# Robotic Intracorporeal Single-Stapled Anastomosis (RISS) is Associated with Lower Anastomotic Leakage Rates than the Double-Stapled Technique After Minimally Invasive Total Mesorectal Excision for Rectal Cancer

## TL;DR

A robotic single-stapled technique for rectal cancer surgery reduces anastomotic leakage and complications compared to the traditional double-stapled method.

## Contribution

RISS offers a safer, reproducible, and potentially cost-effective alternative to the double-stapled technique for rectal cancer surgery.

## Key findings

- RISS had a significantly lower 90-day anastomotic leakage rate (5.6% vs. 16.7%).
- RISS reduced overall morbidity and hospital stay compared to the double-stapled technique.
- Using more than three stapler firings increased the risk of anastomotic leakage.

## Abstract

Alternatives to the double-stapled (DS) technique for creating anastomoses after minimally invasive total mesorectal excision (TME) have been proposed to reduce complications and costs. Robotic intracorporeal single-stapled anastomosis (RISS) was developed as a technically intuitive approach. Standardizing such an intracorporeal robotic technique—which achieves adequate pelvic exposure, precise rectal transection, and secure anastomosis construction—may optimize outcomes, particularly anastomotic leakage (AL).

A cohort study was conducted using our prospective institutional database and included patients < 80 years who underwent minimally invasive elective TME for extraperitoneal rectal cancer. Patients were allocated to the DS (abdominal stapled transection with double-stapled anastomosis) or RISS (robotic intracorporeal rectal transection with single-stapled anastomosis) groups. The exclusion criteria were nonrestorative procedures, intersphincteric resection, open surgery, and no indocyanine green perfusion assessments. The primary endpoint was 90-day clinical or radiological AL.

Among 380 TMEs, 167 met the inclusion criteria (71 RISS; 96 DS). The 90-day AL rate was significantly lower in the RISS group (5.6% vs. 16.7%; p = 0.032). Reintervention (1.4% vs. 10.4%; p = 0.025), overall morbidity (33.3% vs. 52.5%; p = 0.014), and length of stay (p < 0.0001) were lower following RISS. Multivariable analysis revealed that DS technique (odds ratio [OR] 3.3; p = 0.038) and comorbidities (OR 3.1; p = 0.028) independently predicted AL. Each additional stapler firing increased the risk of AL (OR 1.62; p = 0.016), and ≥3 firings predicted AL (OR 4.92; p = 0.011).

Compared with DS, RISS was associated with lower anastomotic leakage, morbidity, and reintervention and shorter hospitalization. This standardized robotic approach is safe, reproducible, and potentially cost effective.

The online version contains supplementary material available at 10.1245/s10434-025-18742-3.