The impact of body mass index and nuclear β-catenin on survival in locally advanced rectal cancer treated with preoperative radiochemotherapy

BACKGROUND AND OBJECTIVE We examined the prognostic value of obesity and nuclear β-catenin in patients with locally advanced rectal cancer. METHODS We prospectively recruited a total of 98 eligible patients with locally advanced cancer for preoperative radiochemotherapy followed by total mesorectal excision. Patients' height and weight were reaorded before radiochemotherapy, and the immunohistochemical expression of nuclear β-catenin was analyzed. Disease-free survival (DFS) was analyzed using the Kaplan-Meier method and a Cox regression model was employed for the multivariate analysis. RESULTS Obese patients were associated with a lower number of recurrences (3.6% vs. 34.3%, P = 0.001), and a higher DFS (95% vs. 53%; HR, 0.09; 95%CI, 0.01-0.64; P = 0.005) than non-obese patients. In the multivariate analysis, body mass index, nuclear β-catenin expression, and the absence of lymph node metastases showed a significant increase in DFS. CONCLUSIONS Obesity and nuclear β-catenin are independent favorable prognostic factors for DFS in locally advanced cancer treated with preoperative radiochemotherapy. J. Surg. Oncol. 2017;115:301-306. © 2017 Wiley Periodicals, Inc.