Rectal Cancer: Function-preserving Surgery

Kim, Nam Kyu

Abstract

The main goals in the surgical treatment of rectal cancer are to remove the cancer completely and to preserve the anorectal function. Rectal cancer is one of the leading health issues in Korea because of its increasing incidence with changing lifestyles and diets. The optimal treatment of rectal cancer is based on a multimodality approach. Among the modalities, proper surgery is the key for a curative treatment. In the early 20th century, local recurrence was reported to be as high as 30~40%. However, after the introduction of total mesorectal excision (TME), local recurrence decreased dramatically (to less than 10%). TME includes on sharp pelvic mesorectal dissection and complete clearing of the rectal cancer and the mesorectum along the rectal proper fascia. TME is now considered as a standard procedure for surgical treatment of rectal cancer. These days, sphincter-saving surgical techniques, such as transanal excision, ultralow anterior resection with coloanal anastomosis, and intersphincteric resection, have become popular for the treatment of low rectal cancer. Many researchers reported that oncologic outcomes were not compromised by the increased sphincter preservation rate. In clinical settings, the quality of life should be considered important because of the improved oncologic results in recent years. Surgeon should be aware of changes in the anorectal function after surgery. Reservoir and fecal continence, as well as sexual and voiding functions, should be closely evaluated during follow-up period. Impaired anorectal function may have multiple contributing factors: for example, a reduced reservoir volume, an unnoticed complex injury of the anal sphincter, or a traction injury (anal dilation). In terms of poor sexual and voiding functions, identification of the autonomic nerve plexus in the operative field is not enough for preserving the sexual and voiding functions. During pelvic dissection, traction injury caused by blunt dissection and electrothermal or vasa nervosum injury during sharp perimesorectal dissection should be avoided for better functional results. Preoperative or postoperative radiation may also be a reason for sexual and voiding dysfunction. If the ultimate goal of rectal cancer surgery is to be achieved, precise surgical technique and proper patient selection are mandatory. This issue contains recent advances in sphincter-saving surgery and nerve preservation for rectal cancer, which will be a useful reference for colorectal surgeons.