An oncologist is a healthcare provider who specializes in diagnosing and treating cancer. They’ll diagnose your cancer and identify treatment options. They’ll discuss each option’s benefits and side effects. They also oversee your treatment and manage your post-treatment care.


What is an oncologist?

An oncologist is a healthcare provider who specializes in diagnosing and treating cancer. Oncologists manage your cancer treatment throughout your illness. They’ll:

  • Help diagnose your cancer.
  • Identify treatment options and discuss each option’s benefits and side effects.
  • Oversee your treatment.
  • Manage your post-treatment care.


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Are there different types of oncologists?

Cancer is a multifaceted illness, which is why there are several different types of oncologists. Some oncologists specialize in certain treatments. Other oncologists specialize in certain kinds of cancer. Here are some examples of the different types of oncologists:

  • Surgical oncologists. If your biopsy shows cancer cells, this is the healthcare provider who does the surgery to remove cancer that hasn’t spread. They remove your tumor and surrounding tissues. They help you prepare for and recover from your surgery.
  • Medical oncologists. These healthcare providers treat cancer using chemotherapy, hormonal therapies, immunotherapy and other targeted treatments. People often think of the medical oncologist as their primary cancer doctor. Most medical oncologists also specialize in hematology.
  • Radiation oncologists. These healthcare providers use radiation therapy that’s tailored to your specific cancer.
  • Gynecologic oncologists. These oncologists treat gynecologic cancer such as cervical cancer, cancer of the uterus and ovarian cancer.
  • Pediatric oncologists. These oncologists treat cancers that are more common in children than in adults, such as childhood acute lymphoblastic leukemia, Ewing sarcoma and childhood brain tumors.
  • Neurological oncologist. These oncologists treat people who have brain tumors and cancer that affects the nervous system.

What education do you need to become an oncologist?

All oncologists’ education begins with obtaining a bachelor’s degree and a medical degree. Oncologists who specialize in medical oncology, surgical oncology, radiation oncology or hematology oncology complete residencies and fellowship programs before obtaining certification.

Here are educational requirements for each specialty:

  • Medical oncology. Medical oncologists complete three-year internal medicine residencies, two-year oncology fellowships and obtain certification from the American Board of Internal Medicine. Most medical oncology fellowships combine medical oncology and hematology.
  • Surgical oncology. Surgical oncologists complete five- to six-year surgical residencies and two- to three-year surgical oncology fellowships.
  • Radiation oncology. Radiation oncologists complete five-year residencies that include one year of clinical training in internal medicine, pediatrics, surgery or surgery specialties, obstetrics and gynecology, family practice or transitional or categorical radiation oncology, and four years of training in radiation oncology. They also obtain certification from the American Board of Radiology.
  • Pediatric oncology. These specialists complete three-year pediatric residencies and obtain certification in general pediatrics from the American Board of Pediatrics. Then, they complete three-year fellowships in pediatric hematology-oncology before obtaining certification from the hematology-oncology sub-board of the American Board of Pediatrics.
  • Gynecologic oncology. Gynecologic oncologists complete four-year gynecology and obstetrics residency and three- to four-year fellowships. They obtain certification from the American Board of Obstetrics and Gynecology.
  • Neurological oncologist. Neurological oncologists complete residencies in neurology and/or medical oncology and neurosurgery. These residencies may take as many as seven years to complete. The residencies are followed by two- to three-year neurological oncology fellowships. They obtain certification from the United Council for Neurologic Subspecialties.


What are the reasons I might need to see an oncologist?

Different cancers affect your body in different ways. Generally speaking, you might see an oncologist if you talk to your primary care physician about a change in your body and they recommend you have some preliminary tests. You likely will be referred to an oncologist if your tests indicate you have cancer.

Does seeing an oncologist mean I have cancer?

No, seeing an oncologist doesn’t mean you have cancer. You’re seeing an oncologist because you have symptoms that might be cancer. Your visit to an oncologist is an opportunity for you to talk to a specialist about your symptoms. Your oncologist might order tests to learn more about your symptoms.


What should I expect during my first visit to an oncologist?

You’re seeing an oncologist because there’s reason to believe you might have cancer. At your first appointment, you and your oncologist will discuss your situation. They’ll ask about your medical history, such as other medical conditions and prior surgeries. If you were referred by another healthcare provider, they’ll review that healthcare provider’s notes.

Additional Common Questions

Why is cancer sometimes called oncology?

Cancer is an ancient illness. Centuries ago, early Greek and Roman physicians studying cancerous tumors likened cancer to a crab, possibly because spreading tumors resembled legs spreading out from crab bodies. Oncology — the study and treatment of cancer — takes its name from the Greek word “oncos,” which means swelling and refers to the way Greek physicians described how tumors grew.

A note from Cleveland Clinic

You might be anxious about seeing an oncologist because you’re worried you might have cancer. And if you’re diagnosed with cancer, you might be frightened by the news. You might be frustrated, too, because you have questions for which there are no easy or black-and-white answers. Your oncologist understands those feelings. They know what you’re going through. If you have cancer, every appointment is an opportunity to talk about your concerns and ask questions. Your oncologist is there to help you however they can.

Medically Reviewed

Last reviewed on 12/01/2021.

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