Radiation proctitis
| Radiation proctitis | |
|---|---|
| Other names | Radiation proctopathy, Radiation associated vascular ectasias (RAVE) |
flexible sigmoidoscopy | |
| Differential diagnosis | Infectious proctitis, inflammatory bowel disease |
| Treatment | Endoscopy with argon plasma coagulation, bipolar electrocautery, radiofrequency ablation |
Radiation proctitis or radiation proctopathy is a condition characterized by damage to the rectum after exposure to
Signs and symptoms
Acute radiation proctopathy often causes pelvic pain, diarrhea, urgency, and the urge to defecate despite having an empty colon (tenesmus).[4] Hematochezia and fecal incontinence may occur, but are less common.[4] Chronic radiation damage to the rectum (>3 months) may cause rectal bleeding, incontinence, or a change in bowel habits secondary. Severe cases may lead to with strictures or fistulae formation.[5][4] Chronic radiation proctopathy can present at a median time of 8-12 months following radiation therapy.[4]
Histopathology
Acute radiation proctopathy occurs due to direct damage of the lining (epithelium) of the colon.[1] Rectal biopsies of acute radiation proctopathy show superficial depletion of epithelial cells and acute inflammatory cells located in the lamina propria.[4] By contrast, rectal biopsies of RAVE and chronic radiation proctopathy demonstrates ischemic endarteritis of the submucosal arterioles, submucosal fibrosis, and neovascularization.[4]
Diagnosis
Where chronic radiation proctopathy or RAVE is suspected, a thorough evaluation of symptoms is essential. Evaluation should include an assessment of risk factors for alternate causes of proctitis, such as
Endoscopy is the mainstay of diagnosis for radiation damage to the rectum, with either
Classification
Radiation proctitis can occur a few weeks after treatment, or after several months or years:
- Acute radiation proctitis — symptoms occur in the first 3 months after therapy.defecate.
- Radiation associated vascular ectasias (RAVE) and chronic radiation proctopathy — previously known as "chronic radiation proctitis" occur 3-6 months after the initial exposure. RAVE is characterized by rectal bleeding, chronic blood loss and anemia. Chronic radiation proctopathy is characterized by urgency, change in stool caliber and consistency and increased mucus. Severe cases may present with fistulas and strictures which are rare.[2]
Treatment
Several methods have been studied in attempts to lessen the effects of radiation proctitis. Acute radiation proctitis usually resolves without treatment after several months. When treatment is necessary, symptoms often improve with hydration, anti-diarrheal agents, and discontinuation of radiation.[4] Butyrate enemas may also be effective.[9][10]
In contrast, RAVE and chronic radiation proctopathy usually is not self-limited and often requires additional therapies.
In rare cases that do not respond to medical therapy and endoscopic treatment, surgery may be required. Overall, less than 10 percent of individuals with radiation proctopathy require surgery.[4] In addition, complications such as obstruction and fistulae may require surgery.
Epidemiology
Up to 30 percent of individuals who receive pelvic radiation therapy for cancer may develop radiation proctopathy.[4]