Immunotherapy could potentially cut death and recurrence rates in half for colon cancer patients.
A fresh take on how immunotherapy is revolutionizing the treatment landscape for colon cancer:
There's no shortage of treatments for colon cancer, but not all of them work for every cancer type. For instance, deficient mismatch repair (dMMR) colon cancer—accounting for around 5-15% of cases—often shows less responsiveness to chemotherapy compared to other types. But here's some heartening news: combining immunotherapy with chemotherapy after surgery for stage 3 colon cancer might just halve the recurrence and death rates for individuals with dMMR colon cancer. Talk about progress!
As of 2020, around the world were diagnosed with colorectal cancer annually, making it the third most common cancer globally. Traditional treatments include surgery, radiation therapy, immunotherapy, and chemotherapy, but the challenge lies in finding an effective regimen for all types of colorectal cancer.
Enter a recent study presented at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting, which suggests that combining immunotherapy with chemo might do the trick for dMMR stage 3 colon cancer. The findings are yet to be published in a peer-reviewed journal, though.
To reach this conclusion, researchers recruited 712 participants aged 64, on average, with dMMR stage 3 colon cancer for a phase III clinical trial. This stage of colorectal cancer means the cancer has spread to the lymph nodes but not elsewhere. Participants had their cancer surgically removed and still had cancer cells in their lymph nodes. They were divided into two groups; one receiving just chemotherapy for colon cancer, and the other taking a combo of mFOLFOX6 (chemotherapy) and an immunotherapy drug called atezolizumab, which specifically targets proteins in cancer cells.
By binding and blocking a protein called PD-L1, atezolizumab helps the immune system detect and attack cancer cells better. When the study concluded, participants who received chemotherapy plus immunotherapy experienced a 50% decrease in cancer recurrence and death—known as disease-free survival (DFS)—compared to those who got chemotherapy alone.
Frank Sinicrope, MD, the lead author of the study and an oncologist at the Mayo Clinic, expressed his excitement about the results, commenting, "This study represents a major advance in the adjuvant treatment of dMMR stage 3 colon cancer and will change the treatment for this type of cancer."
Though the current findings are promising, researchers are calling for further studies to gather long-term data on survival and recurrence. Additionally, biomarker analyses and quality-of-life assessments will be critical in determining which patients benefit the most from this combined treatment approach.
Top surgeons, like Glenn S. Parker, MD, FACS, FASCRS, also applauded the results of the study. He said, "The use of atezolizumab, an immune checkpoint inhibitor, alongside standard chemotherapy in stage III dMMR colon cancer represents a significant step forward in the care of our patients."
The future of colon cancer treatment looks bright with this newly established treatment approach, leading to more personalized and effective care for patients. Get ready to see your oncologist's toolkit expand beyond regular chemo and radiation—imunotherapy is here to stay!
- The ongoing revolution in the treatment landscape for colorectal cancer is particularly significant for dMMR colon cancer, as combining immunotherapy with chemotherapy post-surgery for stage 3 cases has been shown to potentially cut recurrence and death rates in half.
- Around the world are diagnosed with colorectal cancer annually, and while traditional treatments like surgery, radiation therapy, immunotherapy, and chemotherapy exist, finding an effective treatment regimen for all types of colorectal cancer remains a challenge.
- In a recent study presented at the 2025 ASCO Annual Meeting, the combination of immunotherapy and chemo showed promise for dMMR stage 3 colon cancer, though the findings are yet to be published in a peer-reviewed journal.
- In this study, researchers recruited 712 participants with dMMR stage 3 colon cancer for a phase III clinical trial, where they found that participants who received chemotherapy plus immunotherapy experienced a 50% decrease in cancer recurrence and death compared to those who got chemotherapy alone.
- The future of colon cancer treatment appears bright with this newly established treatment approach, as it promises more personalized and effective care, with oncologists likely to further expand their toolkit beyond regular chemo and radiation to include immunotherapy.
