Five-year follow-up of asymptomatic patients with negative fecal occult blood test results in whom clinically significant colorectal pathology was detected

OBJECTIVES: To determine from a 5-yr longitudinal study (a) rate of compliance with follow-up, (b) number of new clinically significant colorectal lesions discovered by sigmoidoscopy or colonoscopy at later examination, (c) number and causes of deaths, and (d) rate of diagnosis of new cancers among 36 asymptomatic patients with negative fecal occult blood tests in whom clinically significant colorectal lesions were found initially by 60-cm flexible sigmoidoscope. METHODS: For the 36 patients, medical records were reviewed throughout the 5-yr study period. These records included pathology reports, results from 60-cm sigmoidoscopy and colonoscopy examinations, and notations from visits to health facilities for reasons other than colorectal examinations. RESULTS: Seventy-one clinically significant lesions were removed during the 5-yr period; 58 were discovered by sigmoidoscopy and 13 by colonoscopy. Also, during the 5-yr period, noncolorectal cancer was diagnosed in six patients, and two patients died of cardiac disease. CONCLUSIONS: Patients who have clinically significant colorectal pathology found by 60-cm sigmoidoscope have a high prevalence of lesions beyond the view of this instrument. Therefore, colonoscopy should be performed when sigmoidoscopy shows clinically significant pathology. Because subsequent examinations show a high incidence of new lesions, rescreening is indicated.