Gellad ZF (Durham VAMC), Provenzale DT
(Durham VAMC), Fisher DA
The VA healthcare system recently issued a directive calling for positive fecal occult blood tests (FOBT) to be followed by complete colon evaluation with colonoscopy within 60 days. However, there is no published evidence defining the optimal time from positive screen to follow-up testing. We examined the distribution of time to colonoscopy at a single VA center to better understand the process of care prior to the release of this directive.
Subjects were consecutive patients at a single VA facility age 50 and older, with positive screening FOBT between March 1, 2000 and February 28, 2001 and a colonoscopy within 18 months. The primary variable of interest was time from positive FOBT to colonoscopy. Findings on colonoscopy were classified into four categories by most advanced lesion: no adenoma, adenoma, advanced adenoma, or invasive cancer. Advanced adenomas were defined as adenomas with a diameter of 10mm or more, villous adenomas, adenomas with high-grade dysplasia, or intramucosal carcinoma.
Two hundred and fifty-five subjects were included. The majority of subjects were male. The distribution of findings was as follows: 48.6% no adenomas, 36.5% adenomatous polyps, 11.4% advanced adenomas, and 3.5% invasive cancer. The average time from positive FOBT to colonoscopy was 269 days (SD 158 days). In each category, the time to colonoscopy was: 253 days (SD 160) for no adenomas; 283 days (SD 153) for adenomas; 295 days (SD 167) for advanced adenomas; and 265 days (SD 153) for invasive cancer. Only 5 of the subjects (2.0%) completed the colonoscopies within the recommend time interval of < 60 days and of these, 2 were without polyps, 2 had adenomatous polyps, and 1 subject had invasive cancer.
In this single center review, the average time from positive FOBT to colonoscopy was well above the new directive. It remains unclear what effect this delay has on the quality of colorectal cancer care.
Adherence to the new VA directive will require a significant change in practice. Further investigation into the relationship between delay to colonoscopy and colorectal cancer outcome is imperative to ensure that guidelines are consistent with scientific evidence.