What Does a Radiation Oncologist Do?

Radiation oncologists use ionizing radiation and radioactive drugs to attack tumors.
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Many once-dangerous cancers can now be treated successfully through varying combinations of surgery, chemotherapy and radiation therapy. Most cancer patients receive some form of radiation, which is overseen by a specialized doctor called a radiation oncologist. These physicians usually work as part of a collaborative team with other health care providers.


    Radiation oncologists collaborate with other physicians to identify and locate the cancer, and decide how radiation will fit into the overall plan of treatment. There are three basic approaches to radiation therapy. Sometimes it's applied externally, through powerful beams of focused X-rays or gamma rays. Another approach implants small pellets of radioactive material near the tumor, to attack it over a longer period. A third uses radioactive drugs, called radiopharmaceuticals, which carry radioactivity to the cancer through the blood or other body systems. These techniques can be the primary treatment, or a complement to surgery or chemotherapy.


    Once the radiation oncologist settles on a specific course of treatment, other specialists must be involved in the process. The oncologist often consults with a medical physicist, who maintains and calibrates the machines and can help determine the best way to attack the tumor. A second specialist, the dosimetrist, calculates the optimum dosages, which are administered by a radiation therapist. These professionals and many others work under the direct supervision of the radiation oncologist, who holds ultimate responsibility for the course of treatment.

Balancing Act

    The radiation oncologist's work involves a complex balancing act. Radiation therapy works by interfering with the cancer cells' ability to reproduce, but unfortunately it also damages healthy tissues. Maximizing damage to the cancer, while minimizing risk to healthy tissues, is one of the radiation oncologist's fundamental duties. Some healthy tissues, such as the reproductive organs, are especially susceptible to damage and require extra care. The radiation oncologist can use a variety of creative techniques to reach those goals. That might include approaching the tumor from an unusual angle, using protective shielding, or varying the length and intensity of the treatments.

Other Roles

    Although a radiation oncologist primarily treats patients for therapeutic purposes, radiation can also be used as a palliative treatment. Some tumors cause great pain or interfere with eating, breathing or other fundamental processes. The radiation oncologist uses radiation therapy to shrink those tumors, reducing pain and helping restore the patient to a higher level of function. The oncologist might also be called upon by other oncologists and hematologists in an advisory role, to contribute to an overall plan of cancer care.

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