What is External Beam Radiation Therapy (EBRT)?

Question: What is External Beam Radiation Therapy (EBRT)?

External Beam Radiation Therapy is often used to treat prostate cancer. What is it? What are the side effects? When is it used?

Answer: External Beam Radiation Therapy (EBRT) is a treatment for prostate cancer where X ray radiation is used to kill prostate cancer cells by damaging their DNA. EBRT has been used to treat prostate cancer since the 1950s, and is the most commonly used type of radiation therapy for treating cancer. The equipment is similar to a standard X ray, and treatment is often performed on an outpatient basis.

EBRT is completely noninvasive, and the patient is in no discomfort during the X ray treatment. The exposure time to X rays is longer than with standard X rays, often several minutes, but once the machine is turned off, there is no residual radiation.

An EBRT treatment course typically runs once per day for five days a week, and treatment for localized prostate cancer (T2/T3) generally requires about two months of treatment sessions.EBRT can also be used to irradiate prostate cancer that has spread to other areas.

Side Effects of EBRT

Common side effects of EBRT are usually related to burns in the treated area. Because the bladder and urethra can be exposed to X ray radiation, you may experience burning with urination, increased urine frequency and a weakened urine stream from localized swelling and inflammation. Other areas commonly affected include the bowel, and skin around the rectum. This can result in diarrhea, abdominal tenderness, and skin irritation around the rectum. As with all cancer treatments fatigue and lowered blood counts are a sometimes experienced. Most of the time, symptoms are usually mild, and generally disappear within a couple of months after treatments end. Your physician may recommend a specific diet, or manage the symptoms with medications to minimize your discomfort. About one in five men treated with EBRT will experience long term bowel irritability which can require medical management.

Some more rare complications can include bladder irritability, permanent urethral narrowing, significant rectal bleeding, and temporary loss of sexual function. Long term erectile dysfunction after EBRT varies widely based on such things as cancer extent, use of hormone therapy, and existence of other medical conditions contributing to loss of sexual function.