A 27-year-old woman with an 8-year history of ulcerative colitis is evaluated during a follow-up examination. The initial colonoscopy after diagnosis showed pancolitis. She has been treated with mesalamine since diagnosis and has had episodes of bloody diarrhea two or three times a year but has otherwise been well. Her most recent colonoscopy 1 year ago when she had increased diarrhea and bleeding showed no progression of disease. Since then, she has been clinically stable. The patient's medical history is otherwise unremarkable, and her only medications are low-dose mesalamine and a multivitamin. There is no family history of colorectal cancer.
On physical examination, vital signs are normal. There is mild abdominal tenderness in the right lower quadrant without rebound or guarding. The rest of the physical examination is normal.
Laboratory studies reveal a normal complete blood count, including leukocyte differential, and a normal serum C-reactive protein level.
The most appropriate management for this patient is annual colonoscopy beginning now. This patient has pancolitis of 8 years' duration. The inflammation involves the ileum and proximal colon. The colon cancer risk in patients with ulcerative colitis or Crohn disease reaches a significant level (estimate annual cancer risk of 1% to 2% per year) after 8 years of inflammation. The cancer risk is slightly delayed for patients with inflammation limited to the distal colon. The recommendation is to initiate a surveillance program with colonoscopy 8 years after onset of disease, with follow-up colonoscopy every 1 to 2 years thereafter. Random biopsies are performed in four-quadrant fashion throughout the entire colon. Colectomy is recommended for patients with dysplastic findings on biopsy.
In wireless capsule endoscopy, a patient swallows a video capsule that by intestinal motility passes through the stomach and into the small intestine. The video capsule transmits images to a recording device worn by the patient. The images are downloaded onto a computer where they can be reviewed. With capsule endoscopy, the small bowel can be visualized in its entirety. There is no recommendation for standard screening for small-bowel carcinoma in the setting of ulcerative colitis or Crohn disease, and therefore, capsule endoscopy is not indicated. Furthermore, capsule endoscopy has no ability to biopsy the bowel wall and assess for dysplasia. Flexible sigmoidoscopy would not reach the at-risk colonic mucosa in the proximal colon beyond the reach of the sigmoidoscope, and annual fecal occult blood testing is insensitive to the diagnosis of colonic dysplasia, the earliest precursor of colon cancer.
- Patients with inflammatory bowel disease should initiate screening for colorectal cancer after 8 years' disease duration.