Adding Immunotherapy to Chemoradiotherapy in Rectal Cancer Shows Safety, No Efficacy Gain

The combination therapy of Yervoy (ipilimumab), an anti–CTLA-4 therapy, and Opdivo (nivolumab), an anti–PD-1 therapy, is safe and feasible, demonstrating no statistically significant increase in surgical complications or reoperation rates compared to chemoradiotherapy (CRT) alone according to phase 2 results from the Chinorec trial published in JAMA Network Open . The trial data was an important step in exploring immunotherapy for microsatellite-stable (MSS) rectal cancer, a group historically resistant to immune checkpoint inhibitors (ICIs).

ICIs have revolutionized treatment for several cancers, but their benefits in colorectal cancer have largely been confined to the 10–15% of patients with microsatellite instability (MSI). For the majority with MSS disease, ICIs alone have shown l