A 70-year-old woman with a history of ovarian cancer presents with diarrhea. She completed radiation therapy for her cancer 3 months ago. Physical examination shows cachexia, hyperactive bowel sounds, and generalized pallor. The stools are found to contain blood. A CBC shows decreased hemoglobin (7.8 g/dL) and decreased mean corpuscular volume (70 mm3). Which of the following is the most likely cause of GI bleeding in this patient?
High-Yield Explanation
Radiation therapy for malignant disease of the pelvis or abdomen may be complicated by injury to the small intestine and colon. Clinically significant radiation enterocolitis is most common in the rectum. The lesions produced by radiation therapy range from a reversible injury of the intestinal mucosa to chronic inflammation, ulceration, and fibrosis of the intestine.Diagnosis: Radiation enterocolitis, ovarian cancer