Clinical parameters predictive for sphincter-preserving surgery and prognostic outcome in patients with locally advanced low rectal cancer.

BACKGROUND: Although controversial, there are data suggesting that clinical parameters can predict the probability of sphincter preserving procedures in rectal cancer. The purpose of this study was to investigate the association between clinical parameters and the sphincter-preserving surgery rate in patients who had undergone neoadjuvant combination therapy for advanced low rectal cancer. METHODS: In this single center study, the charts of 540 patients with locally advanced rectal cancer who had been treated with induction chemotherapy-and/or neoadjuvant concomitant radiochemotherapy (nRCT) over an 11-year period were reviewed in order to identify patients with rectal cancer ≤6 cm from the anal verge, who had received the prescribed nRCT only. Univariate and multivariate analyses were used to identify pretreatment patient- and tumor associated parameters correlating with sphincter preservation. Survival rates were calculated using Kaplan-Meier analyses. RESULTS: Two hundred eighty of the 540 patients met the selection criteria. Of the 280 patients included in the study, 158 (56.4%) underwent sphincter-preserving surgery. One hundred sixty-four of 280 patients (58.6%) had a downsizing of the primary tumor (ypT < cT) and 39 (23.8%) of these showed a complete histopathological response (ypT0 ypN0). In univariate analysis, age prior to treatment, Karnofsky performance status, clinical T-size, relative lymphocyte value, CRP value, and interval between nRCT and surgery, were significantly associated with sphincter-preserving surgery. In multivariate analysis, age (hazard ratio (HR) = 1.05, CI95%: 1.02-1.09, p = 0.003), relative lymphocyte value (HR = 0.94, CI95%: 0.89-0.99, p = 0.029), and interval between nRCT and surgery (HR = 2.39, CI95%: 1.17-4.88, p = 0.016) remained as independent predictive parameters. CONCLUSIONS: These clinical parameters can be considered in the prognostication of sphincter-preserving surgery in case of low rectal adenocarcinoma. More future research is required in this area.