Long-term rectal cancer outcomes better with laparoscopic vs robotic surgery

Three-year data from the REAL study has shown that robot-assisted resection of middle or low rectal cancer is associated with lower locoregional recurrence and disease-free survival (DFS) compared with the conventional laparoscopic approach.

The primary outcome of locoregional recurrence rate at 3 years was 1.6 percent (95 percent confidence interval [CI], 0.6–2.6) in the robotic group vs 4.0 percent (95 percent CI, 2.4–5.6) in the laparoscopic group (adjusted hazard ratio [aHR], 0.39, 95 percent confidence interval [CI], 0.19–0.80; p=0.03). [JAMA 2025;doi:10.1001/jama.2025.8123]

The result was consistent across subgroups defined by sex (p=0.64), BMI (p=0.67), height of tumour from the anal verge (p=0.87 for interaction), use of preoperative radiotherapy or chemoradiotherapy (p=0.99), T stage (p=0.86), N stage (p=0.75), or type of surgery (lower anterior or abdominoperineal resection; p=0.93).

DFS rate at 3 years was 87.2 percent in the robotic group vs 84.3 percent in the laparoscopic group (aHR, 0.67, 95 percent CI, 0.50–0.89; p=0.04). The benefit of robotic surgery for DFS varied based on tumour height (p=0.03). For low rectal cancer, robotic surgery yielded a substantially higher 3-year DFS rate compared with laparoscopic surgery (86.2 percent vs 77.6 percent; HR, 0.55, 95 percent CI, 0.38–0.81). Conversely, for middle rectal cancer, the robotic and laparoscopic approaches showed similar 3-year DFS rates (88.1 percent vs 88.7 percent; HR, 1.07, 95 percent CI, 0.69–1.65). The investigators advised caution when interpreting this subgroup data, since the risk estimates were obtained without multivariate adjustment and not sufficiently powered to specifically detect the heterogeneity of the treatment effect.

As for the 3-year overall survival rates, no significant difference was observed between the robotic and laparoscopic groups (94.7 percent vs 93.0 percent).

Favourable functional outcomes

Aside from the improvements in long-term oncologic outcomes, robotic surgery outperformed conventional laparoscopic surgery across multiple functional outcomes, including urinary, male and female sexual, and defecation function.

Compared with those in the laparoscopic group, patients in the robotic group also had lower International Prostate Symptom Scores (3 months: p<0.001; 6 months: p<0.001; 12 months: p=0.001), higher scores on the 5-item International Index of Erectile Function (3 months: p<0.001; 6 months: p<0.001; 12 months: p<0.001), higher scores on the Female Sexual Function Index (3 months: p<0.001; 6 months: p=0.008), and lower scores on the Wexner Continence Grading Scale (3 months: p<0.001; 6 months: p=0.01).

Chronic pain outcomes did not significantly differ between the two groups across all time points examined.

The REAL cohort included 1,240 patients with middle (>5–10 cm from the anal verge) or low (≤5 cm from the anal verge) rectal adenocarcinoma, enrolled at 11 centres across eight provinces in China. Rectal cancer was staged as cT1-T3, N0-N1, or ycT1-T3 Nx, and there was no evidence of distant metastasis.

The primary analysis included 1,171 patients, including 586 randomly allocated to the robotic group (mean age 59.1 years, 60.8 percent male) and 585 in the laparoscopic group (mean age 60.7 years, 60.5 percent male). The median follow-up duration was 43.0 months.

Mechanical arms lending a hand

“To our knowledge, this is the first trial to report the significant advantages of robotic surgery compared with conventional laparoscopic surgery in terms of improving long-term oncological outcomes for patients with middle or low rectal cancer,” according to the investigators.

The findings indicate that robotic surgical techniques, which incorporate three-dimensional vision, a stable camera platform, and flexible robotic arms, can address the limitations of laparoscopic surgery and improve surgical quality, they said.

For instance, in total mesorectal excision, “conventional laparoscopic instruments enter the pelvic cavity in a nearly vertical direction and there is a limited angle for operation in the horizontal direction. The narrow space can easily lead to interference among instruments and affect the quality of the surgery. However, when robotic instruments are used, the rotating wrist structure can move freely in a narrow space, resolving this issue,” the investigators explained.

Entering the operating theatre

“The [REAL trial] serves as a key benchmark in the era of robot-assisted surgery for rectal cancer,” noted Drs Min Jung Kim, Emmanouil Pappou, and J Joshua Smith, all from the Memorial Sloan Kettering Cancer Center in New York, New York, US, in a linked editorial piece. [JAMA 2025;doi:10.1001/jama.2025.7019]

However, Kim et al raised concerns regarding the generalizability and practical implications of the trial’s findings.

“The surgeons in the [REAL] trial were highly experienced, and the outcomes may not be easily reproduced across lower-volume institutions or without standardized training… Another critical issue is cost and accessibility. Robotic platforms entail substantial capital and maintenance investments, which may limit their adoption, particularly in resource-constrained settings,” they said.

Kim et al highlighted the need to develop structured training programs and credentialing pathways to ensure consistent surgical quality before robotic total mesorectal excision can be universally recommended. Meanwhile, policymakers and healthcare systems have to evaluate the oncological gains demonstrated in the REAL trial in light of the associated economic costs, they added.

“Robotic surgery for rectal cancer has transitioned from a novel alternative to a compelling frontrunner in oncological efficacy. It is no longer a question of whether it is safe or effective. Now, the question is how to scale the benefits of a robotic-assisted approach responsibly and equitably,” Kim et al said.