Faculty Bibliography

OBJECTIVES: Annual fecal occult blood testing (FOBT) is often continued in patients who have had a recent negative colonoscopy, despite recommendations to the contrary. This prospective study aimed to determine the proportion of patients with a positive FOBT who had adenomas and cancers on colonoscopy stratified according to the duration of time since the last negative colonoscopy. METHODS: A total of 1,119 asymptomatic average-risk patients >/=50 years of age referred for a positive FOBT were prospectively identified and stratified by the duration of time since the last colonoscopy (never, >10 years, 5-10 years, or <5 years). The proportion of patients in each category with adenomas of any size, adenomas >/=10 mm, advanced neoplasms, and cancers was assessed. RESULTS: The mean age (68.9+/-9.6 years), sex (95.2% male), and race (48.1% white, 32.1% black, 15.6% Hispanic, and 4.2% other) did not differ between the four groups. Overall, adenomas of any size were detected in 42.8% of patients, adenomas >/=10 mm in 14.7%, advanced neoplasms in 20.7%, and cancers in 7.3%. Advanced neoplasms were detected in 30.4% of patients who have never had a colonoscopy, 27% in those who have had one greater than 10 years prior, 10.0% in 5-10 years prior, and 1.1% in less than 5 years prior. CONCLUSIONS: In asymptomatic average-risk patients with a negative colonoscopy within the last 5 years, the prevalence of adenomas is low, and no patient was diagnosed with cancer. These findings support the CDC recommendations to suspend annual FOBT for up to 5 years after a negative colonoscopy.Am J Gastroenterol advance online publication, 4 August 2015; doi:10.1038/ajg.2015.234.