Factors associated with sphincter-preserving surgery for rectal cancer at national comprehensive cancer network centers

Objective: To determine rate and predictors of sphincter-preserving surgery (SPS) for rectal cancer patients treated at specialty institutions. Sum ary Background Data: SPS has been considered a surrogate for surgical quality, and sphincter preservation is tremendously important to patients. Evidence of association between case volume and SPS rate has prompted recommendations that all rectal cancer patients undergo surgery at specialty institutions. However, rates of SPS, and the factors associated with ability to perform SPS, have not been well-characterized. Methods: A prospective registry of all colorectal cancer patients treated at 7 National Comprehensive Cancer Network institutions was used to identify patients with clinical stage I-III rectal cancer undergoing surgery (n = 674) between September 2005 and October 2007. Patient, tumor and treatment factors were abstracted; patients' clinical characteristics with and without SPS were compared using descriptive statistics and multivariable logistic regression. Results: Of 674 identified patients (median age, 58.2; 60% male), 520 (77%) had SPS. Of these, 240 had low anterior resection with coloanal anastomosis, 268 low anterior resection without coloanal anastomosis; 12 had other SPS procedures. Sixty-two percent had a temporary diverting stoma. On multivariable analyses, independent predictors of SPS included younger age at diagnosis, proximal location in the rectum, nonfixed tumor, and institution. Conclusions: SPS rates at National Comprehensive Cancer Network institutions exceed those seen in population-based samples and clinical trials. In addition to expected variation in SPS rates based on patient and tumor characteristics, we identified variation among institutions. Although the optimal rate of SPS remains unknown, this provides areas for further research and potential performance improvement.