National Cancer InstituteThe National Cancer Institute (NCI) is the Federal Government's principal agency for cancer research and training and is part of the National Institutes of Health (NIH). The NCI coordinates the National Cancer Program, which conducts and supports research, training, health information dissemination, and other programs with respect to the cause, diagnosis, prevention, and treatment of cancer, rehabilitation from cancer, and the continuing care of cancer patients and the families of cancer patients.