Immunotherapy-First Bowel Cancer Trial Reports Zero Relapses After 33 Months

A UK-led NEOPRISM-CRC trial treated 32 patients with stage 2/3 bowel cancer using up to 9 weeks of pembrolizumab before surgery instead of post‑op chemotherapy. About 59% had no detectable cancer after treatment and surgery; after 33 months, none had a cancer relapse. The researchers highlight the potential for durable disease control with preoperative immunotherapy and are developing blood tests and immune profiling to predict responders, noting that roughly 25% relapse is expected with standard treatment after three years.