Colorectal cancer screening: is one-year surveillance sigmoidoscopy necessary?

OBJECTIVES

To assess the diagnostic yield of the 1-yr follow-up flexible sigmoidoscopy examination for the detection of colonic neoplasia in a colorectal cancer screening program.

METHODS

Data were prospectively collected for flexible sigmoidoscopies performed between July 1991 and July 1992 as part of the University of South Alabama Colon Cancer Registry.

RESULTS

A total of 217 subjects with an age-related risk of colon carcinoma and no evidence of occult blood by stool examination were enrolled. One hundred and sixteen underwent initial sigmoidoscopic examination, and 101 had a 1-yr surveillance examination. Ten of the 116 patients (8.6%) undergoing initial surveillance sigmoidoscopy were found to have neoplastic lesions. In contrast, only 1/101 (1%) patients undergoing 1-yr follow-up surveillance sigmoidoscopy was found to have a neoplastic lesion. Neoplastic lesions in both groups were adenomas. No carcinomas were found.

CONCLUSIONS

These data suggest that the 1-yr surveillance sigmoidoscopy adds little to the diagnostic yield of colon cancer screening.