A new study finds there are a subset of patients who not only don't need the treatment but may be harmed by chemotherapy. The patients have a DNA mismatch that makes chemotherapy a waste of time and possibly dangerous.
Mayo Clinic researchers say surgery alone would be sufficient treatment. About 15 percent of colon cancer patients fall into this subset. And there is a simple test to help determine which patients this applies to.
The research, presented in Chicago at the American Society of Clinical Oncology meeting, confirms previous research.