Adequacy of follow-up after an abnormal fecal occult blood test (FOBT) result

Abstract

6035 Background: Annual fecal occult blood testing (FOBT) is the only colon cancer screening shown to reduce colon cancer incidence and mortality in randomized controlled trials. The true benefits of screening are only realized when total colon examination (TCE) is performed as follow-up to an abnormal screening result. Methods: We used the 2000 National Health Interview Survey (NHIS) Cancer Control Supplement, a nationally representative sample of households, to examine follow-up after abnormal FOBT and the content of this follow-up. Persons who reported undergoing an FOBT were the population of interest. Reasons for FOBT, results of test, and follow-up after an abnormal FOBT were examined. Inadequate follow-up after a positive FOBT included no follow-up or another FOBT. TCE was defined as sigmoidoscopy with double contrast barium enema (DCBE) or colonoscopy. We used SUDAAN to obtain population estimates. Results: We included 4,908 respondents who indicated they had undergone FOBT (79.8% as part of the routine physical examination, 14.7% for a specific problem, 2.0% as follow-up of a previous abnormal test/screening examine, 1.4% family history). Overall, 5.7% of respondents reported an abnormal test, varying by reason for test (3.5% for screening and 16.9% for those who had FOBT done for a specific problem). For those reporting an abnormal FOBT during screening, 62.9% had some follow-up diagnostic procedures. Fifty-three percent reported having a TCE as defined above. Forty-seven percent either had no further evaluation, another FOBT or incomplete colon examination with sigmoidoscopy alone, and DCBE only or a surgical evaluation. Those who had FOBT completed for a specific problem had more surgical evaluations (18.4%) and fewer TCEs (44.3%). Conclusions: Among a nationally-representative sample of adults who reported FOBT as a screening test for colorectal cancer, close to 63% had some type of follow-up. Only 53% of those with a positive screening FOBT had a TCE. These results suggest that the full potential of CRC screening is not being realized, and point to the need to improve follow-up of abnormal FOBT results. No significant financial relationships to disclose.