Radiation Therapy - Reminder of Process - Quiz on Monday

Radiation therapy

Radiation therapy is an important part of the treatment of high-grade gliomas. In typical situations, patients begin radiation treatments within 2 to 4 weeks after tumor resection. A physician who supervises radiation treatments is called a radiation oncologist.

Following a "simulation" session in which the radiation oncologist plans the shape of the radiation beam as well as dose, treatments are given daily, Monday through Friday, for 4 to 6 weeks. Each treatment takes only a few minutes. During radiation, patients are seen weekly by the radiation oncologist, and a nurse is available for questions every day. Most patients feel better during radiation therapy if they are taking a small dose of a steroid which reduces brain swelling, called Decadron (also called dexamethasone).

There are usually no immediate side effects during each treatment. As the treatment progresses, hair loss will occur over the area where the radiation beam passes into the tumor. Most patients experience some fatigue by the second or third week. For many, a 30 minute nap is helpful every afternoon. There are a number of long-term side effects from radiation therapy, ranging from those that are a minor nuisance to ones that can produce major health problems. Fortunately, serious side effects are rare. Furthermore, the potential risks of radiation therapy are outweighed by the known risk of not treating the tumor. The radiation oncologist will describe these risks prior to starting therapy.

An MRI is usually obtained about 2 to 4 weeks after the end of radiation therapy in order to judge the effect of treatment. Most of the time this scan will show no change from the post-operative MRI, which is good. Some shrinkage is even better. Growth during radiation therapy is an unwanted sign of an aggressive tumor.