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What Is a Radiation Oncologist?

Radiation Oncologists

What Is a Radiation Oncologist?

Radiation oncologists are doctors who have completed medical school as well as an internship in internal medicine or surgery. 

They use computers and sophisticated software to determine the best approach of delivering radiation therapies to treat cancer patients and those with benign disease.

Sometimes their goal is to reduce the size of cancerous tumors or eradicate them altogether. Other times, radiation oncologists administer radiation as a palliative treatment to reduce pain and help to improve their patients’ quality of life.

They lead our internal team of radiation oncology professionals including medical physicists, dosimetrists, radiation therapists and oncology nurses.

Radiation oncologists are part of a multi-disciplinary care team that includes medical  oncologists, radiologists and interventional radiologists, surgical oncologists, reconstructive surgeons, pathologists, palliative care, genetic experts, highly experienced nurse navigators and other specialists. This team approach to care ensures that our patients receive the benefit of the team’s collective experience, which leads to higher quality care.

What Is Their Training?

They have completed a residency program consisting of four years of specialty training. Some may complete a fellowship to gain further knowledge of a particular specialty. As doctors, they are educated about cancer and have a full understanding of the disease, its biology and how it spreads.

The Radiation Oncology Team Includes:

Medical Physicist

A medical physicist commissions and checks the performance of our radiation through daily quality assurance metrics and ensures that the staff and public near the treatment center are not exposed to accidental radiation. They work closely with radiation oncologists on treatment planning and delivery of the radiation, to ensure safe and accurate treatments. Medical physicists oversee the work performed by dosimetrists.

They Research, develop and evaluate new techniques, and direct training and quality control programs for both the equipment and procedures. Medical physicists oversee safety testing on the equipment to ensure that it is working correctly.

Typically, medical physicists have earned a master’s degree or doctorate along with two years of training in clinical physics. They hold certifications by either the American Board of Medical Physics or the American Board of Radiology.

Radiation Therapist

Radiation therapists administer daily radiation treatments under the direction of a radiation oncologist.

They are specially trained and certified technicians who work with directly patients. An important part of their job is to position the patient on the treatment table according to the exact specifications on the treatment plan ordered by the radiation oncologist. Once positioned using lasers to approximate the treatment plan, additional image guidance is employed by the therapists to dial in the target to millimeter accuracy. This helps to ensure that the patient receives the radiation in the exact area that requires treatment and protects them from unnecessary radiation exposure.

They have completed and educational program and are certified by the American Registry of Radiologic Technologists and are licensed by the State of Arizona.


Dosimetrists work with radiation oncologists and the medical physicists to create individual treatment plans for each patient.

They can be thought of like pharmacists who, instead of measuring and preparing drugs, measure and prepare the computerized radiation plan. Using treatment planning software, they calculate the specific dose of radiation that can be tolerated based on where the tumor is located, while sparing normal tissues. Their work is overseen by the medical physicist, and the treating physician.

Dosimetrists start as radiation therapists but have additional, intensive training. They are certified by the Medical Dosimetrist Certification Board.

Radiation Oncology Nurse

Nurses have an important role in evaluating a patient before treatments begin. They also may help the patient with understanding potential side effects, and how best to manage them. Their continual assessment of any problems or concerns that the patient may experiencing is shared with the other members of the radiation oncology team.

They are registered nurses, and many have an additional accreditation in oncology nursing. Advanced practice oncology nurses are nurse practitioners or clinical nurse specialists who have earned a master’s degree.