Effects of neoadjuvant chemoradiotherapy on anorectal function in patients with mid and low rectal cancer

Abstract

To evaluate the effects of neoadjuvant chemoradiotherapy on anorectal function in patients with mid and low rectal cancer. A total of 22 patients with mid and low rectal cancer were enrolled into this study from October 2012 to November 2013. There were 14 males and 8 females with a mean age of (59 ± 10) years. We collected the defecation-related symptoms with questionnaire interview and evaluated the anorectal function with three-dimensional high-resolution manometry before neoadjuvant chemoradiotherapy and at 6 weeks after radiotherapy. The defecation-related symptoms (including increase in stool frequency, change in stool form, hematochezia and urgency, etc.) improved significantly after neoadjuvant chemoradiotherapy (n = 21). Among those with lower rectal cancer (n = 8), the length of high-pressure zone in manometry increased significantly after neoadjuvant chemoradiotherapy ((3.84 ± 0.61) vs (2.96 ± 0.80) cm, P = 0.003). However, there was no significant change for other parameters in anorectal function (all P > 0.05). In patients with mid and low rectal cancer, neoadjuvant chemoradiotherapy may improve the defecation symptoms and enhance anal sphincter high-pressure zone for lower rectal cancer. And it is probably due to its tumor-downsizing effect.