Radiation enteritis is a condition in which the lining of the intestine becomes swollen and inflamed during or after radiation therapy to the abdomen, pelvis, or rectum. The small and large intestine are very sensitive to radiation. The larger the dose of radiation, the more damage may be done to normal tissue. Most tumors in the abdomen and pelvis need large doses of radiation. Almost all patients receiving radiation to the abdomen, pelvis, or rectum will have enteritis.
Endometrial cancer is a disease that primarily affects postmenopausal women at an average age of 60 years at diagnosis. Risk factors include postmenopausal estrogen therapy, obesity, a high-fat diet, reproductive factors like nulliparity, early menarche and late menopause, polycystic ovarian syndrome, and tamoxifen use. Women with hereditary nonpolyposis colorectal cancer syndrome have a markedly increased risk of endometrial cancer compared with women in the general population.
Radiation therapy to kill cancer cells in the abdomen and pelvis affects normal cells in the lining of the intestines. Radiation therapy stops the growth of cancer cells and other fast-growing cells. Since normal cells in the lining of the intestines grow quickly, radiation treatment to that area can stop those cells from growing. This makes it hard for tissue to repair itself. As cells die and are not replaced, gastrointestinal problems occur over the next few days and weeks.
Doctors are studying whether the order that radiation therapy, chemotherapy, and surgery are given affects how severe the enteritis will be.
Symptoms may begin during radiation therapy or months to years later.
Radiation enteritis may be acute or chronic:
Acute radiation enteritis occurs during radiation therapy and may last up to 8 to 12 weeks after treatment stops.
Chronic radiation enteritis may appear months to years after radiation therapy ends, or it may begin as acute enteritis and keep coming back.
The total dose of radiation and other factors affect the risk of radiation enteritis.
Only 5% to 15% of patients treated with radiation to the abdomen will have chronic problems. The amount of time the enteritis lasts and how severe it is depend on the following:
The total dose of radiation received.
The amount of normal intestine treated.
The tumor size and how much it has spread.
If chemotherapy was given at the same time as the radiation therapy.
Symptoms of acute enteritis usually go away 2 to 3 weeks after treatment ends.
Symptoms of chronic enteritis usually appear 6 to 18 months after radiation therapy ends. It can be hard to diagnose. The doctor will first check to see if the symptoms are being caused by a recurrent tumor in the small intestine. The doctor will also need to know the patient's full history of radiation treatments.