The term "Comprehensive Cancer Center" can be attached to any oncology practice but it is better used to describe levels of certification by one of two bodies, The National Comprehensive Cancer Network or the National Cancer Institute.

The National Comprehensive Cancer Network� (NCCN�), a not-for-profit alliance of 25 of the world's leading cancer centers devoted to patient care, research, and education, is dedicated to improving the quality, effectiveness, and efficiency of cancer care so that patients can live better lives. Through the leadership and expertise of clinical professionals at NCCN Member Institutions, NCCN develops resources that present valuable information to the numerous stakeholders in the health care delivery system. As the arbiter of high-quality cancer care, NCCN promotes the importance of continuous quality improvement and recognizes the significance of creating clinical practice guidelines appropriate for use by patients, clinicians, and other health care decision-makers.

NCI-designated cancer centers are institutions dedicated to research in the development of more effective approaches to prevention, diagnosis, and treatment of cancer. There are three types: Cancer Centers, Comprehensive Cancer Centers, and Basic Laboratory Centers. Cancer Centers must demonstrate scientific leadership, resources, and capabilities in some combination of laboratory, clinical, or population science. Comprehensive Cancer Centers must demonstrate reasonable depth and breadth of research in each of three major areas: laboratory, clinical, and population-based research, as well as substantial transdisciplinary research that bridges these scientific areas. Basic Laboratory Cancer Centers conduct only laboratory research and do not provide patient treatment. There is a total of 68 NCI-designated Cancer centers; 20 Cancer Centers, 41 Comprehensive Cancer Centers, and 7 Basic Laboratory Cancer Centers.