Radiation therapy: What it is and what to expect

More than half of cancer patients will receive radiation therapy, but what is it? Does it hurt? And what are the side effects? We spoke with Cullen Taniguchi, M.D., Ph.D., to answer some common questions about radiation therapy. Here’s what he had to share. How does radiation therapy work? Radiation therapy uses high-energy waves, like those used with an X-ray, but at a higher energy that damages tumor cells’ DNA. The tumor cells die, but the surrounding normal tissues heal themselves. When is radiation therapy typically used? There are three ways radiation is used. Most commonly, radiation is used before surgery to shrink a tumor so that it’s easier to remove. We also give radiation after surgery to help destroy any remaining cancer. And when tumors can’t be easily removed with surgery, we’ll use radiation instead. What are the different types of radiation therapy? Brachytherapy allows us to put radiation up close to the tumor. But we can only do this safely with a few tumor types, such as with prostate cancer, cervical cancer and breast cancer. A second type of radiation uses photons, which you may know as X-rays. We first identify the tumor’s location with a CT scan. Then, we develop a plan to ensure as little normal tissue is exposed to radiation as possible. Intensity-modulated radiation therapy (IMRT) is a type of photon therapy that uses a powerful computer to help develop the treatment plan. The computer uses multiple angles to identify the best approach to kill the tumor and limit exposure to normal tissue. IMRT is used when a tumor is close to sensitive organs,...