Background: Current screening protocols for colorectal cancer depend primarily on fecal occult blood testing (FOBT). However, positive test results do not always indicate the presence of a colonic neoplasm.
Methods: We reviewed the results of 100 consecutive bidirectional (upper and lower) endoscopic procedures performed to evaluate positive FOBT results. Patients were excluded if they presented with gross bleeding, a history of bowel lesions, or previous intestinal operations. There were 31 women and 69 men whose mean age was 51 years.
Results: Major abnormalities were found on esophagogastroduodenoscopy (n = 24), colonoscopy (n = 13), or both studies (n = 2). Active bleeding was manifested in two patients, (Barrett's ulcer, duodenal arteriovenous malformation). Two other patients had malignancy: One had a cecal adenocarcinoma and the other a gastric adenocarcinoma. Various benign lesions also were identified in the stomach including esophagitis (n = 8), ulcers/erosions (n = 8) varices (n = 5), and arteriovenous malformations (n = 2). Colonic pathology included polyps (n = 8), arteriovenous malformations (n = 3), and rectal varices (n = 1). Diverticulosis and hemorrhoidal disease were present in 29 and 16 patients, respectively, but were not considered to be likely sources of a positive FOBT.
Conclusion: Positive FOBT results may indicate the presence of either upper or lower intestinal pathology, and bidirectional endoscopy is an efficient and accurate technique for the comprehensive evaluation of occult bleeding.