Neoadjuvant chemoradiotherapy in rectal cancer and anorectal sphincter dysfunction: Review of the literature.

The purpose of this article was to review the current medical literature regarding deterioration of anorectal function in patients receiving neoadjuvant chemoradiotherapy before surgery for locally advanced rectal cancer. We reviewed the current literature including research studies, electronic database PUBMED-MEDLINE, published research results and metanalysis papers from high-volume institutes, collecting and comparing the different results. Pathophysiology as well as emerging solutions for treating anorectal sphincter dysfunction were researched in order to provide an insight of this complex issue. All available data suggest that neoadjuvant radiation therapy impairs internal anal sphincter function mostly through nerve damaging mechanisms, as nerves are more susceptible to damage than muscular fibers. Current radiotherapy recommendations are oriented in exclusion of anal canal from radiation field when oncologically safe or using new sphincter-sparing techniques for neoadjuvant radiotherapy aiming to improve the patient quality of life receiving radiation therapy prior to surgery. However, more well designed studies are required to assess the pathophysiology as well as treatment options for this complex matter, which strongly affects the quality of life of rectal cancer patients.