Can you tell me anything about radiation damage? I underwent radiation therapy for cervical cancer four years ago. For the last two months, I have thrown up everything and had constant diarrhea, recently with blood. My dad has Crohn's disease, but the specialist doesn't think that's my problem. He mentioned damage that happens a couple of years after radiation in some patients. What do you think?

Q.

Using radiation to treat a cancer of the abdomen or pelvis (as in cervical cancer) can lead to radiation-induced inflammation of the small or large intestine (enteritis or colitis). Radiation is an effective cancer treatment because it can eliminate rapidly growing cells, and tumor cells tend to grow very rapidly. Thus, tumors tend to shrink, while surrounding cells are not as severely affected. However, since the cells lining the intestine also grow quickly, they are also often damaged by radiation.

Such intestinal damage is not as common today as it was in the past due to technological advances in the administration of radiation, but it still can occur. Radiation effects on the intestine can occur soon after the therapy. Nausea, vomiting, abdominal pain and diarrhea are common symptoms. These will usually go away spontaneously. Chronic damage -- usually scarring and obstruction of the small intestine -- may appear months to even several years after the radiation was given. Nausea, vomiting, abdominal cramps and diarrhea are typical symptoms. Radiation can also lead to formation of small abnormal blood vessels in the colon and rectum that bleed easily. Thus, the symptoms that you are experiencing could potentially stem from chronic radiation-induced damage of the intestine.

However, you must consider other potential causes for your symptoms. Intestinal adhesions, hernias, inflammatory conditions (such as Crohn's disease) and tumors can also produce these symptoms. A careful evaluation by a gastroenterologist will help determine the likely cause of your symptoms. Certain diagnostic tests, including endoscopic procedures and contrast examinations of the digestive tract, may also be helpful. Your therapy will depend on the cause of your problems, which is why it is crucial that you get an accurate diagnosis.