Neuroanatomy of the Minor Pelvis-Significant Area in the Surgery of Rectal Carcinoma

Abstract

For centuries, there are attempts to develop a strategy of appropriate rectal carcinoma management. However, surgery remains the essential element of therapy, being proposed by Morgagni in the eighteenth century. The anterior rectal resection method established by Dixon, in addition to Total Mesorectal Excision (TME), supplemented by combined therapy (radiotherapy, chemotherapy) initiated modern rectal carcinoma management techniques, aimed at oncological radicalism with sphincter preservation (Sphincter Saving Procedure – SSP, Sphincter Sparing Surgery – SSS, Sphincter Preserving Surgery – SPS) (1). Surgical intervention is considered as the standard oncological therapeutic method in case of rectal carcinoma patients, supplemented by combined therapy (radiotherapy, chemotherapy), depending on the stage of the disease and biology of the tumor. Surgery consists in the excision of the rectum and tumor (maintained margins free of neoplastic infiltration – R0 resection), as well as mesorectum with its vessels and lymph nodes. In case of tumors localized in the upper part of the rectum, tumor specific mesorectal resection (TSME) is preferred (2). In case of tumors localized in the medial and inferior part of the rectum low anterior resections are performed, in addition to total mesorectal excisions. Intestinal continuity is restored after the anastomosis of the proximal intestinal segment with a fragment of the rectal ampulla or at the level of the anal canal (coloanal anastomosis) (3). The technique proposed by Heald and Enker consisting in the excision of the mesorectum should always be respected, enabling to maintain the undamaged mesorectal (oncological radicalism) and Tolt’s fascia (NerveSparing Technique). Depending on the localization of the tumor rectal sphincters are preserved, and intestinal continuity is restored after the anastomosis of bowel segments free of neoplastic infiltration with all preserved techniques of anastomosis surgery (4). In most cases the reservoir part of the rectum is lost (different fragments of the rectal ampulla are preserved). Intestinal continuity restoration consisting in the simple anastomosis of the colon and rectal stump, and the creation of the neorectum cistern (by means of transverse coloplasty or other intestinal cisterns) do not guarantee normal functioning of the anorectum. Dixon’s (promoter of the anterior resection) suggestion that the procedure had no influence on the functioning of the sphincters proved to be erroneous (5). Combined oncological therapy of rectal carcinoma also exerts a negative effect on the genitourinary system. Urinary bladder and urethral sphincter dysfunction (urine retention and incontinence), as well as sexual disturbances both in male and female patients (impotence, lack of ejaculation, retrograde ejaculation, lack of orgasm) can result from the operation, especially in case of lower rectal carcinomas. The percentage of the above-mentioned postoperative complications ranges between 10 and 60% (6). The described disturbances result from damage to the autonomic innervation of the mentioned organs. The wide range of the above-mentioned disturbances depends on the experience of the surgeon, thus, being dependent of the learning