Whats the difference? Radiology and radiation therapy

a radiology technician observing computer screens during a scan
Radiology and radiation therapy are critical components to many cancer diagnoses and treatments, but because of their similar names, patients often get confused by what exactly each does for them.

Radiology and radiation therapy are critical components to many cancer diagnoses and treatments, but because of their similar names, patients often get confused by what exactly each does for them. Even though the names of the two fields of medicine share the same root, they use dramatically different technologies and techniques, and have wholly different purposes. X-rays, CT scans and other diagnostic imaging procedures—all radiology techniques—are used to help locate, stage and diagnose cancers. Radiation therapy is a treatment that uses high doses of targeted energy to kill cancer cells and shrink tumors.

While patients are typically more familiar with radiology procedures because they have encountered them at other times in their lives, some find radiation therapy both foreign and intimidating. The idea of radiation—something they are told to otherwise avoid—being pumped into their bodies is counter-intuitive to some people, and the dark rooms, giant machines, buttons and lights may be unnerving. Radiation also differs distinctly from other cancer treatments in that it is invisible to the naked eye. Surgery, on the other hand, involves removing all or part of a tumor. Chemotherapy, immunotherapy and other medications are delivered in pill or liquid form. "Radiation is very intangible to people," says Anderson Bauer, MD, Radiation Oncologist at our hospital in Phoenix. "You can't feel it. You can't see it or taste it. Every now and then, someone says they can smell it, but this is actually due to some patients detecting the scent of ozone created by radiation interacting with the air.” That’s why many patients benefit from an explanation of how radiation therapy works. “ I explain how the radiation comes out of the machine very much like light will come out of a hole By explaining things in a way that people are familiar with, it allows them to better understand what we do,”  says Anderson Bauer, MD, Radiation Oncologist at our Phoenix hospital.

Other doctors and other clinicians on a cancer patient’s care team may also have similar titles starting with “rad.” "Our primary focus is in using ionizing radiation energy to treat cancer, whereas the diagnostic radiologists are using ionizing radiation to evaluate patients with imaging. And sometimes that’s confusing to people," Dr. Bauer says. Each performs specific duties that differentiate him or her from others on the team. For example:

Radiation therapists set up the equipment and deliver radiation treatments prescribed by a radiation oncologist. Radiation therapists are not doctors, but are highly trained to operate a variety of sophisticated radiation therapy equipment used in cancer treatment.

Radiographers set up and perform X-rays, CT-scans, MRIs and other diagnostic imaging tests and pass the results on to a radiologist for interpretation.

Radiologists are doctors trained to read and interpret imaging scans to help diagnose injuries and disease. Diagnostic radiologists may have specialized training in specific fields, such as mammography or imaging of the gastrointestinal tract.

Radiation oncologists are doctors who specialize in using radiation to treat cancer. Radiation oncologists may also be part of a larger care team, working with medical oncologists, surgeons or supportive care experts to develop treatment plans and help patients manage side effects.

Interventional radiologists are doctors who diagnose and treat a variety of diseases, including cancer, using minimally invasive procedures, typically as an alternative to open surgery. For example, they may use image-guided technology to place stents and catheters. For cancer patients, they may use chemoembolization to cut off the blood supply to a tumor or radiofrequency ablation to damage cancerous tissue.

Dr. Bauer says patients should feel empowered to ask questions about their treatment plans and about the men and women delivering their care, to help cut through the confusion they may encounter during cancer treatment. "By having a very comfortable atmosphere for patients, most people can get to where they understand the treatment strategy," he says. "And when people know what the strategy is, they can feel more comfortable and confident in their treatment.”