Not only hysterectomy but also cesarean section can predict incomplete flexible sigmoidoscopy among patients with prior abdominal or pelvic surgery.

BACKGROUND Flexible sigmoidoscopy (FS) is a safe and effective method for colorectal cancer (CRC) screening. Several studies have demonstrated that individuals who have undergone surgery are at a greater risk of having incomplete FS. This study explored predictors of incomplete FS and reduced polyp detection rates for participants who had undergone abdominal or pelvic surgery. METHODS From January 2009 to December 2009, individuals participating in health examinations and who had undergone abdominal or pelvic surgery were invited to participate in this investigation. Four experienced gastroenterologists performed examinations using a 60-cm Olympus video sigmoidoscope. Factors associated with incomplete FS insertions and reduced polyp detection rates were analyzed using logistic regression models. RESULTS Overall, 106 eligible individuals were analyzed, and 45 (42%) incomplete FS insertions were reviewed. Fifty participants (47%) had undergone pelvic surgery, and the other 56 (53%) had undergone abdominal surgery. Pelvic surgeries were cesarean section (25%) and hysterectomy (15%); appendectomy (36%) was the most common abdominal surgery. The main pathological FS findings were hemorrhoids (54%) and adenomatous polyps (18%). Multivariate analysis indicated that only prior pelvic surgery [odds ratio (OR), 3.54; p = 0.01] was an independent risk factor for incomplete FS insertion. Incomplete examinations were inversely related to adenomatous polyp detection rates (OR, 0.23; p = 0.03). CONCLUSION Prior pelvic surgery, particularly cesarean section and hysterectomy, is an independent factor for incomplete FS insertion in a selected adult population. In addition, incomplete FS can increase the risk of missing polyps, particularly in individuals who underwent pelvic surgery.