SENSITIVITY, SPECIFICITY, AND PREDICTIVE VALUE OF FECAL OCCULT BLOOD TESTING (HEMOCCULT-II) FOR COLORECTAL NEOPLASIA IN SYMPTOMATIC PATIENTS - A PROSPECTIVE-STUDY WITH TOTAL COLONOSCOPY

Objectives: To evaluate the specificity, sensitivity, and positive pre dictive value of fecal occult blood testing (FOBT) in symptomatic pati ents, with colonoscopy as the gold standard, and to assess the usefuln ess of FOBT as an ancillary examination in symptomatic patients for wh om total colonoscopy is indicated. Methods: We studied 439 consecutive patients who underwent Hemoccult II testing before total colonoscopy, Results: The sensitivity, specificity, and positive predictive value for colorectal neoplasia (cancer and adenomatous polyps) was 76.5%, 56 .7%, and 27.6%, respectively, The sensitivity, specificity, and positi ve predictive value for colorectal cancer were 69.2%, 73.2%, and 7.3%, respectively, Conclusions: The sensitivity, specificity, and positive predictive value of FOBT are difficult to estimate from screening pro grams, because Hemoccult-negative individuals do not undergo examinati on of the colon, and many of the Hemoccult-positive cases do not under go total colonoscopy. With total colonoscopy serving as the gold stand ard, FOBT does not appear to be of much value as an ancillary examinat ion in patients with symptoms potentially attributable to the lower ga strointestinal tract.