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Doctor, Doctor: Radiation therapy explained

Network - Summer 2013

Shalin Shah, M.D., is the center medical director at MD Anderson’s Regional Care Center in Sugar Land. His research concerns how diet, exercise and other integrative medicine strategies may improve the cure rates and side effects of treatment in cancer patients. This article originally appeared in MD Anderson’s Cancerwise blog.

Shalin Shah, M.D.

Regardless of where radiation fits into your cancer treatment plan, you may have questions about what you’ll experience during the therapy.

Here are a few things to know.

How radiation works

Receiving radiation is similar to receiving very strong X-rays.

Advances in the therapy allow us to pinpoint cancerous cells with amazing accuracy.

The goal of radiation is to kill the cancerous cells to both shrink a tumor and to prevent it from growing and spreading. We try to avoid normal tissue at the same time.

Common radiation myths

Patients often ask if radiation will make them glow in the dark. The answer is no.

And if you receive external radiation therapy or even some types of internal radiation, you won’t be radioactive or a hazard to anyone else.

Radiation side effects: What to expect

Most patients have side effects during radiation, but these may often be managed with simple measures.

Side effects vary from patient to patient and depend on where on the body radiation is delivered.

After a few treatments, patients may experience skin reddening, similar to a sunburn, at the point where the radiation was delivered. The skin may feel a little dry and even itchy, and some patients experience minor peeling.

Patients who need radiation in their abdomen or stomach may get diarrhea, though this can be managed with dietary changes and over-the-counter medication.

Hair loss is uncommon during radiation treatment, unless the brain is being treated.

During radiation therapy, some patients experience changes in taste and smell, and find that some foods they normally enjoy don’t taste the same. Most patients gradually regain their normal sense of taste and smell after therapy.

In addition, patients being treated for head and neck cancers may experience dry mouth syndrome. I always advise them to drink water and juice frequently to help with this.

Another common side effect of radiation treatment is fatigue, which can continue for a couple of months after treatments are complete. While there’s no surefire cure for fatigue, it’s best to prepare to experience some drowsiness and make simple lifestyle changes to help manage it. These changes include getting mild exercise, drinking plenty of fluids and taking time to rest.

Cancer can be exhausting, and patients need to take care of themselves and let others help them as much as possible. 

Maintaining a healthy, balanced diet may also help boost energy levels.

Every patient is unique

Like all aspects of cancer care, response to radiation therapy differs from patient to patient. So make sure you discuss anything you experience with your physician. We can often recommend ways to minimize discomfort during this step toward survivorship.

© 2015 The University of Texas MD Anderson Cancer Center