EP367 - A Perineal-First Approach Extralevator Abdominoperineal Excision with Myocutaneous Gracilis Flap Reconstruction for Locally-Advanced Rectal Cancer

Purpose/Background: Extralevator abdominoperineal excision (ELAPE) emphasizes the en bloc removal of the levator to produce a cylindrical specimen with better clearance. Dissection beyond the “conventional” planes aims to lower the risk of CRM positivity and intraoperative specimen perforation. An approach that provides adequate exposure and offers additional working space—such as prone for low rectal tumors--is essential to achieving better specimen quality and optimal surgical outcomes.

Methods/Interventions: An elderly female presented with an obstructing locally-advanced rectal cancer extending beyond the perianal region. (Fig. 1A) She complained of frequent soiling and hematochezia. Pelvic MRI revealed a 13.5 x 4.5 x 7.8 rectal mass, with a fungating external component, invading the levator ani and both anal sphincter muscles. There were no enlarged nodes, or distant metastasis on imaging. Following a multidisciplinary team meeting, she underwent a laparoscopic sigmoid loop colostomy to address the obstructive symptoms first, followed by the delivery of 25 Gy in 5 fractions of radiation therapy.
An ELAPE was performed through a perineal-first approach a week after RT. The patient was initially positioned prone for the perineal phase (Fig. 1B), then shifted to lithotomy for the abdominal phase of resection. The tumor extirpation resulted in a 10 x 8 cm perineal defect. (Fig. 1C) A myocutaneous gracilis flap reconstruction was used to address the defect. (Fig. 1D).

Results/Outcomes: The patient had an unremarkable postoperative course. The mesorectal excision was graded as complete. Histopathology showed a well-differentiated adenocarcinoma, with negative margins of resection (Stage IIA, ypT3N0M0). The patient has since started adjuvant systemic treatment with FOLFOX6.

Conclusion/Discussion: The urgent need to remove the tumor due to its debilitating effects led us to proceed with short-course RT (SCRT) followed by surgery after a week, in line with the regimen from the Swedish Rectal Cancer Trial. This approach effectively managed the symptoms, while being able to proceed with cancer treatment with little delay. Although being employed less, SCRT remains to have utility in select cases.
To achieve optimal visualization, we did a prone perineal-first approach. This enhances pelvic exposure, allowing the operator to work along the correct planes of dissection. However, concerns may arise with this approach, such as undetected metastatic disease (e.g. liver metastasis, carcinomatosis), or an unresectable primary tumor. In this case, the patient had a recent laparoscopic procedure that allowed for abdominal evaluation. In other patients, we routinely perform a diagnostic laparoscopy. This, however, means multiple repositioning.
While there is limited evidence on the oncologic benefits of a prone perineal-first approach for ELAPE, we found it appropriate for this case. The use of this approach permitted achieving a complete TME specimen and oncologically-sound histopathologic results, which may translate to desirable long-term outcomes. More studies are needed to fully validate its effectiveness and benefits.

A Perineal-First Approach Extralevator Abdominoperineal Excision with Myocutaneous Gracilis Flap Reconstruction for Locally-Advanced Rectal Cancer
Figure 1. (A) The patient presented with a rectal mass with extraluminal extension that had debilitating effects. (B) The patient was placed in prone position for the perineal phase. (C) A perineal defect measuring 10 x 8 cm was left after removal of the TME specimen that was graded as “complete.” (D) On dorsal lithotomy position, the left medial thigh was prepared as donor site. The marked site was developed to be the skin island used to cover the defect. The distal end of the gracilis muscle was transected from its insertion, and the flap was tunneled to the perineum to cover the defect. PGH, 2024.