Immunotherapy has saved countless lives but it is not effective for all cancer patients and predicting who should be using this therapy has been difficult. New results from Luc G. Morris, MD (Damon Runyon Clinical Investigator '14-'17) at Memorial Sloan Kettering Cancer Center, New York, and colleagues, now shed light on this dilemma. Tumors with a large number of DNA mutations are more likely to respond to immunotherapies than are cancers with fewer mutations and result in longer survival for people who receive treatment. The data also showed that the number of mutations that predicted a good response to immunotherapy varied from one type of cancer to another: as few as six mutated genes per million DNA bases in a breast cancer, but colorectal cancer needed 52 to be vulnerable. This means that researchers will need to set a mutation threshold for each cancer type. This new information may help guide doctors in selecting the patients who are most likely to respond to immunotherapies and to spare others from the treatments' side effects, which can include kidney failure and lung problems.
This research was published in Nature Genetics.
