Bowel Cancer Trial Sees Zero Relapses After 33 Months

Thirty-two bowel cancer patients just hit a milestone that seemed impossible a few years ago. After receiving a new immunotherapy treatment before surgery, not one of them has seen their cancer return in 33 months.

The NEOPRISM-CRC trial, led by University College London, flipped the traditional treatment script. Instead of surgery followed by months of grueling chemotherapy, patients received short courses of pembrolizumab, an immunotherapy drug, for up to nine weeks before their operations.

The results speak for themselves. Normally, about 25% of patients who get standard treatment relapse within three years. This trial? Zero relapses.

"Seeing that no patients have experienced a cancer recurrence after almost three years of follow-up is extremely encouraging," said Dr. Kai-Keen Shiu, the trial's chief investigator. The treatment worked even for patients who still had small amounts of cancer remaining after surgery, which neither grew nor spread during follow-up.

The trial focused on patients with a specific genetic profile found in 10% to 15% of bowel cancer cases. These MMR deficient tumors historically respond poorly to standard treatments and are more likely to return.

What makes this even more exciting is the personalized blood test researchers developed alongside the treatment. These tests can predict early whether the immunotherapy is working and whether any cancer cells remain in the bloodstream, allowing doctors to customize care for each patient.

Christopher Burston, 73, was one of the trial participants. Three years after treatment, he's back to his normal life with regular checkups. "I feel very lucky that I've reached the stage where my main problem is age rather than cancer or any illness," he said.

The Ripple Effect

This breakthrough comes at a critical time. Bowel cancer is now the number one cause of cancer-related death in adults under 50 in the United States. It's the third most common cancer diagnosis overall and the second leading cause of cancer-related death for both men and women.

The disease affects about 44,000 people yearly in the UK alone. While early detection offers excellent outcomes (90% of stage 1 patients survive five years or more), survival rates plummet as the cancer advances. Stage 3 survival drops to 65%, and stage 4 to just 10%.

This trial suggests a future where fewer patients reach those advanced stages. By using immunotherapy to eliminate cancer more completely before it can spread, doctors might prevent the disease from ever coming back.

The research team will present their full findings at the American Association for Cancer Research Annual Meeting in April 2026. If these results hold and expand to larger trials, this approach could become the new standard of care for thousands of patients every year.