The oncologic removal of the rectum often requires both an abdominal and a perineal approach. During the abdominal portion of the procedure, the superior rectal vessels are controlled, the rectum and mesorectum dissected, and colostomy created. During the perineal portion, the rectum and anus are detached from the ischiorectal fat, the levator muscles, and whatever portion (if any) of the distal portion of the genitourinary organs not planned for removal. The boundary between the abdominal and perineal parts of the procedure is delineated by the levator muscles. The abdominoperineal excision (APE) of the rectum is now much safer than when it was first introduced more than a century ago. However, despite the advances in surgical technique and perioperative care, it remains a surgical challenge due to the complex anatomy of the pelvis.
For many years after its original description, the APE was the only surgical option for patients with rectal cancer. As a result of advances in the understanding of the dissemination of rectal cancer, along with improvements in surgical technique and instrumentation, and the use of neoadjuvant therapy, most rectal cancers are now treated with sphincter-saving procedures (SSPs). APE has been relegated to the treatment of very distal rectal cancers involving the sphincter complex or the levator muscles. Therefore, the division of the levators muscles is a critical step of the operation that determines the oncologic outcomes.
Almost immediately following the initial description of APE, surgeons began introducing minor modifications to the procedure. The number of options has recently expanded with the introduction of minimally invasive techniques. The abdominal part of the operation can be performed as an open, laparoscopic, or robotic procedure; the perineal part can be performed with the patient in lithotomy or in the prone position. In any case, successful APE requires perfect knowledge of the anatomy of the abdomen, pelvis, and ischiorectal fossa, as well as adherence to a few sound surgical principles. The APE operation is very similar to the pelvic exenteration with perineal phase, which is described in Chapter 8. The current chapter will specifically focus on the APE for distal rectal cancers.
BACKGROUND AND HISTORICAL PERSPECTIVE
Surgical treatment of rectal tumors did not become feasibleuntil the introduction of the colostomy by the French surgeon, Jean Amussat, during the Napoleonic wars. Distal proctectomy through the perineum, which reaches within a few centimeters of the promontory, was already being performed by Lisfranc and others in the 1830s. However, it was not until the late nineteenth century that surgeons really began to regularly perform this operation.1
The perineal excision of the rectum was performed in 2 stages. The first stage consisted of a minilaparotomy to inspect the peritoneal cavity for signs of tumor dissemination, and to create a loop or double-barrel colostomy. In the second stage, performed several days later, the surgeon removed the anus, the ischiorectal ...