Cancer Research

9-Week Immunotherapy Before Surgery Keeps Colon Cancer Patients Relapse-Free for 3 Years

A UK clinical trial found that nine weeks of immunotherapy before surgery produced remarkable results in a specific type of colorectal cancer. In the NEOPRISM-CRC study, patients with MMR-deficient colorectal cancer received pembrolizumab prior to surgery instead of the standard post-surgery chemotherapy. After 33 months of follow-up, not a single patient had experienced a cancer recurrence. This compares favorably to standard care, where roughly 25% of similar patients relapse within three years. Researchers also developed personalized blood tests to detect residual cancer DNA, potentially allowing doctors to tailor treatment intensity based on individual response. The findings suggest flipping the treatment order — immunotherapy first, surgery second — could offer significantly stronger and more durable protection for eligible patients.