Oncology is a specialized field of medicine dedicated to the diagnosis and treatment of cancer. An oncologist is a highly trained physician who manages a patient’s care journey from initial diagnosis through treatment. Tracking the number of these specialists practicing in the United States is important for public health planning. Workforce data helps determine the capacity of the healthcare system to meet the rising demand for cancer care, which is driven by population growth and an aging demographic. Ensuring an adequate supply of oncologists is necessary to maintain equitable access to specialized cancer treatment.
The National Count of Practicing Oncologists
Determining the precise number of oncologists is complicated by the diverse nature of the specialty. The American Society of Clinical Oncology (ASCO) reported that in 2023, approximately 15,959 medical and hematology oncologists were engaged in patient care across the U.S. However, comprehensive datasets including all subspecialties suggest the total number of physicians who identify as oncologists or in related subspecialties is over 28,000.
The overall density of the workforce relative to the population is a growing concern. For example, the density of medical and hematology oncologists for the population aged 55 and older declined to 14.9 per 100,000 people in 2024, down from 15.9 per 100,000 a decade earlier. This downward trend highlights the increasing pressure on the existing oncology workforce to manage a rising patient load.
Defining Key Oncological Subspecialties
The total number of oncologists is composed of several distinct subspecialties, each focusing on a different treatment modality. The three primary types are Medical, Radiation, and Surgical Oncology, and their collaboration is central to a comprehensive treatment plan.
Medical Oncologists manage systemic treatments, which involve drug-based therapies that travel throughout the body. These specialists utilize treatments such as chemotherapy, targeted therapy, and immunotherapy.
Radiation Oncologists use high-energy radiation, such as X-rays or proton beams, to precisely target and destroy cancer cells within a specific area of the body. This technique is often used to shrink tumors before surgery or eliminate residual cancer cells afterward.
Surgical Oncologists specialize in the diagnosis and removal of cancerous tumors and surrounding tissues. Their work involves performing biopsies, staging the cancer, and physically removing the malignant tissue.
Geographic Distribution and Workforce Density
Despite the national count, the distribution of oncologists across the U.S. is highly uneven, creating significant disparities in access to care. Oncologists are heavily concentrated in major metropolitan areas, meaning 64% of U.S. counties had no practicing oncologist with a primary office location in 2019.
The disparity is stark when comparing physician-to-patient ratios: urban areas report a density of about 16.6 per 100,000 people, while rural areas have a significantly lower density of 6.5 per 100,000 people. These underserved areas, often called “oncology deserts,” force patients to travel long distances for treatment, potentially delaying care. Projections suggest that by 2037, non-metropolitan areas may only meet 29% of their demand for medical and hematology oncologists, while metropolitan areas will meet their full demand.