A new immunotherapy-only approach is offering real hope to people with early-stage cancers that have a specific genetic mutation called mismatch repair-deficiency (MMRd). In a large clinical trial, nearly 80% of patients with rectal, colon, stomach, esophageal, and other MMRd cancers were successfully treated using immunotherapy alone — with no need for surgery, chemotherapy, or radiation. For rectal cancer patients, the response rate was 100%. This treatment uses a type of immunotherapy called a checkpoint inhibitor, which helps the immune system recognize and destroy cancer cells. It’s a major shift in care, especially for cancers that typically require organ removal or harsh treatments.
Why does this matter? For many patients, standard treatments like surgery and radiation can lead to permanent changes in bowel, urinary, or sexual function — or even infertility. This new strategy preserves quality of life and may especially help those with Lynch syndrome, a condition that increases cancer risk but often responds poorly to chemotherapy. Importantly, the FDA has granted breakthrough status to the immunotherapy drug used, Jemperli (dostarlimab), based on these promising results. As research continues, doctors hope to extend this approach to more cancer types, beyond those with MMRd. (Source: Memorial Sloan Kettering)
