April 30, 2017
2 min read

What is an oncologist?

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An oncologist is a physician who works in the field of oncology, the branch of medicine that deals with cancer.

The three main fields that oncologists work in are radiotherapy, surgical and medical.

Other common oncology specialties include gynecologic — which deals with the treatment of women with cancer of the female-specific organs — and pediatric — which is related to the treatment of children with cancer. Diagnosis and treatment of blood cancers, like leukemia and lymphoma, fall under the hematology-oncology specialty.

Becoming an oncologist

The training required to become an oncologist — and later to become a subspecialist in medical oncology, radiation oncology or other disciplines — is extensive.

The requisite 4 years of premedical education at a college or university is followed by 4 years in medical school to earn an MD or DO, then postgraduate training is obtained through internships or residencies. Lastly, a focus on internal medicine for 3 to 7 years is also required.

Oncologists additionally must pass an exam to gain a license to legally practice in their state. Specialists must also be certified by an independent specialty board, after meeting education and training requirements and passing an exam. Subspecialists in medical oncology or radiation oncology must have at least 1 additional year of training in those fields.

Oncologist job description

Oncologists diagnose cancer using biopsy, endoscopy, X-ray, CT scanning, MRI, PET scanning, ultrasound or other radiological methods. Nuclear medicine, as well as blood tests and tumor markers are also used for diagnosis.

Once a diagnosis is made, oncologists discuss the disease type and stage with the patient. Staging helps dictate the type of cancer treatment the patient receives.


A pathologist is a physician who examines cells and tissues under a microscope, then writes the pathology report. A pathology report explains a cancer diagnosis and stage of disease. This information helps to determine treatment for the patient. Pathologists typically send the pathology report to the oncologist within 10 days after biopsy or surgery.

Oncology treatment

One of the most common oncology treatments is chemotherapy. Oncologists oversee and coordinate oncology treatment, and specialize in the use of medications, such as chemotherapy, hormones and analgesics to manage disease. Oncologists often coordinate care with radiation and surgical oncologists.

Radiation oncologists use high-energy X-rays to destroy cancer cells. Radiation can be given as curative treatment, or in combination with chemotherapy and/or surgery. Patients with incurable cancers may also be seen by radiation oncologists for symptom relief.

Surgical oncologists are surgeons who specialize in the surgical treatment of cancer and malignant disease. They work closely with oncologists either before or after surgical removal of tumors to provide effective care. Compared with non-surgical oncology, the training for surgical oncologists is highly competitive and requires general surgery residency training. Palliative care may also be used by oncologists to treat pain and other symptoms of cancer.

Additional information can be found by searching the following websites: