A 26-year-old female was diagnosed with a clinical T3bNx rectal adenocarcinoma at 3 cm from the anal verge. The tumor was found to be DNA-mismatch-repair deficient and germline testing showed a pathogenic mutation in the PMS2 gene, consistent with Lynch syndrome. After neoadjuvant chemoradiation, she expressed a strong desire to avoid surgery and permanent colostomy. She received FOLFOX, achieved an excellent clinical response, and underwent a 'watch and wait' approach to her rectal cancer. Unfortunately, an interval assessment 2.5 months later revealed tumor regrowth. The patient was counselled and agreed to undergo abdominoperineal resection. The Xi robotic platform was utilized, with four robotic and three assistant ports. Initial exploration revealed a highly redundant sigmoid colon. Instead of the standard approach which begins with medial mobilization of the left colon, we undertook a pelvis-first approach, completing pelvic dissection first, while leaving the left colon tethered to the sidewall. The posterior aspect of the superior rectal artery was followed to enter the total mesorectal plane. Total mesorectal dissection was carried out posteriorly, laterally and anteriorly. Levator ani was widely divided trans-abdominally under direct vision. After pelvic dissection, vascular dissection and ligation at inferior mesenteric artery was completed. Left colon was finally medially mobilized and mesentery was divided after preserving the left colic artery. After completing perineal dissection, specimen was removed after diving the left colon trans-anally. End colostomy was created laparoscopically, obviating the need for an abdominal incision.