A clinical drug trial recently provided some groundbreaking results at Memorial Sloan Kettering Cancer Center in New York for people with mismatch repair-deficient rectal cancer.

The findings of a small clinical trial with 14 patients were presented at the American Society of Clinical Oncology annual meeting in June 2022 by researchers from MSK. In six months of treatment with dostarlimab, a monoclonal antibody therapy drug, all 14 patients saw their colorectal cancer tumors vanish entirely.

In the study, all 14 patients received the immunotherapy treatment dostarlimab as the first-line treatment for mismatch repair-deficient locally advanced rectal cancer. MSK researchers administered single-agent dostarlimab, an anti-PD-1 monoclonal antibody, every three weeks for six months in patients with mismatch repair-deficient stage 2 and 3 rectal adenocarcinomas, to be followed by standard chemoradiation and surgery.

All 14 patients who initiated treatment and had at least six months of follow-up saw no evidence of a tumor through numerous tests including an MRI, PET scan, and biopsy to name a few. Because of the disappearance of the tumors, none of the patients required chemoradiation or surgery.

While mismatch repair-deficient colon cancer is not the most common type of colon cancer (only about 3-5% of colon cancers), the findings showed astounding results of what appears to be an actual cure for this type of cancer without surgery or chemotherapy. 5 years of follow-up monitoring will be required to confirm this result, so there is still a long way to go.

Links:

• https://www.manisteenews.com/news/article/Small-study-miraculous-results-All-14-patients-17225373.php
• https://www.nejm.org/doi/full/10.1056/NEJMoa2201445