New-Onset Gastrointestinal Polyposis in a 60-Year-Old Man with Cronkhite-Canada Syndrome

A 60-year-old man with a history of diarrhea, weight loss, and various ectodermal changes was diagnosed with Cronkhite-Canada syndrome (CCS), a rare, nonhereditary disorder characterized by gastrointestinal polyposis, diarrhea, weight loss, hypogeusia, onychodystrophy, alopecia, and skin hyperpigmentation. His symptoms improved after treatment with prednisone and azathioprine. CCS is associated with a high mortality rate and increased risk of colorectal cancer. The patient's abdominal CT and endoscopies revealed thickening of the gastric body and antrum, as well as numerous polyps and nodular mucosa in the colon. Biopsies indicated hyperplastic polyps and focal colitis. CCS affects all ethnic groups, has a slight male predominance, and the mean age of onset is 59 years. The polyps are typically hamartomatous and nonneoplastic, but dysplastic changes can occur, leading to a 25% lifetime risk of colorectal cancer. The exact etiology of CCS is unknown, but an autoimmune mechanism is proposed. Treatment is not standardized due to the rarity of CCS, but steroids and nutritional supplements are commonly used, with azathioprine for relapses. Resection may be necessary for any remaining polyps, especially if dysplastic changes are detected.