The Influence of Neoadjuvant Chemoradiation for Middle and Lower Rectal Cancer on Anorectal Function.

Abstract

To date, there is no clear understanding whether preoperative long-course chemoradiotherapy combined with surgery for rectal cancer is detrimental to anorectal function. The purpose of this study was to clarify the influence of preoperative chemoradiotherapy and surgery for middle and lower rectal cancer on postoperative anorectal function. Data of 113 patients with middle or lower rectal cancer treated with preoperative chemoradiotherapy plus surgery or surgery alone between January 2013 and December 2016 were analyzed. A total of 84 and 29 patients underwent low anterior resection and intersphincteric resection, respectively. In patients with T3 or deeper and with any N stage cancer below peritoneal reflection, surgery plus lateral lymph node dissection or preoperative radiation (total: 50.4 Gy/28 fractions) to the pelvis with chemoradiotherapy plus surgery was treated. Anorectal function was assessed prior to treatment and 6 and 12 months postoperatively. Specifically, maximum resting pressure and maximum squeezing pressures were measured. The Wexner score was recorded prior to treatment and 12 months postoperatively. maximum resting pressure and maximum squeezing pressure decreased post-surgery in both groups. Maximum resting pressure and maximum squeezing pressure at 12 months and the Wexner score at 12 months post-surgery were comparable among patients treated with chemoradiotherapy plus surgery and those treated with surgery alone. Preoperative chemoradiotherapy did not clearly impair postoperative anorectal function in patients who underwent low anterior resection and intersphincteric resection.