[Skip to Content]
Find care at Nemours Children's HealthDoctorsLocations

Health Care Providers: Oncologists

  • Listen
      mp3

What Is Oncology?

Oncology (ahn-KOL-eh-jee) is the medical specialty focused on the study, diagnosis, and treatment of cancer.

What Is an Oncologist?

An oncologist (ahn-KOL-eh-jist) is a doctor who diagnoses and treats different types of cancer.

Why Would Someone Need One?

Oncologists diagnose and treat cancer. They:

  • find out what stage a person's cancer is in (how much cancer is in the body and where it is)
  • prescribe cancer treatment, such as medicines, chemotherapy, radiation therapy, stem cell transplants, and surgery
  • give ongoing care for patients during and after cancer treatment

They do such medical tests and procedures as:

  • biopsies
  • bone marrow aspiration and biopsy
  • bone scan (used to find cancer or see how well treatment is working)
  • blood cell count tests
  • tumor marker tests (to look for substances made by cells in response to cancer)

What Is Their Training?

An oncologist's training typically includes:

  • 4 years of pre-medical education at a college or university
  • 4 years of medical school — a medical degree (MD) or doctor of osteopathic medicine (DO) degree
  • 3 years of residency (professional training in a hospital or clinic) in internal medicine
  • 2 years of fellowship in medical oncology. A “fellow” is a doctor who had more specialty training after completing medical school and a residency.

They can also do special training in a subspecialty area; for example, pediatric oncology and hematology-oncology (treatment of cancers and blood disorders).

Good to Know

Surgical oncologists first become general surgeons in a 5-year residency and then complete a fellowship in oncology and the removal of tumors.

Date reviewed: September 2022