of several genes. Colorectal Cancer is a heterogeneous disease classified by its genetics, and even though the diagnosis of Colorectal Cancer in the US is dropping among people 65 years and older, the incidence has been rising in the younger age groups, with 12% of Colorectal Cancer cases diagnosed in people under age 50.

Aspirin (AcetylSalicylic Acid) has been studied as a chemopreventive agent for several decades and the temporal relationship between systemic inflammation and cancer has been a topic of ongoing investigation. The US Preventive Services Task Force (USPSTF) found adequate evidence that Aspirin use reduces the incidence of CRC in adults after 5-10 years of use, and recommends initiating low-dose Aspirin use for the primary prevention of CardioVascular Disease (CVD) and CRC, in adults aged 50-69 years, who have a 10% or greater 10-year CVD risk, are not at increased risk for bleeding, have a life expectancy of at least 10 years, and are willing to take low-dose Aspirin daily for at least 10 years.

Aspirin has been shown to lower the incidence of adenomas and CRC in high-risk patients. Additionally, observational studies suggest that treatment with Aspirin following diagnosis improves Disease-Free Survival (DFS) in unselected populations. Furthermore, retrospective findings indicate that somatic PIK3CA mutations predict treatment response to Aspirin. However this has not been validated in randomized trials.

The ALASCCA trial was designed to find the impact of Aspirin, on the recurrence of CRC with PI3K pathway mutations. The ALASCCA trial is a randomized, double-blind, multicenter, placebo-controlled trial conducted across 33 hospitals in Sweden, Denmark, Finland, and Norway. Researchers screened 3,508 patients diagnosed with Stage II or III colon cancer or Stage I, II, or III rectal cancer and identified 1,103 individuals with PI3K pathway mutations. Participants were categorized into two groups:

• Group A (N=515): Patients with a PIK3CA mutation in exon 9 and/or 20.
• Group B (N=588): Patients with other PI3K mutations, including PIK3CA mutations outside exon 9/20 or mutations in PIK3R1 or PTEN genes.

Of the 626 patients (419 with colon cancer and 207 with rectal cancer) who continued participation in this trial, 157 and 156 patients in Groups A and B respectively, received Aspirin 160 mg daily for 3 years, whereas 157 and 156 patients in each respective group received placebo. The median age was 66 years, 52% of patients were female, and majority of patients were white. Fifty percent of patients with both rectal and colon cancer had received neoadjuvant therapy. The Primary end point was Time to CRC recurrence (TTR). Secondary end points included Disease Free Survival (DFS) in Group A, TTR in Group B, DFS in Group B, and Safety.

The study met its Primary end point and demonstrated that Aspirin use significantly reduced the risk of CRC recurrence. After 3 years of follow up in Group A, patients taking Aspirin had a 51% lower recurrence risk compared to the placebo group (HR=0.49; P=0.044). In Group B, patients taking Aspirin experienced a 58% reduction in recurrence risk versus the placebo group (HR=0.42; P=0.013). Overall, across all groups, Aspirin was associated with a 55% reduced risk of recurrence compared to placebo. There was no statistically significant difference in 3-year DFS rates among those who received Aspirin versus placebo in Group A (88.5% versus 81.4%, respectively; HR=0.61; P =0.091). There was however significantly improved DFS rates in Group B with Aspirin use (89.1% versus 78.7%, respectively; HR=0.51; P=0.17). Severe side effects of daily Aspirin use were rare.

The researchers concluded that this landmark study provides compelling evidence for the role of low-dose Aspirin in reducing colorectal cancer recurrence in patients with PI3K pathway mutations. By integrating precision medicine with a widely available drug, the ALASCCA trial sets the stage for a new standard in colorectal cancer management.

Low-dose aspirin to reduce recurrence rate in colorectal cancer patients with PI3K pathway alterations: 3-year results from a randomized placebo-controlled trial. Martling A, Lindberg J, Myrberg IH, et al. J Clin Oncol. 2025;43(4):LBA125.

Revolutionizing Treatment: Newer Agents and Innovations mCRC Management

RR

Written by: Dr. Jerome Goldschmidt Jr, MD
Sponsored by Takeda

The treatment landscape for metastatic colorectal cancer (mCRC) has seen considerable evolution over the past two decades. Early therapeutic strategies focused on a handful of chemotherapy agents, with incremental progress in survival seen through the addition of targeted therapies like VEGF and EGFR inhibitors. However, while these agents offered modest improvements, they also brought additional toxicity. More recent advancements, particularly in molecular diagnostics, have ushered in a new era of precision medicine, enabling a better understanding of genetic mutations and the tailoring of treatments. This article examines the key advancements in mCRC management, including immunotherapies, targeted therapies, and chemotherapy agents, and how these innovations are transforming the treatment landscape for this complex disease.

For almost two decades mCRC management has revolved around the use of a handful of drugs: 5-fluorouracil (5-FU), leucovorin, oxaliplatin and irinotecan. Additions to the chemotherapy backbones of FOLFOX and FOLFIRI with the VEGF and EGF receptor inhibitors were the first big innovation in the early 2000s. In retrospect, the benefit of adding these targeted agents to the chemotherapy backbone added on average 2-3 months to overall survival with additional toxicity. It took another few years to discover that EGFR blockers were only effective in ~40% of patients with the discovery of mutated KRAS, BRAF and NRAS. To date, biomarkers pointing to the benefit from VEGF inhibition have proven elusive.

This brings us to newer agents which are now interwoven into the tapestry of more modern molecular diagnostics. Molecular diagnostics have changed some of the paradigms in which mCRC patients are treated currently. These agents can be summarized as follows:

Immunotherapies:
Approximately 15% of CRC patients will be classified as having unstable microsatellites. What this means in practical terms are the addition of repeating, multiple CpG islands in the genome of the malignant colonocytes due to inappropriate mismatch repair mechanisms. A little under half of these MSI high patients will have germline mutations in mismatch repair genes like MLH1, MSH2, MSH6 or PMS2 and often present at an earlier age with CRC as part of the “Lynch Syndrome.” More than half of MSI patients will have acquired this genotype through an apparent random methylation of one of these genes which is more common in cells as they senesce. POLE and POLD1 mutations are another family of mutations involving DNA repair that are implicated in the formation of colorectal cancers. These tumors usually have high tumor mutational burden yet are microsatellite stable. The mismatch repair deficient or MSI high colon cancers as well as the POLE and POLD1 mutants are exquisitely sensitive to immune checkpoint inhibitors.1 First line therapies with single agent pembrolizumab and combination ipilimumab/nivolumab are now standard of care.

Targeted therapies:
HER2 directed therapy has long been employed in the more proximal GI tract. HER2 overexpression has been seen in fewer colorectal cancers. Patients will derive benefit with a trastuzumab backbone and the addition of either pertuzumab, tucatinib or lapatinib. The ADC fam-trastuzumab deruxetecan may be employed upon progression.2

The BRAF inhibitor encorafenib and others have long been a staple in the management of melanoma. In CRC, encorafenib is paired with either of the EGFR blockers, panitumumab or cetuximab to extend the usefulness of these antibodies in what would otherwise be a resistant tumor to EGFR blockade.

KRAS G12C is the most commonly mutated form of the KRAS family and has been found to be safely inhibited with two newer agents, sotorasib and adagrasib. Analogous to encorafenib, they must be paired with one of the EGFR blockers approved in mCRC to overcome resistance to these antibodies.

Chemotherapy:
Trifluridine and tipiracil combination by itself or paired with bevacizumab is approved for third line therapy. Modest improvements in overall survival have been seen. It appears to be agnostic in its mechanism of action as it targets DNA synthesis much like its relatives 5FU and capecitabine. Neutropenia appears to be its dose limiting toxicity.

VEGF inhibitors:
Fruquintinib is a novel oral small-molecule tyrosine kinase inhibitor that selectively targets vascular endothelial growth factor receptors (VEGFR-1, -2, and -3). Its mechanism of action involves the inhibition of VEGF-induced phosphorylation of these receptors, which leads to reduced endothelial cell proliferation, migration, and survival, ultimately inhibiting tumor angiogenesis, and promoting tumor cell death. Approved by the FDA on November 8, 2023 for use in adult patients with refractory metastatic colorectal cancer (mCRC), fruquintinib is indicated for those who have previously undergone treatment with fluoropyrimidine-, oxaliplatin-, and irinotecan-based chemotherapy, as well as anti-VEGF and anti-EGFR therapies if RAS wild-type.3

Clinical trials, including FRESCO and FRESCO-2, demonstrated significant improvements in overall survival rates; patients receiving fruquintinib had a median overall survival of 7.4 months compared to 4.8 months for placebo recipients in the FRESCO-2 trial.4 The recommended dosage is 5 mg orally once daily for the first 21 days of each 28-day cycle until disease progression or unacceptable toxicity occurs.5 Common adverse effects include hypertension, palmar-plantar erythrodysesthesia, and proteinuria. This drug represents a critical advancement in the therapeutic landscape for mCRC, particularly in patients who have exhausted other treatment options.

Regorafenib has stood alone for many years as the sole agent in this space. Inhibiting VEGF is the main mechanism of action of this TKI with regards to suppressing colon tumors. It is often used as third line and beyond with only modest benefit. Noteworthy are its significant toxicities at full dose and often requires a ramp up phase to achieve tolerance of the dreaded hand foot syndrome associated with it.

The management of mCRC has made substantial advancements with the introduction of molecular diagnostics and targeted therapies. While the combination of chemotherapy agents and targeted therapies initially provided incremental survival benefits, newer innovations, such as immunotherapies and precision-targeted treatments, are offering more personalized and effective options for patients. However, challenges remain in determining the optimal use of these therapies, managing associated toxicities, and identifying the right biomarkers for treatment selection. As research continues to evolve, the future of mCRC treatment looks increasingly promising, with the potential for even greater advancements in patient outcomes.

Information regarding the studies:
FRESCO – https://jamanetwork.com/journals/jama/fullarticle/2685988
FRESCO2 – https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(23)00772-9/abstract

References

  1. Ambrosini M, et al. Immune checkpoint inhibitors for POLE or POLD1 proofreading-deficient metastatic colorectal cancer. Ann Oncol. 2023;35(7):643-655.
  2. Strickler JH, Cercek A, Siena S, André T, Ng K, Van Cutsem E, et al. Tucatinib plus trastuzumab for chemotherapy-refractory, HER2-positive, RAS wild-type unresectable or metastatic colorectal cancer (MOUNTAINEER): a multicentre, open-label, phase 2 study. Lancet Oncol. 2023;24(5):496-508
  3. S. Food and Drug Administration. FDA approves fruquintinib for metastatic colorectal cancer. FDA website. Published November 8, 2023. Accessed January 31, 2025.
  4. Xu RH, Muro K, Morita S, et al. FRESCO-2: A Phase III trial of fruquintinib in patients with refractory metastatic colorectal cancer. Ann Oncol. 2023;34(6):779-787.
  5. Abernero J, et al. Fruquintinib: An oral inhibitor of VEGFR for the treatment of metastatic colorectal cancer. Clin Cancer Res. 2023;29(4):1025-1033.

Late Breaking Abstract – 2025 ASCO GI Symposium: OPDIVO® Plus YERVOY® Superior to OPDIVO® Alone in MSI-H/MMR Deficient Metastatic Colorectal Cancer

RR

SUMMARY: ColoRectal Cancer (CRC) is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 154,270 new cases of CRC will be diagnosed in the United States in 2025 and about 52,900 patients will die of the disease. The lifetime risk of developing CRC is about 1 in 23.

The majority of CRC cases (about 75 %) are sporadic whereas the remaining 25 % of the patients have a family history of the disease. Only 5-6 % of patients with CRC with a family history background are due to inherited mutations in major CRC genes, while the rest are the result of accumulation of both genetic mutations and epigenetic modifications of several genes. Colorectal Cancer is a heterogeneous disease classified by its genetics, and even though the diagnosis of Colorectal Cancer in the US is dropping among people 65 years and older, the incidence has been rising in the younger age groups, with 12% of Colorectal Cancer cases diagnosed in people under age 50.

The DNA MisMatchRepair (MMR) system is responsible for molecular surveillance and works as an editing tool that identifies errors within the microsatellite regions of DNA and removes them. Defective MMR system leads to MSI (Micro Satellite Instability) and hypermutation, with the expression of tumor-specific neoantigens at the surface of cancer cells, triggering an enhanced antitumor immune response. MSI is therefore a hallmark of defective/deficient DNA MisMatchRepair (dMMR) system and occurs in 15% of all colorectal cancers. Defective MMR can be a sporadic or heritable event. Approximately 65% of the MSI high colon tumors are sporadic and when sporadic, the DNA MMR gene is MLH1. Defective MMR can manifest as a germline mutation occurring in MMR genes including MLH1, MSH2, MSH6 and PMS2. This produces Lynch Syndrome often called Hereditary Nonpolyposis Colorectal Carcinoma – HNPCC, an Autosomal Dominant disorder that is often associated with a high risk for Colorectal and Endometrial carcinoma, as well as several other malignancies including Ovary, Stomach, Small bowel, Hepatobiliary tract, Brain and Skin. MSI is a hallmark of Lynch Syndrome-associated cancers. MSI high tumors tend to have better outcomes and this has been attributed to the abundance of tumor infiltrating lymphocytes in these tumors from increase immunogenicity. These tumors therefore are susceptible to blockade with immune checkpoint inhibitors.

MSI testing is performed using a PCR or NGS based assay and MSI-High refers to instability at 2 or more of the 5 mononucleotide repeat markers and MSI-Low refers to instability at 1 of the 5 markers. Patients are considered Micro Satellite Stable (MSS) if no instability occurs. MSI-L and MSS are grouped together because MSI-L tumors are uncommon and behave similar to MSS tumors. Tumors considered MSI-H have deficiency of one or more of the DNA MMR genes. MMR gene deficiency can be detected by ImmunoHistoChemistry (IHC). NCCN Guidelines recommend MMR or MSI testing for all patients with a history of Colon or Rectal cancer. Unlike Colorectal and Endometrial cancer, where MSI-H/dMMR testing is routinely undertaken, the characterization of Lynch Syndrome across heterogeneous MSI-H/dMMR tumors is unknown.

Nivolumab (OPDIVO®) is a fully human, immunoglobulin G4 monoclonal antibody that binds to the PD-1 receptor and blocks its interaction with PD-L1 and PD-L2, whereas Ipilimumab (YERVOY®) is a fully human immunoglobulin G1 monoclonal antibody that blocks Immune checkpoint protein/receptor CTLA-4 (Cytotoxic T-Lymphocyte Antigen 4, also known as CD152). Blocking the Immune checkpoint proteins unleashes the T cells, resulting in T cell proliferation, activation and a therapeutic response. The FDA in 2018, granted accelerated approval to Ipilimumab for use in combination with Nivolumab, based on CheckMate-142, for the treatment of patients with MSI-H or dMMR metastatic CRC, that has progressed following treatment with a Fluoropyrimidine, Oxaliplatin, and Irinotecan. The FDA in July, 2017, granted accelerated approval to single agent Nivolumab for treatment of this same group of patients.

The CheckMate 8HW is an ongoing Phase III, multinational, open-label, randomized trial evaluating Nivolumab plus Ipilimumab as compared with Nivolumab alone or chemotherapy, in patients with MSI-H or dMMR metastatic CRC. In this study, patients with unresectable or mCRC and MSI-H/dMMR status by local testing who had received 0-1 prior line of therapy were randomly assigned in a 2:2:1 ratio to receive either Nivolumab monotherapy (N=353), Nivolumab plus Ipilimumab combination therapy (N=354), or the investigator’s choice of chemotherapy (mFOLFOX6 or FOLFIRI with or without Bevacizumab or Cetuximab (N=132). Patients who had previously received two or more prior lines of therapy for unresectable or metastatic disease were randomly assigned, in a 1:1 ratio, to receive Nivolumab plus Ipilimumab or Nivolumab alone. In the Nivolumab monotherapy arm, patients received Nivolumab 240 mg IV once every two weeks for six doses, followed by 480 mg IV every four weeks. In the Nivolumab plus Ipilimumab arm, patients were given Nivolumab 240 mg IV plus Ipilimumab 1mg/kg IV every three weeks for four doses, followed by Nivolumab 480 mg IV every four weeks. The median patient age was 64 years and tumor location was in the right colon in two thirds of the patients. Treatments continued until disease progression or unacceptable toxicity in all treatment groups or a maximum of 2 years. The dual Primary end points were Progression-Free Survival (PFS) as determined by Blinded Independent Central Review (BICR) comparing Nivolumab plus Ipilimumab to chemotherapy in the first-line therapy setting, and PFS comparing Nivolumab monotherapy to Nivolumab plus Ipilimumab across all lines of therapy, in patients with centrally confirmed MSI-H/dMMR metastatic CRC. At a median follow-up of 31.5 months the results from the prespecified interim analysis (the primary analysis) showed that the PFS outcomes were significantly better with Nivolumab plus Ipilimumab than with chemotherapy (HR=0.21; P<0.001).

The researchers herein reported the first results from the other dual Primary endpoint of PFS for Nivolumab plus Ipilimumab versus Nivolumab monotherapy across all lines of therapy in patients with centrally confirmed MSI-H/dMMR metastatic CRC. Of all the randomized patients 296 in the Nivolumab plus Ipilimumab group and 286 in the Nivolumab monotherapy group had centrally confirmed MSI-H/dMMR status. With a median follow-up of 47.0 months, Nivolumab plus Ipilimumab demonstrated clinically meaningful and statistically significant improvement in PFS by BICR versus Nivolumab monotherapy, with a median PFS Not Reached (NR) in the Nivolumab plus Ipilimumab group, compared to 39.3 months for those on Nivolumab monotherapy (HR=0.62; P= 0.0003). The PFS rates at 12, 24, and 36 months were higher in the Nivolumab plus Ipilimumab group at 76%, 71%, 68% versus 63%, 56%, 51% for Nivolumab monotherapy.

The Objective Response Rate (ORR) was significantly higher with Nivolumab plus Ipilimumab at 71%, compared to 58% with Nivolumab alone (P=0.0011). No new safety concerns were identified

It was concluded that the CheckMate 8HW study met its dual Primary endpoints, with Nivolumab plus Ipilimumab demonstrating a statistically significant and clinically meaningful improvement in PFS compared to Nivolumab monotherapy across all lines of therapy in MSI-H/dMMR metastatic CRC. Moreover, Nivolumab plus Ipilimumab was associated with higher ORR, confirming its potential as a new standard of care for patients with MSI-H/dMMR metastatic CRC. The CheckMate 8HW study is a pivotal contribution to the treatment landscape of MSI-H/dMMR metastatic Colorectal cancer, providing compelling evidence for the use of Nivolumab plus Ipilimumab in the first-line and beyond.

First results of nivolumab (NIVO) plus ipilimumab (IPI) vs NIVO monotherapy for microsatellite instability-high/mismatch repair-deficient (MSI-H/dMMR) metastatic colorectal cancer (mCRC) from CheckMate 8HW. Andre T, Elez E, Lenz H-J, et al. J Clin Oncol 43, 2025 (suppl 4; abstr LBA143)

SIGNATERA® ctDNA Assay Can Guide Therapy in Early Stage Colorectal Cancer

RR

SUMMARY: ColoRectal Cancer (CRC) is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 154,270 new cases of CRC will be diagnosed in the United States in 2025 and about 52,900 patients will die of the disease. The lifetime risk of developing CRC is about 1 in 23.

It is estimated that approximately 30% of patients with Stage II or III CRC and 60-70% of patients after oligometastatic resection experience recurrence. Adjuvant chemotherapy for patients with resected, locally advanced, node-positive (Stage III) colon cancer has been the standard of care since the 1990s. However, not all patients with Stage III disease benefit from adjuvant chemotherapy. In the IDEA trial, the absolute Disease Free Survival benefit of adjuvant chemotherapy for the lowest-risk Stage III group and the highest-risk group was 8% and 20%, respectively, suggesting that a substantial number of patients with low-risk Stage III cancer can safely forgo adjuvant chemotherapy or be considered for treatment de-escalation. Even though 80% of patients with Stage II colon cancer are cured with surgery alone, adjuvant chemotherapy is recommended for patients who have Stage II colon cancer with high-risk clinicopathological features, including tumor penetration of the serosa (T4 disease). However, the benefit of adjuvant chemotherapy for patients with Stage II disease remains unclear, with less than 5% of patients benefiting from adjuvant chemotherapy. There is therefore an unmet need for more precise markers to predict risk of recurrence after surgery for resectable colon cancer, other than clinicopathological risk factors, and thus avoid exposure to unnecessary chemotherapy.

Circulating Tumor DNA (ctDNA) refers to DNA molecules that circulate in the bloodstream after cell apoptosis or necrosis, and can be detected in the cell-free component of peripheral blood samples (Liquid Biopsy) in almost all patients with advanced solid tumors including advanced CRC. ctDNA is a valuable biomarker and is directly evaluated for evidence of Minimal Residual Disease and allows early detection of relapse. Several studies have shown that detectable ctDNA following curative intent surgery for early stage cancers, including those with Stage II colon cancer, is associated with a very high risk of recurrence (more than 80%) without further adjuvant therapy. It has remained unclear whether adjuvant treatment is beneficial for these ctDNA-positive patients who are at high risk for recurrence.

The BESPOKE CRC trial is a multicenter, prospective, observational study, designed to evaluate the role of Natera’s SIGNATERA® assay in informing adjuvant chemotherapy decisions for patients with surgically resected pathologic Stage II and III Colorectal Cancer (CRC). SIGNATERA® test is a personalized, tumor-informed ctDNA (circulating tumor DNA) assay for tracking 16 tumor-specific mutations in the blood for Minimal Residual Disease (MRD) determination and molecular monitoring. This study aimed to assess whether ctDNA could improve the decision-making process for adjuvant chemotherapy, thereby influencing the course of treatment and ultimately, patient outcomes.

This study included 1780 patients who had undergone surgical resection for Stage II or III CRC. These patients were enrolled in the study and were followed for their ctDNA status at various time points after their resection. The first ctDNA sample was taken for MRD 2 to 6 weeks following surgery (MRD time point). Subsequent samples were collected at 2, 4, and 6 months, and then every 3 months up to 24 months after resection. The surveillance ctDNA collection started at 6 months or later from surgical resection. The treating oncologists were provided with the ctDNA results of their patients and were allowed to base treatment decisions on these findings, within the context of standard-of-care guidelines. After exclusions, 1166 patients remained in the final analysis, 694 patients in the adjuvant chemotherapy cohort and 472 patients in the observation cohort. The median age of the study participants was 61.8 years, majority of the patients were male (56.7%), most patients had stage III CRC (55.7%), 59.5% of patients received adjuvant chemotherapy, while 83.9% of the participants did not experience a recurrence during the study period. The Primary endpoint of this study was to evaluate the impact of ctDNA testing on adjuvant treatment decisions, as well as the rates of asymptomatic CRC recurrences. Secondary endpoints included the MRD clearance rate, survival rates of MRD-negative patients, Overall Survival, and Patient-Reported Outcomes. The median follow-up was 23.9 months

ctDNA and Disease-Free Survival (DFS)
The study found that postoperative ctDNA positivity was a strong predictor of inferior Disease-Free Survival (DFS) in patients with both Stage II and III disease. At the MRD time point (first ctDNA sample 2-6 weeks post surgery), 7.54% of patients with Stage II disease (N= 517) tested positive for MRD versus 28.35% of patients with Stage III disease (N= 649). These findings were crucial for determining which patients might be at higher risk of recurrence.

  • Among Stage II patients, those with positive postoperative ctDNA had a significantly lower 2-year DFS rate of 45.9%, compared to 91.8% in ctDNA-negative patients (HR=11.23; P <0.0001).
  • Among Stage III patients, those with positive ctDNA were also associated with poorer DFS, with a 2-year DFS rate of 35.5% versus 87.4% for ctDNA-negative patients (HR=8.33; P <0.0001).

Further analyses showed that positive ctDNA at the first surveillance time point was linked with an inferior DFS (HR=20.63; P <0.0001). Patients who became positive for ctDNA at any time during surveillance had a 26.4-times higher risk of recurrence compared to those who remained ctDNA-negative.

ctDNA Clearance and Treatment Efficacy
One of the most compelling findings of the study was the correlation between ctDNA clearance during and after adjuvant chemotherapy and improved DFS. Patients whose ctDNA was cleared during treatment had significantly better outcomes:

  • Hazard ratio for DFS at 3 months after chemotherapy: 0.43 (P <.0001)
  • Hazard ratio for DFS at 6 months: 0.31 (P <.0001)

These results suggest that ctDNA clearance could be a powerful marker for assessing the effectiveness of adjuvant chemotherapy, reinforcing its potential as a treatment monitoring tool.

Recurrence Detection and Metastasis-Directed Therapy
The ctDNA test demonstrated high sensitivity in detecting disease recurrence, particularly in the liver, which had the highest sensitivity at 96%. It also showed high sensitivities in detecting recurrences in low-shedding sites like the lung (76%) and peritoneum (79%). Bone and abdominal wall recurrences had a sensitivity of 100%, though the small number of such cases limits the ability to draw firm conclusions.

Of the 188 patients who experienced disease recurrence, 86% had a prior positive ctDNA test. Notably, 30% of those patients received metastasis-directed therapy, with 81% of them undergoing surgical intervention. This emphasizes the potential of serial ctDNA monitoring in improving early detection of recurrences and facilitating more effective interventions, including metastasis-directed therapy, which could provide these patients with a chance for a cure.

Impact of Adjuvant Chemotherapy in MRD-Positive vs MRD-Negative Patients
The study also highlighted the differing effects of adjuvant chemotherapy in MRD-positive versus MRD-negative patients. While MRD-negative patients saw no significant difference in DFS regardless of whether they received chemotherapy or observation, MRD-positive patients showed a clear benefit from adjuvant chemotherapy:

  • 2-year DFS rates for MRD-positive patients was 40.3% with chemotherapy versus 24.7% with observation (HR=0.48; P =0.0008).
  • 2-year DFS rates for MRD-negative patients was 89.7% with chemotherapy versus 89.5% with observation (HR=0.93; P =0.03).

These results underscore the potential of using ctDNA as a tool to help personalize treatment strategies, offering chemotherapy to those who are most likely to benefit (MRD-positive patients) and sparing others from unnecessary treatment.

Summary of Key Findings

  • Tumor-informed ctDNA assays had a significant impact on adjuvant treatment decisions, influencing chemotherapy de-escalation in 16.3% of Stage II/III CRC cases.
  • Postoperative ctDNA positivity correlated with inferior DFS, making it a strong prognostic tool for identifying high-risk patients.
  • ctDNA clearance during and after chemotherapy was associated with improved DFS, highlighting its potential to monitor treatment efficacy.
  • ctDNA assays demonstrated high sensitivity in detecting recurrences, particularly in the liver, and influenced the use of metastasis-directed therapy.
  • Adjuvant chemotherapy showed a clear benefit in MRD-positive patients, further solidifying the role of this assay in personalizing treatment strategies for CRC patients.

This trial positions ctDNA as a pivotal tool in managing CRC, not only as a prognostic marker but also as a means to optimize treatment and improve patient outcomes.

Circulating tumor DNA for detection of molecular residual disease (MRD) in patients (pts) with stage II/III colorectal cancer (CRC): final analysis of the BESPOKE CRC sub-cohort. Shah P, Aushev V, Ensor J, et al. J Clin Oncol. 2025;43(suppl 4):15. doi:10.1200/JCO.2025.43.4_suppl.15

FDA Approves LUMAKRAS® with VECTIBIX® for KRAS G12C-mutated Colorectal Cancer

RR

SUMMARY: The FDA on January 16, 2025, approved Sotorasib (LUMAKRAS®) with Panitumumab (VECTIBIX®) for adult patients with KRAS G12C-mutated metastatic ColoRectal Cancer (mCRC), as determined by an FDA-approved test, who have received prior Fluoropyrimidine, Oxaliplatin, and Irinotecan-based chemotherapy. The FDA also approved the therascreen KRAS RGQ PCR Kit (QIAGEN GmbH) as a companion diagnostic device to aid in identifying patients with colorectal cancer whose tumors harbor KRAS G12C mutations and who may be eligible for LUMAKRAS® with VECTIBIX®.

Colorectal Cancer (CRC) is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 154,270 new cases of CRC will be diagnosed in the United States in 2025 and about 52,900 patients will die of the disease. The lifetime risk of developing CRC is about 1 in 23.

Approximately 15-25% of the patients with CRC present with metastatic disease at the time of diagnosis (synchronous metastases) and 50-60% of the patients with CRC will develop metastatic disease during the course of their illness. First line treatment of metastatic CRC includes Oxaliplatin or Irinotecan, in combination with a Fluoropyrimidine and Leucovorin (FOLFOX or FOLFIRI respectively), along with a VEGF targeting agent such as Bevacizumab or EGFR targeting agents such as Cetuximab (ERBITUX®) and Panitumumab. Patients with Stage IV colorectal cancer are now routinely analyzed for extended RAS and BRAF mutations. KRAS mutations are predictive of resistance to EGFR targeted therapy. Patients who progress following these therapies are considered to have refractory disease. These patients sometimes are rechallenged with previously administered chemotherapeutic agents, but often receive Regorafenib (STIVARGA®), an oral multikinase inhibitor with antiangiogenic activity, or LONSURF® (a fixed dose combination of Trifluridine and Tipiracil). These therapies, however, have shown limited efficacy.

The KRAS (Kirsten rat sarcoma viral oncogene homologue) proto-oncogene encodes a protein that is a member of the small GTPase super family. The KRAS gene provides instructions for making the KRAS protein, which is a part of a signaling pathway known as the RAS/MAPK pathway. By relaying signals from outside the cell to the cell nucleus, the protein instructs the cell to grow, divide and differentiate. KRAS gene is in the Ras family of oncogenes, which also includes two other genes, HRAS and NRAS. When mutated, oncogenes have the potential to change normal cells to cancer cells. KRAS is the most frequently mutated oncogene in human cancers and these cancers are often associated with resistance to targeted therapies and poor outcomes. The KRAS G12C mutation occurs in approximately 12-15% of Non Small Cell Lung Cancers (NSCLC) and in 3-5% of colorectal cancers and other solid cancers. G12C is a single point mutation with a Glycine-to-Cysteine substitution at codon 12. This substitution favors the activated state of KRAS, amplifying signaling pathways that lead to oncogenesis.

Sotorasib is a small molecule that specifically and irreversibly inhibits KRAS G12C protein and traps KRAS G12C in the inactive GDP-bound state, thus blocking downstream proliferation and survival signaling. Unlike the efficacy of single-agent KRAS G12C inhibitors in Non Small Cell Lung Cancer with KRAS G12C mutation, KRAS G12C inhibition alone has limited activity in patients with colorectal cancer. This has been attributed to upstream reactivation of the Epidermal Growth Factor Receptor (EGFR) pathway resulting in treatment-induced resistance, following selective inhibition of KRAS G12C. However, dual KRAS G12C and EGFR blockade can overcome treatment resistance in patients with colorectal cancer with KRAS G12C mutation. In the CodeBreaK 101 Phase 1b trial involving patients with chemorefractory colorectal cancer with mutated KRAS G12C, the Response Rate was 30% with Sotorasib plus Panitumumab, as compared with 9.7% with Sotorasib monotherapy.

The present FDA approval was based on CodeBreaK 300 trial, which is an international, multicenter, open-label, randomized, active-controlled Phase III study, conducted to evaluate the efficacy and safety of two different doses of Sotorasib (960 mg and 240 mg) in combination with Panitumumab as compared with the investigator’s choice of standard-care therapy (Trifluridine-Tipiracil or Regorafenib) in patients with chemorefractory metastatic colorectal cancer with KRAS G12C mutation. A lower dose of Sotorasib 240 mg orally once daily was tested in this study because of the nonlinear pharmacokinetic properties of Sotorasib. A total of 160 patients were randomly assigned in a 1:1:1 ratio to receive Sotorasib 960 mg orally once daily plus Panitumumab 6 mg/kg IV every 2 weeks (the 960 mg Sotorasib/Panitumumab group; N=53), Sotorasib 240 mg orally once daily plus Panitumumab (the 240 mg Sotorasib/Panitumumab group; N=53), with each treatment cycle repeating every 28 days, or the investigator’s choice of standard of care therapy which could be either Trifluridine-Tipiracil 35 mg/m2 (up to a maximum of 80 mg per dose) orally twice daily on days 1-5 and days 8-12 every 28 days, or Regorafenib 160 mg orally once daily for the first 21 days of each 28-day cycle (N=54). Treatment continued until disease progression or unacceptable toxicities. The median age was 61 years and majority of patients had more than 2 or more lines of previous anti-cancer therapy. KRAS G12C mutation was confirmed by prospective central molecular testing. Randomization was stratified according to previous use of antiangiogenic therapy, the time from initial diagnosis of metastatic disease to randomization and ECOG-PS. The Primary end point was Progression Free Survival (PFS) as assessed by Blinded Independent Central Review (BICR). Key Secondary end points included Overall Survival (OS) and Objective Response Rate (ORR) and Duration of Response (DOR).

After a median follow up of 7.8 months, both Sotorasib combinations (960 mg and 240 mg) plus Panitumumab demonstrated significantly longer PFS compared to standard of care therapy. The median PFS was 5.6 months and 3.9 months in the 960 mg Sotorasib/Panitumumab and 240 mg Sotorasib/Panitumumab groups, respectively, as compared with 2.2 months in the standard of care group (HR for 960 mg group=0 49; P=0.006) (HR for 240 mg group=0.58; P=0.03). The improvement in PFS was observed across key subgroups, including tumor sideness/primary tumor location, prior lines of therapy, and the presence or absence of liver metastases. The Objective Response Rate was 26.4%, 5.7%, and 0% in the 960 mg Sotorasib/Panitumumab, 240 mg Sotorasib/Panitumumab, and standard of care groups, respectively and the median DOR was 4.4 months in the 960 mg Sotorasib/Panitumumab group. Overall Survival data is immature. While this trial was not powered to compare the two Sotorasib/Panitumumab groups directly, the 960 mg dose appeared to yield more clinically significant benefits than the 240 mg dose, across all efficacy endpoints, without additional toxic effects. The final analysis of PFS for patients randomized to the 240 mg Sotorasib/Panitumumab arm compared to the standard of care groups was not statistically significant.
Grade 3 or higher treatment-related adverse events occurred in 35.8%, 30.2%, and 43.1% of patients, respectively. Skin-related toxic effects and hypomagnesemia were the most common adverse events observed with Sotorasib/Panitumumab.

It was concluded from this study that Sotorasib 960 mg in combination with Panitumumab resulted in significantly longer Progression Free Survival and a higher Objective Response Rate than standard of care treatment. Ongoing analysis and longer follow-up will provide additional insights into Overall Survival outcomes.

Sotorasib plus Panitumumab in Refractory Colorectal Cancer with Mutated KRAS G12C. Fakih MG, Salvatore L, Esaki T, et al. N Engl J Med 2023;389:2125-2139.

FDA Grants Accelerated Approval to BRAFTOVI® with ERBITUX® and mFOLFOX6 for Metastatic CRC with a BRAF V600E Mutation

RR

SUMMARY: The FDA on December 20, 2024, granted accelerated approval to Encorafenib (BRAFTOVI®) in combination with Cetuximab (ERBITUX®) and modified Fluorouracil, Leucovorin, and Oxaliplatin (mFOLFOX6) for patients with metastatic colorectal cancer with a BRAF V600E mutation, as detected by an FDA-approved test (Qiagen therascreen BRAF V600E RGQ polymerase chain reaction kit). ColoRectal Cancer (CRC) is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 152,810 new cases of CRC were diagnosed in the United States in 2024 and about 53,010 patients died of the disease. The lifetime risk of developing CRC is about 1 in 23.

Advanced colon cancer is often incurable and standard chemotherapy when combined with anti EGFR (Epidermal Growth Factor Receptor) targeted monoclonal antibodies such as VECTIBIX® (Panitumumab) and ERBITUX® (Cetuximab) as well as anti VEGF agent AVASTIN® (Bevacizumab), have demonstrated improvement in Progression Free Survival (PFS) and Overall Survival (OS). The benefit with anti EGFR agents however is only demonstrable in patients with metastatic CRC (mCRC) whose tumors do not harbor KRAS mutations in codons 12 and 13 of exon 2 (KRAS Wild Type). It is now also clear that even among the KRAS Wild Type patient group about 15-20% have other rare mutations such as NRAS and BRAF mutations, which confer resistance to anti EGFR agents. Patients with stage IV colorectal cancer are now routinely analyzed for extended RAS and BRAF mutations. KRAS mutations are predictive of resistance to EGFR targeted therapy. Approximately 8-15% of all metastatic CRC tumors present with BRAF V600E mutations, and BRAF V600E is recognized as a marker of poor prognosis in this patient group. These patients tend to have aggressive disease with a higher rate of peritoneal metastasis and do not respond well to standard treatment intervention. Approximately 20% of the BRAF-mutated population in the metastatic setting has MSI-High tumors, but MSI-High status does not confer protection to this patient group.

The Mitogen-Activated Protein Kinase pathway (MAPK pathway) is an important signaling pathway which enables the cell to respond to external stimuli. This pathway plays a dual role, regulating cytokine production and participating in cytokine dependent signaling cascade. The MAPK pathway of interest is the RAS-RAF-MEK-ERK pathway. The RAF family of kinases includes ARAF, BRAF and CRAF signaling molecules. BRAF is a very important intermediary of the RAS-RAF-MEK-ERK pathway. The BRAF V600E mutations results in constitutive activation of the MAP kinase pathway. Inhibiting BRAF can transiently reduce MAP kinase signaling. However, this can result in feedback upregulation of EGFR signaling pathway, which can then reactivate the MAP kinase pathway. This aberrant signaling can be blocked by dual inhibition of both BRAF and EGFR. It should be noted that BRAF V600E-mutated CRC is inherently less sensitive to BRAF inhibition than Malignant Melanoma.

BRAFTOVI® (Encorafenib) is a BRAF inhibitor and has target binding characteristics that differ from other BRAF inhibitors such as ZELBORAF® (Vemurafenib) and TAFINLAR® (Dabrafenib), with a prolonged target dissociation half-life and higher potency. The FDA in 2020, approved Encorafenib in combination with Cetuximab (ERBITUX®) for the treatment of adult patients with metastatic ColoRectal Cancer (mCRC) with a BRAF V600E mutation, detected by an FDA-approved test, after prior therapy, based on the BEACON CRC trial. However, first line treatment options for this group of patients remains an unmet need.

BREAKWATER is an ongoing, active-controlled, open-label, multicenter, randomized, Phase 3 study in which first line Encorafenib plus Cetuximab plus or minus chemotherapy was compared with Standard of Care chemotherapy alone, in patients with BRAF V600E-mutant mCRC. In this trial, patients were initially randomly assigned 1:1:1 to receive either Encorafenib orally once daily with Cetuximab IV infusion every 2 weeks (Encorafenib plus Cetuximab arm), Encorafenib orally once daily with Cetuximab IV infusion every 2 weeks and mFOLFOX6 every 2 weeks (Encorafenib plus Cetuximab plus mFOLFOX6 arm), or control group patients who received mFOLFOX6 (Leucovorin, Fluorouracil and Oxaliplatin) or FOLFOXIRI (Leucovorin, Fluorouracil, Oxaliplatin, and Irinotecan), both every 2 weeks, or Capecitabine plus Oxaliplatin (every 3 weeks), each with or without Bevacizumab . The trial was subsequently amended to limit randomization and compare the Encorafenib plus Cetuximab plus mFOLFOX6 group and the control group. Treatment in both groups continued until disease progression, unacceptable toxicity. The Primary endpoint was Progression Free Survival (PFS) and Objective Response Rate (ORR) and Secondary endpoints included Duration of Response, Overall survival, Time to Response and patient Reported Outcomes.

The present FDA accelerated approval was based on the results of the Encorafenib plus Cetuximab plus mFOLFOX6 group, compared to the control group. The major efficacy outcome measure was confirmed ORR assessed by Blinded Independent Central Review and evaluated in the first 110 patients randomly assigned in each treatment group. The ORR was 61% in the Encorafenib plus Cetuximab plus mFOLFOX6 group compared to 40% in the control group. Median Duration of Response was 13.9 months and 11.1 months in the two groups respectively. PFS and OS data in this ongoing trial are immature. The most common grade 3 or 4 laboratory abnormalities were increased lipase and decreased neutrophil count.

In conclusion, a combination of Encorafenib and Cetuximab plus mFOLFOX6 resulted in a statistically significant and clinically meaningful improvement in Response Rate and Durability of Response in treatment-naïve metastatic CRC patients with a BRAF V600E mutation. Continued approval for this indication is contingent upon verification of clinical benefit.

https://www.fda.gov/drugs/resources-information-approved-drugs/fda-grants-accelerated-approval-encorafenib-cetuximab-and-mfolfox6-metastatic-colorectal-cancer-braf