Laparoscopic Abdominoperineal Resection

Abstract

A rectal cancer located within the narrow confines of the bony pelvis has for centuries been the bugbear of abdominal surgeons. Advances in operative technique, surgical technology, imaging methods, and multimodal therapies have dramatically improved the prospects of this once fatal disease. Despite the considerable progress, cancer of the rectum remains one of the most challenging conditions encountered by colorectal surgeons in present times.

Introduction

A rectal cancer located within the narrow confines of the bony pelvis has for centuries been the bugbear of abdominal surgeons. Advances in operative technique, surgical technology, imaging methods, and multimodal therapies have dramatically improved the prospects of this once fatal disease. Despite the considerable progress, cancer of the rectum remains one of the most challenging conditions encountered by colorectal surgeons in present times.

Perhaps the most notable contribution of the twentieth century to the management of rectal cancer was that by Sir William Ernest Miles, who described abdominoperineal excision of the rectum and anal sphincter complex with a permanent colostomy in 1908 [1]. His groundbreaking notion of reducing recurrence by removing as much lymphatic drainage of the rectum as possible in a “cylindrical” concept formed the basis of modern rectal cancer surgery [2]. Miles’ revolutionary work is still the topic of vivid discussion more than 100 years later [3, 4]. For decades, abdominoperineal resection (APR) was the standard treatment for all rectal cancers, until anterior resection with a colorectal anastomosis was reported (in 1948) to be a safe and acceptable surgical therapy for lesions located in the upper half of the rectum [5]. From the late 60s to the early 70s, introduction of a transrectal circular stapling device [6], as well as the coloanal handsewn anastomotic technique [7] enabled surgeons to perform progressively more distal rectal resections while preserving the anal sphincter. In 1982, Bill Heald identified the “Holy Plane” of dissection between the mesorectal and presacral fascia for total mesorectal excision (TME) [8], which became the gold standard for oncologic resection of middle to low rectal cancers.

Still, it was recognized that TME alone provided insufficient local control for more advanced disease. A major milestone came in the form of combined chemoradiotherapy prior to surgery [9]. For the past 20 years, neoadjuvant chemoradiation therapy (NACRT) has been advocated for locally advanced, i.e., stage 2 and 3 cancers located in the mid to distal rectum, prior to surgical resection, followed by adjuvant chemotherapy for nodepositive disease. 50–60% of patients are downstaged after NACRT, with approximately one-fifth showing a pathologic complete response [10]. This approach, along with enhanced surgical techniques, has reduced the local recurrence rate to 5–10% at 5 years. Next, the focus turned to improving systemic control [11]. Total neoadjuvant therapy, which provides all necessary chemotherapy and radiation prior to surgery, aims to deal with circulating micrometastases earlier for better systemic control and is now recognized as a valid treatment option for locally advanced tumors [10, 12].

With increasing acknowledgment of the effectiveness of adjunctive therapies, Habr-Gama and colleagues in the mid-2000s pioneered the “watch-and-wait” approach on the basis of an observed 26–27% rectal cancer pathological response rate to NACRT [13]. Organ preservation (of the rectum) thus emerged as a possible nonsurgical option in the management of rectal cancer [14]. A 2018 meta-analysis of 13 cohorts showed a complete clinical response rate of 22.4% with a 3 year cumulative local recurrence risk of 21.6%. Most of these patients underwent salvage surgery with a 79.1% R0 resection rate, 45.3% sphincter preservation rate, and 3-year overall survival and disease-free survival of 93.5 and 89.2%, respectively [15]. No randomized trial exists and substantial deficiencies in our knowledge of the organ-preserving approach prevent it from becoming mainstream therapy. Nonetheless, current evidence suggests that the watch-and-wait may be reasonable for selected, including high surgical risk patients, with locoregionally advanced mid to distal rectal cancers who demonstrate complete clinical response [11].

Surgical technique for rectal cancer has come a long way since Miles’ seminal paper. The laparoscopic approach to APR has been proven to reduce postoperative complications and hasten recovery, without compromising oncologic outcomes, recurrence rates, and survival [16]. Moreover, the advantages of laparoscopic APR over open surgery are more pronounced than that of anterior resection as only small port scars remain without the need for abdominal specimen extraction. Robotic surgery and transanal total mesorectal excision are two newer methods that have been the focus of both retrospective research and prospective trials in recent years. A 2019 meta-analysis by Simillis et al. involving 6237 patients from 29 randomized trials compared the classic open versus laparoscopic versus robotic versus transanal TME; all methods appeared to have comparable morbidity rates and long-term outcomes. However, the laparoscopic and robotic methods appeared to improve postoperative recovery and the open and transanal approaches seemed to benefit oncologic resection [17].

Enhanced surgical techniques in the setting of effective multimodal adjunctive therapies for low rectal cancers have decreased the rates of APR. A pooled analysis of five large European trials suggests that the APR procedure itself was a predictor of increased local recurrence and death [18]. Compared to anterior resection, patients who undergo APR also report worse body image and sexual enjoyment at 1 year postsurgery [19]. Nonetheless, APR is still the requisite procedure in many circumstances and remains an essential component of the armamentarium of colorectal surgeons today. In this chapter, we will examine the use of the laparoscopic APR technique for low rectal cancer.

Indications

An individualized approach is mandatory in the management of patients with distal rectal cancer. Accurate systemic staging along with a dedicated multidisciplinary team discussion should be conducted as per existing clinical guidelines [10, 20]. The following should be considered when establishing the optimal surgical approach for each patient:

Tumor Characteristics

Location of the tumor and involvement of the anal sphincters can be determined by a digital rectal examination. Fixed tumors with sphincter or levator muscle invasion will necessitate an APR. Involvement of the prostate or anterior wall of the vagina may require pelvic exenteration. Magnetic resonance imaging (MRI) of the pelvis using a specific rectal cancer protocol is the modality of choice for locoregional staging. The MERCURY trial showed that MRI can predict surgical resectability, overall survival, and local recurrence through assessment of the MRI tumor regression grade [21]. The utility of endorectal ultrasound is limited to the differentiation of T1 and T2 tumors, the former of which may be amenable to local excisional procedures in the absence of high-risk MRI features. Locally advanced low rectal cancers should be referred for neoadjuvant radiation. We use a long course protocol of 45–50.4 Gy in 25–28 doses given in conjunction with chemotherapy, typically 5-FU. Surgery may be performed between 5 and 12 weeks following full dose 5.5 weeks NACRT [10], although the ideal timing remains the subject of controversy [20]. Posttreatment MRI is important to assess response and can be performed at the mid-way point between the end of treatment and intended timing of surgical resection.

Sphincter preservation may become possible in cases where initial tumor bulk prevented consideration of such surgery and the extent of the tumor is improved after neoadjuvant therapy. An APR is indicated where an R0 resection of the tumor would result in loss of anal sphincter function and incontinence [10]. The acceptable distal resection margin for low rectal cancers should be greater than 1 cm, although a < 1 cm margin has been shown not to compromise oncologic safety in selected patients [22]. Intersphincteric resection for very low locally advanced rectal cancer has also been found to have acceptable oncologic outcomes [23].

Sphincter Function

A thorough history and physical examination can determine the pretreatment baseline function. It would be pointless exercise to preserve a poorly functioning anal sphincter. A meta-analysis of 25 studies with 6548 patients demonstrated that NACRT negatively affected long-term anorectal function after surgery [24]. It is therefore advisable to repeat functional assessment following neoadjuvant therapy. If available, objective measurement using anal manometric studies can be performed. For borderline cases, it is important to consider the high prevalence (of approximately 40%) and long-term persistence of bowel dysfunction, the so-called low anterior resection syndrome (LARS), following sphincter-sparing rectal surgery [25,26,27]. Patients with severe LARS symptoms may prefer a permanent stoma and would have benefited from an upfront APR. This possibility should be emphasized preoperatively to patients who are at higher risk for LARS, including those with a history of radiotherapy or in whom anterior resection would result in a low anastomotic height [26]. Overall functional status should also be taken into account.

Preoperative Preparation

Ostomy nurse counseling and stoma site selection for optimal positioning of the permanent colostomy are important to facilitate postoperative stoma care and function. The patient should be enrolled in an enhanced recovery after surgery (ERAS) program. We do not advocate mechanical bowel preparation before APR. Prophylactic intravenous antibiotics are given at anesthetic induction and throughout the duration of surgery. Pharmacological or mechanical venous thromboembolism prophylaxis should be instituted due to the high-risk nature of this surgery. The ureters can be stented prior to rectal resection to facilitate intraoperative identification, which may be advantageous in difficult cases with previous pelvic surgery. A urinary catheter must be inserted.

OT Setup

Abdominal Phase

Our patient position prior to draping can be seen in Fig. 1. The patient is placed in the modified Lloyd-Davis position with the lower limbs in foot stirrups and the buttocks a few centimeters off the caudal edge of the operating table. Both arms are tucked in to facilitate positioning of the surgeon, camera operator, and assistant. A small sandbag (or folded drapes) is placed below the sacrum to elevate the pelvis, enabling better visualization of the deep pelvic structures during surgery. A steep Trendelenburg position is maintained for most of the abdominal phase. To stabilize the patient’s position, we use fixed shoulder supports to absorb the patient’s weight, with soft gel pads minimizing the risk of pressure injury. To provide additional support, a strip of strong adhesive tape is used to strap the patient’s chest, just above the nipple line, to the sides of the table. Alternatively, an adjustable “bean bag” above a soft gel layer can be molded around the patient to prevent sliding. We use a soft elastic bandage, wrapped tightly around the lower limb, as a substitute for compression stockings. The lower limbs should be in a relaxed posture with the knees flexed at 45° to prevent overstretching of the peripheral nerves (Fig. 2).

Fig. 1

APR abdominal phase standard positioning before draping

Fig. 2

The ideal position of the lower limbs during surgery

Operating setup and ports are shown in Fig. 3. A 12 mm camera trocar is placed via an umbilical incision under direct vision. Working trocars consist of a 12 mm trocar placed two fingerbreadths medial to the right anterior superior iliac spine and a 5 mm trocar midway between the right iliac fossa trocar and the umbilical trocar. In our experience, this port position provides the best ergonomics for deep pelvic dissection. The assistant ports are a right-to-left mirror image of the working ports, using two 5 mm trocars. One assistant trocar can be placed at the intended (and preoperatively marked) colostomy site to minimize operative incisions. A single assistant trocar may be sufficient in straightforward cases.

Fig. 3

(Above) Schematic of operating setup and port placement for laparoscopic APR. (Below) Left-sided assistant trocar can be placed at the intended end colostomy site

Perineal Phase

Upon completion of the abdominal phase, the patient is transferred to a trolley and the operating table is prepared for the prone jackknife (Kraske) position as shown in Fig. 4. The leg boards are reattached. A donut head pad is used for facial support. It is necessary to provide adequate padding for the colostomy and drain site while the patient is prone to prevent pressure injury. The knees are kept in slight flexion on a separate cushioned cardiac trolley (Fig. 5), to prevent stretch of the lower limb nerves.

Fig. 4

Preparing the operating table for the prone jackknife position

Fig. 5

The prone jackknife position for the APR perineal phase

Adhesive tape is used to splay the buttocks apart and anchored to the table frame on each side (Fig. 6). The anus is sutured shut to prevent leakage of stool during the procedure. For the perineal skin incision, the posterior extent should be midway between the tip of the coccyx and the anus, the anterior extent at the perineal body, and the lateral extent midway between the ischial tuberosities and the anus. Operative landmarks as well as the elliptical skin incision are shown in Fig. 6.

Fig. 6

Preparing the perineum for the perineal phase. The downward arrow marks the coccygeal location and the points on either side of the anus indicate the position of the ischial tuberosities. Using these landmarks, the skin incision is delineated as shown

Surgical Technique

Abdominal Phase Essential Steps

• 1. Medial to lateral colonic mobilization

• 2. Inferior mesenteric artery ligation

• 3. Rectal mobilization pelvic floor

• 4. Proximal bowel transection

• 5. End colostomy creation

Abdominal Phase Technique

The initial approach to the APR abdominal phase is not unlike that for a low anterior resection (see chapter on Anterior Resection). A splenic flexure takedown is unnecessary, and the proximal colon is mobilized just enough to allow the exteriorization of an end colostomy following bowel resection. TME dissection and rectal mobilization should be progressed as distally as possible to facilitate the subsequent perineal phase. A cotton tape tie at rectosigmoid junction is useful to provide traction of the rectum out of the pelvis (Fig. 7). The knot is grasped by the surgical assistant for retraction and manipulation of the rectum during TME. For females, the uterus can be temporarily hitched to the anterior abdominal wall using a Prolene 2–0 straight needle passed through the uterine fundus or the broad ligaments (Fig. 8). This provides visualization without the need for traction by the assistant. Following adequate colon and rectal mobilization, the proximal colon is transected with an appropriate oncologic margin using an endoscopic linear stapler. A drain is placed in the pelvis prior to closure. The sigmoid colon is exteriorized via a left-sided skin incision and the abdominal wounds are closed before the end colostomy is matured.

Fig. 7

(Above) A cotton tape is tied around the upper rectum. (Below) The knot is grasped by the surgical assistant for retraction and manipulation of the rectum

Fig. 8

(Above) A straight needle is passed from the skin through the fundus of the uterus. (Below) The uterus is hitched to the anterior abdominal wall to provide better access to the deep pelvis

Perineal Phase Essential Steps

• 1. Extra-sphincteric incision

• 2. Entry into abdominal cavity via anococcygeal ligament

• 3. Division of lateral levator attachments

• 4. Exteriorization of proximal end of the specimen

• 5. Division of the anterior attachments (to the prostate/vagina)

• 6. Wound closure (with mesh or flap reconstruction if necessary)

Perineal Phase Technique

A 2018 meta-analysis of 1663 patients found that the prone approach for APR is associated with decreased blood loss and operative time, with no differences in the incidence of postoperative wound infection or intraoperative rectal perforation (IOP). Positioning also did not affect circumferential resection margin (CRM) positivity or local recurrence rates [28]. We favor a prone position for APR for anteriorly based tumors for the superior visualization of the anterior plane between the tumor and the prostate or vagina. For cases in which the dissection is potentially difficult due to anatomical constraints, bulky tumors, or previous radiation, the lithotomy position allows a combined abdominal and perineal approach which may be useful to establish an accurate plane of dissection, although pneumoperitoneum will be lost once the abdominal cavity is entered from below.

The objective of the perineal phase of an APR for low rectal cancer is to excise the anal canal with a wide margin. The initial elliptical incision is deepened past the ischiorectal fat circumferentially until the levator muscles are encountered. The optimal location for entry into the abdominal cavity is through the anococcygeal ligament posteriorly (Fig. 9). The coccyx can be excised to facilitate entry or a margin-negative resection [4]. The St. Marks perineal retractor or the Lone Star retractor may also be used during the perineal phase of surgery.

Fig. 9

Traction on the anus with the arrow showing the position of the coccyx

In a conventional APR (CAPR), the lateral attachments of the levators to the distal rectum/upper anal sphincter are divided close to the bowel. This type of dissection frequently produces a “waisted” specimen where the abdominal and perineal dissections meet. This was reported to increase the rate of IOP, CRM positivity, and local recurrence. The extralevator abdominoperineal excision (ELAPE) approach, described by Holm et al. in 2007 [29], produces a more “cylindrical” specimen by avoidance of dissection of the mesorectum off the levators during the abdominal phase and complete (wide) excision of the levators during a prone perineal phase. A recent meta-analysis shows that ELAPE reduces IOP and local recurrence rates, without increasing perineal wound complication rates, when compared with CAPR [30]. The RELAPe randomized trial also showed no difference in complications with ELAPE, and in addition found a statistically significant reduction in CRM positivity rates, compared to non-ELAPE [31]. We recommend the extralevator approach for locally advanced tumors involving the levators or external sphincters and tumors with a threatened CRM following NACRT.

Following division of the posterior and lateral attachments, the proximal end of the specimen can be exteriorized (Fig. 10). A method to facilitate the proximal exteriorization is to suture a gauze to the staple line during the abdominal phase; the gauze is then inserted into the presacral space and can be easily identified upon entry into the abdominal cavity during the perineal phase. With the proximal and distal ends of the bowel already mobilized, the specimen can be dissected off the prostate or vagina anteriorly. The ideal APR specimen should have an intact mesorectum without “waisting” (Fig. 11). The wound is cleansed thoroughly before the transabdominal drain is located and appropriately positioned within the pelvis prior to closure (Fig. 12).

Fig. 10

Traction on the mobilized anus and exteriorization of the proximal end of the specimen

Fig. 11

APR specimen

Fig. 12

The perineal wound is closed over the drain in the pelvis

The perineal wound can be closed primarily or using a mesh or flap. If a mesh is used, the edges are sutured to the insertions of the excised levator muscles to close the tissue defect at the level of the pelvic floor, providing support and theoretically reducing the risk of perineal herniation. Biologic mesh is preferred over synthetic due to reduced adhesions with small bowel, as well as the better infection risk profile in a contaminated field.

The 2017 Association of Coloproctology of Great Britain and Ireland (ACPGBI) Position Statement on the closure of the perineal defect after APR for rectal cancer makes the following relevant recommendations/findings [32]:

• Primary closure of the perineum can be used following CAPR (strong recommendation)

• Mesh closure has rarely been used for perineal wound closure following CAPR (moderate quality evidence)

• When concerns regarding perineal wound healing exists, myocutaneous flap closure may be considered as an alternative method (weak recommendation)

• Primary perineal wound closure following ELAPE has been reported and appears to be feasible (weak evidence)

• Biologic mesh has been used to reconstruct the perineal defect after ELAPE (moderate quality evidence)

• Perineal wound complications are significantly increased when neoadjuvant radiotherapy is delivered, regardless of whether CAPR or ELAPE is performed (moderate quality evidence)

• There is insufficient evidence to recommend one particular method of perineal closure over another following neoadjuvant radiotherapy

• There is insufficient evidence to support a particular method of perineal wound closure following laparoscopic approach to APR

In a CAPR, the remnant levator muscles should be used to reconstruct the perineal defect. The subcutaneous tissue is then approximated in multiple layers. A subcutaneous drain may reduce the risk of infection (Fig. 13).

Fig. 13

Closure of the perineal wound using interrupted mattress suture and a subcutaneous drain

Complications and Management

During deep pelvic surgery, injury to the ureters, prostate, seminal vesicles, vagina, autonomic nerves, sacral venous plexus, and internal iliac vessels can occur. Membranous urethral injury is a risk during the anterior portion of the perineal dissection; this risk can be possibly reduced with prone positioning and exteriorization of the proximal end of the specimen after distal, posterior, and lateral mobilization as previously described.

While current evidence is inconclusive, ELAPE surgery is theoretically at higher risk for perineal wound complications due to the larger perineal defect and lack of muscle closure. A 2014 meta-analysis of 32 studies reported that the pooled percentage of perineal wound complications in patients who did not undergo neoadjuvant radiotherapy was 15.3% after CAPR versus 14.8% after ELAPE. After neoadjuvant radiotherapy, perineal wound problems occurred in 30.2% of CAPR versus 37.6% following ELAPE [33]. Data from the 2015 English Low Rectal Cancer Abdominoperineal Excision (LOREC APE) registry recorded overall perineal complications in 21% of patients, with the majority being infective [34]. Infective complications include cellulitis, abscess formation, wound dehiscence, and chronic sinus formation. Avoiding fecal contamination, meticulous hemostasis, and closed-suction drainage of the pelvis can reduce infective complications.

Perineal herniation, defined as a palpable perineal bulge on standing or straining, is a possible complication following APR. Following primary wound closure, the pooled incidence of perineal hernias was 1.8% and 2.0% after CAPR and ELAPE, respectively [33]. Surprisingly, perineal hernias after biological mesh closure following ELAPE had a meta-analysis pooled incidence of 8.2%, which the authors suggested may be a result of a learning curve issue or a longer follow-up period for mesh studies [33]. Omentoplasty is the transposition of a pedicled omental flap, which can be used to fill the presacral space or sutured to the pelvic inlet during the abdominal phase. There is some evidence showing that omentoplasty, in conjunction with primary closure or a biological mesh, may reduce wound-related complications and herniation, by occupying the pelvic dead space rather than fluid or small bowel [35]. This technique is limited by the amount of omentum available. Repair of a perineal hernia may be difficult and generally involves the use of a combined abdominal and perineal approach with mesh or flap reconstruction of the pelvic floor.

Postoperative Care

The postoperative management of APR patients follows that of colorectal enhanced recovery protocols. In our experience, no particular posture is necessary to facilitate healing but the patient is advised to avoid squatting for 3 weeks as this position may increase tension on the perineal wound closure. The perineal wound must be examined for possible complications prior to discharge.