Oncology: The field of medicine devoted to cancer.
In clinical oncology, there are three primary disciplines:
Medical oncology – the treatment of cancer with medicine, including chemotherapy.
Surgical oncology – the surgical aspects of cancer including biopsy, staging and surgical resection of tumors.
Radiation oncology – the treatment of cancer with therapeutic radiation. (Radiation oncology is also called radiation therapy or radiotherapy.)
Within these three primary disciplines, oncologists may and often do further specialize in specific types of cancer such as breast cancer, lung cancer, prostate cancer, leukemia, lymphoma, brain and spinal cord cancer (neuro-oncology), etc.
Pediatric oncology is usually recognized as a fourth, distinct discipline within the field of oncology. Pediatric oncologists specialize in the treatment of children with cancer and incorporate all three primary oncology disciplines in the care of their young patients. These cancer specialists require a special subset of skills because children with cancer have unique problems that require specialized pediatric care across the entire spectrum of treatment.
Once a cancer diagnosis is made, it is the oncologist's role to explain the cancer diagnosis and meaning of the disease stage to the patient; discuss various treatment options; recommend the best course of treatment; deliver optimal care; and improve quality of life both through curative therapy and palliative care with pain and symptom management.
Typically, when a tumor is discovered, a patient will first see a surgeon. The surgeon will perform a biopsy of the tumor and send the tissue to a pathologist for evaluation. If a cancer diagnosis is made, an oncologist will evaluate the patient to determine the stage of the cancer. Staging usually involves a precise evaluation of the tumor, lymph nodes, and any metastasis, or spread of the disease.
Cancer is best treated by a multi-disciplinary team of oncologists that typically includes at least two of the three primary oncology disciplines. In addition, the team usually includes a pathologist, a diagnostic radiologist, and an oncology nurse. The advantage of the team approach is that it combines the unique skill sets of several different disciplines into one consulting group, as cancer treatment frequently involves a combination of surgery, chemotherapy, and radiation.
In the case of a new or difficult cancer diagnosis, a tumor board will be called upon to review the case. Tumor boards consist of medical experts from all relevant disciplines who consult on the best course of treatment for an individual patient.
Clinical oncology is represented by a number of professional and lay medical organizations including, in the US, the American Society of Clinical Oncology and the American Cancer Society.
The word “oncology” means the study of tumors. The word comes from the Greek “o(n)glos” (a bulk or mass, or later, a tumor) + “logos” (a study or treatise) = the study of tumors.