Radiation proctocolitis

Background

• Injury to the colon following radiation therapy most commonly affecting the sigmoid colon and rectum.
• Results in majority from radiation to the lower abdomen and pelvis as in the cases of cancers of the rectum, colon, gonads, uterus, bladder, and prostate.
• Occurs up to 6 weeks after receiving radiation therapy

Clinical Features

• Uncomplicated
  • Diarrhea
  • Urgency
  • Mucus discharge
  • Tenesmus
  • Bleeding is more common in chronic radiation proctitis than acute radiation proctitis

• Complicated
  • Radiation injury extending to genitourinary system
    • urethral stenosis
    • Cystitis
    • Ureteral scarring

• • Radiation injury extending to small bowel
    • Small bowel obstruction
    • Small intestine bacterial overgrowth
    • Fistulae

Differential Diagnosis

• Ulcerative colitis
• Crohns disease
• Inflammatory Bowel Disease
• CMV Colitis
• Infectious/parasitic enterocolitis
• Diversion colitis
• Ischemic colitis
• Diverticular colitis
• Chronis graft-versus-host diease

Evaluation

• Labs
  • Stool C.diff toxin along with routine stool cultures
  • Specific testing for E.coli 0157:H7
  • Ova and Parasite assay including giardia
  • CBC, electrolytes, albumin, ESR, CRP

• Endoscopy and biopsy
  • Nonspecific findings
  • Pallor, friability
  • Telangiectatic
  • Avoid this procedure in severe proctitis as it may facilitate fistula formation

• Imaging
  • CT if obstructive symptoms are present
  • MRI if suspicion is high for radiation-induced fistulae

Management

• Acute radiation proctitis
  • Generally self-limited
  • approximately 20% of patients will need to lengthen time intervals between radiation therapy to recover
  • Hydration, steroids, +/- 5-aminosalicylate enema.

• Chronic
  • Non-invasive
    • anti-inflammatories
    • sucralfate
    • short-chain fatty acids
    • Hyperbaric O2
    • Antioxidants

• • Invasive
    • ablation surgery
    • Resection if localized

Disposition

• Treat outpatient
• Severe cases that are candidates for surgery should be admitted

References

1. Do, Nhue L., et al. “Radiation Proctitis: Current Strategies in Management.” Gastroenterology Research and Practice, vol. 2011, 2011, pp. 1–9., doi:10.1155/2011/917941.
2. Gilinsky NH, Burns DG, Barbezat GO, et al. The natural history of radiation-induced proctosigmoiditis: an analysis of 88 patients. Q J Med 1983; 52:40.
3. Tagkalidis PP, Tjandra JJ. Chronic radiation proctitis. ANZ J Surg 2001; 71:230.
4. Shepherd NA. Pathological mimics of chronic inflammatory bowel disease. J Clin Pathol 1991; 44:726.