Radiation enteritis

Overview

Radiation enteritis is the inflammation of the intestines caused by radiation therapy, typically for abdominal, pelvic, or rectal cancers. Symptoms often include diarrhea, nausea, vomiting, and stomach cramps. While usually temporary, it can become chronic, leading to complications like anemia or bowel obstruction. Treatment focuses on symptom management, with severe cases potentially requiring tube feeding or surgery.

What Is Radiation Enteritis?

Radiation enteritis is a condition characterized by the inflammation and damage of the intestinal lining, specifically caused by exposure to ionizing radiation during cancer treatment. This damage can disrupt the normal functions of the intestines, leading to a range of gastrointestinal symptoms. The severity and duration of radiation enteritis depend on factors such as the radiation dose, the area of the body treated, and individual patient sensitivities.

Types of Radiation Enteritis?

Radiation enteritis can be categorized into two primary forms, categorized by their onset and duration relative to radiation therapy. 

• Acute Radiation Enteritis

Acute radiation enteritis develops during the course of radiation therapy. Its symptoms, which often include diarrhea, abdominal pain, and nausea, are typically temporary and tend to subside within a few weeks after the completion of the radiation treatment. This form is a direct, immediate response of the intestinal tissues to the radiation exposure.

• Chronic Radiation Enteritis

In contrast, chronic radiation enteritis emerges much later, sometimes months or even years after radiation therapy has concluded. The symptoms of chronic radiation enteritis are more persistent and can lead to long-term complications, such as intestinal narrowing (stricture), abnormal connections between organs (fistula), or an inability to absorb nutrients properly (malabsorption). This form indicates more lasting damage to the intestinal lining and function.

How Common Is Radiation Enteritis?

The prevalence of radiation enteritis has significantly decreased with advancements in radiation therapy techniques. Historically, with older methods of delivering radiation to the abdomen or pelvis, up to half of treated individuals might have developed the condition. However, modern radiation techniques, which allow for more precise targeting of cancerous cells and minimize exposure to healthy tissues, have considerably lowered the risk of chronic radiation enteritis.

Symptoms of Radiation Enteritis

Symptoms of radiation enteritis encompass:

• Diarrhea
• Nausea
• Vomiting
• Abdominal cramps or pain
• Bloated abdomen
• Pain when passing out stool
• Pain or bleeding in the rectal area
• An urgent or frequent need to have a bowel movement
• Decreased appetite
• Unintentional loss of weight

Usually, these symptoms diminish within several weeks after treatment ends. Yet, in some instances, they may endure for a longer period. Persistent radiation enteritis can result in complications like anemia and bowel obstruction.

Risks Factors of Radiation Enteritis

Patients receiving radiation therapy for abdominal and pelvic cancers are at a heightened risk of developing radiation enteritis. This condition stems from the intestinal irritation that can occur as a result of radiation therapy.

Some individuals are more vulnerable because of:

• Additional therapies like chemotherapy that cause cell death.
• Tissue inflammation brought on by illnesses such as pelvic inflammatory disease.
• Health conditions including diabetes and high blood pressure that reduce blood flow to the intestines.
• Damage to the tissue from previous abdominal procedures.
• Using tobacco in any form, including smoking.
• Malnutrition

Radiation Enteritis Diagnosis

Diagnosing radiation enteritis typically involves a thorough review of your medical history and a physical examination. To examine the small intestine, your doctor may perform an endoscopy, using a flexible tube with a camera inserted through your throat. Alternatively, a colonoscopy may be conducted to inspect the large intestine by passing the tube through your rectum. In some cases, a capsule endoscopy, which involves swallowing a pill-sized camera, may be utilized to capture images of the intestines. 

Additional diagnostic procedures may include imaging tests like 

• X-rays
• Computed Tomography (CT) scans
• Magnetic Resonance Imaging (MRI) scans.

Radiation Enteritis Treatment

The treatment for radiation enteritis usually centers on managing symptoms until they resolve. This condition arises from intestinal irritation following radiation therapy for cancer. Your doctor might recommend dietary changes and prescribe medications to alleviate diarrhea and pain. Antibiotics could be prescribed to tackle bacterial overgrowth.

If radiation enteritis persists, a feeding tube may be required. In rare cases, surgery might be considered to bypass the affected section of the intestine.

Radiation Enteritis Prevention 

• Utilizing advanced radiation delivery methods, such as intensity-modulated radiation therapy (IMRT), to precisely target cancerous areas and minimize exposure to healthy intestinal tissue.
• Employing custom positioning devices to ensure the patient remains still during treatment, further enhancing the precision of radiation delivery.
• Using protective shields for the bowel or rectum when feasible to physically block radiation from reaching sensitive areas.
• Discussing any existing health conditions, like diabetes, high blood pressure, or inflammatory diseases, with the healthcare team, as these can increase vulnerability.
• Maintaining good nutrition and avoiding tobacco use, as these factors can impact the intestines’ ability to withstand radiation.
• Considering dietary adjustments, such as avoiding high-fiber, greasy, spicy, or processed foods, and opting for easily digestible, nutrient-rich options during and after treatment.