Screening flexible sigmoidoscopy by primary care physicians. Effectiveness and costs in patients negative for fecal occult blood.

A total of 252 consecutive screening flexible sigmoidoscopies were done by two community-based general internists on asymptomatic patients with stool negative for occult blood. Neoplastic lesions were found in 26 patients (10.3%), including 27 adenomatous polyps, 2 with carcinoma-in-situ and 1 carcinoid tumor. No complications resulted from flexible sigmoidoscopy. Nineteen patients with positive screening sigmoidoscopy underwent colonoscopy, and additional adenomatous polyps were found in six patients (31.6%), but no additional malignancy. Total cost for screening flexible sigmoidoscopy and additional studies was $30,359 ($1,168 per patient with a polyp or malignancy and $10,119 per patient with a malignant lesion). Screening flexible sigmoidoscopy can be safely done by community-based general internists in asymptomatic patients with a diagnostic yield comparable with that reported by subspecialists; total costs are acceptable.