SS201 - Robotic TME For T4 Rectal Cancer Is Feasible And Safe, Even With Multivisceral Resection

Purpose/Background: In the era of total neoadjuvant therapy, locally advanced rectal cancer invading beyond the mesorectal fat (T4) continues to pose significant surgical challenges, often requiring multivisceral resections to achieve negative microscopic margins. While modern robotic platforms offer enhanced precision and visualization that allow for advanced and complex procedures to be completed laparoscopically, feasibility and outcomes data in this patient population are limited. We aimed the examine the surgical approaches and outcomes of T4 rectal cancer patients at our institution.

Methods/Interventions: Consecutive patients with T4 locally advanced rectal cancer, treated with curative intent at our NAPRC-accredited center (2021-2023), were retrospectively reviewed. Surgical procedures and outcomes were assessed. Primary outcome was R0 resection; secondary outcomes were anal sphincter preservation, post-operative morbidity, cancer recurrence, and cancer mortality. Disease-free survival was determined via Kaplan-Meier analysis.

Results/Outcomes: A total of 40 patients were included with a median age of 60 years and 65% were male. At the time of initial diagnosis, 30% of patients had distant metastases (n=12). All patients received neoadjuvant therapy (75% TNT, 15% chemotherapy only, 5% chemoradiation only, 5% immunotherapy only), with 5 patients achieving complete tumor response and non-operative management. Thirty-five patients required TME, with 66% requiring multivisceral resection (n=23/35). Robotic assisted laparoscopic TME was performed in 91% of patients (n=32/35), with 1 conversion to open (3%). Open resection was performed in 3 patients (9%) that were ineligible for minimally invasive resection due to simultaneous multisegmental hepatectomies or HIPEC therapy. An R0 resection was achieved in 94% of all cases (n=33/35) with 2 specimens (6%) having a positive microscopic circumferential margin (R1). 69% of patients were eligible for sphincter preserving surgery and restoration of intestinal continuity was successful in 96% of those patients (n=23/24). Major post-operative morbidity (Clavien-Dindo ≥3) occurred in 29% of patients (n=10), with no 30-day mortality. At a median follow-up of 32 months, the local tumor recurrence rate was 8% (3/40) and the cumulative estimated disease-free survival of patients with T4 M0 rectal cancer was 89% (95% C.I. 84-93%).

Conclusion/Discussion: Robotic TME for T4 rectal cancer, even when multivisceral resection is required, is demonstrated to be a feasible, safe and oncologically sound approach in a high-volume center. The favorable rates of R0 resection, sphincter preservation, and low morbidity observed support the expanded application of robotics in advanced rectal cancer.

Patient Selection Flow Diagram
Patient Characteristics and Outcomes