Stepwise Approach for Robotic Total Pelvic Exenteration with En Bloc Presacral Fascia in T4b Rectal Cancer.

Background: The T4 rectal cancers indicate beyond total mesorectal excision (TME) plane dissection with en bloc multivisceral resection for achieving R0 resection. Recent studies emphasize the feasibility and safety of minimally invasive surgery in selected T4 rectal cancers. This study demonstrates a stepwise approach for robotic total pelvic exenteration (TPE) with en bloc presacral fascia in T4b rectal cancer, focusing on the internal iliac vessel branches management and presacral fascia resection.

Methods: A 58-year-old man with locally advanced mid-rectal cancer underwent total neoadjuvant treatment per multidisciplinary team consensus, followed by robotic TPE with en bloc presacral fascia. After managing the inferior mesenteric vessels, the posterior aspect of the rectum was dissected in both TME and presacral fascia plane. Lateral dissection was then proceeded into the extravascular plane, securing the obturator nerve. Subsequently, the uretero-hypogastric and vesico-hypogastric fascia were dissected apart, permitting the internal iliac branches and lymph nodes dissection. After vas deferens and ureteric division, anterior dissection into the Retzius space was completed. The dorsal venous complex was controlled. The specimen was removed en bloc following the urethral and rectal transection.

Results: The pathology reported ypT4bN1a with negative all resected margins. The patient was discharged on postoperative Day 5 without any perioperative complications. The 6-month postoperative CT scan showed neither local recurrence nor distant metastasis.

Conclusions: Minimally invasive approaches for T4 rectal cancers are increasingly utilized. This successful operation confirms the safety and feasibility in selected cases, expanding the potential of minimally invasive surgery for more complex scenarios.