V35 - Large Anal Cancer Involving Labia and Vagina, Useful Tips for R0 Resection (Obese Female, Robotic and Perineal Resection)

Purpose/Background: This video presents a case of a large anal cancer involving the labia and vagina in an obese female patient. Useful tips for R0 robotic and perineal resection will be demonstrated.

Methods/Interventions: Our patient is a 68 y/o female with a neglected anal squamous cell carcinoma who failed the Nigro protocol 10 months earlier. Her BMI is 40, and she presented malnourished with a diverting colostomy

Our plan was to perform a robotic proctectomy with transabdominal levator transection followed by perineal resection with posterior vaginectomy. We wanted to utilize the excessive nonradiated skin of the buttocks and avoid any extensive flap closure because of malnutrition. Further, we wanted to create a retroversed uterine flap followed by primary wound closure with wound vac support.

We utilized the robotic platform with 2 additional laparoscopic ports. Here, we demonstrate that the presence of a colostomy should not be an obstacle to optimal robotic port placement.

Once the TME was completed, the levators were exposed, knowing they were not involved in the cancer. Anteriorly, the dissection was carried to the mid-vaginal level.

Here, we demonstrate the transection of the levators, a technique first described by the authors in 2011. In this case, transection involves the domes of the ilial-coccygeal muscles laterally, and the coccygeus muscles and anal-coccygeal ligament posteriorly. In this technique, the coccyx can be entirely preserved, resulting in a much smaller pelvic floor defect.

In the posterior midline, bleeding precoccygeal vessels occasionally need to be controlled

Subsequently, the patient is placed in the prone position. Here we demonstrate the excessive buttock tissue, which had not been irradiated, and can be used for successful reconstruction of a large perineal defect.

Tumor-specific wide local excision is carried out and extended into the ischio-anal fossa until the posterior levators are exposed just beneath the tip of the coccyx. A rendezvous with the previous plane of dissection is achieved. Because of the transabdominal levator transection, this part of the procedure becomes easy, leading to the extraction of the previously mobilized rectum.

The posterior wall of the vagina is transected above the tumor.

Repeated intra-vaginal palpation can be performed with frequent glove changes to guide the dissection.

Labial resection is then performed under finger dissection.

The specimen is subsequently passed off the operating field and examined.

The resulting perineal defect is evaluated.

The uterine flap is created by bilateral transection of the round ligaments next to the uterine body while identifying both ureters. Despite the small uterine size, the majority of the deep perineal defect can be successfully closed by retroflexing the uterus and stitching it to the coccyx.

We then bring our attention to reconstructing the vaginal defect without functional intent. Both lateral walls are reapproximated, resulting in retubularization of the vaginal canal. The same maneuver is performed on both transected labia, thus recreating the perineum. We placed 2 additional perineal drains, expecting significant drainage because of hypoalbuminemia.

Results/Outcomes: A pathologic review of the specimen revealed an R0 resection.
The patient developed a small area of wound necrosis, but this subsequently healed.

Conclusion/Discussion: We present a case of a large anal cancer involving the labia and vagina in an obese female patient. R0 robotic and perineal resection were demonstrated.