Khaberni - A new clinical trial has shown that administering immunotherapy before surgery can significantly improve treatment outcomes for patients with colon and rectal cancer.
Patients who received a short course of immunotherapy instead of chemotherapy after surgery remained cancer-free for almost three years.
The trial, named NEOPRISM-CRC, was conducted by researchers at University College London and University College London Hospitals, involving 32 patients with stage II or III colorectal cancer, who had a specific genetic pattern representing about 10 to 15% of cases.
The participants received the drug "pembrolizumab" for nine weeks before surgery, instead of the traditional approach based on surgery followed by several months of chemotherapy.
Early results showed that 59% of the patients had no detectable cancer after completing immunotherapy and undergoing surgery. Now, after 33 months of follow-up, none of the patients have experienced a relapse, including those whose tumors completely disappeared and those who still have small remnants of cancer, as none of the remaining cancer grew or spread over time.
This outcome contrasts with standard care, where cancer recurrence is expected within three years for about 25% of patients treated with surgery followed by chemotherapy.
The researchers also developed personalized blood tests that can detect whether cancer DNA is still present in the bloodstream, which may allow doctors to determine if the treatment has been successful early.
Dr. Kai Kin Shiou, the leading researcher of the trial, said, "Seeing that no patient has suffered a relapse after three years is very encouraging. What's exciting is that we may now be able to predict who will respond to treatment using personalized blood tests and immune profiling."
He added that these tools could help tailor treatment, identifying patients who respond well and may need less treatment, versus those more likely to relapse who would need additional treatment.
The researchers found that the disappearance of tumor DNA from the blood closely correlates with patients remaining cancer-free long-term. They also discovered that immune profiling of tumor tissues, before starting treatment, could help predict the response.
Among the inspiring cases, Christopher Burnston (73 years old) was diagnosed with stage III cancer in February 2023. After receiving three doses of immunotherapy over nine weeks followed by surgery in May 2023, doctors said "the cancer had melted." Nearly three years later, Christopher remains cancer-free and has returned to his normal life.
The full results of the study were presented at the annual meeting of the American Association for Cancer Research in 2026 in San Diego.
