Robotic Surgery Proves Its Mettle for Liver Cancer

Fully robotic liver resection was safe and effective for patients with hepatocellular carcinoma (HCC) compared with open liver resection, a cohort study found.

Propensity score-matched analysis showed “better perioperative tolerability … based on clinical, oncologic, and technical criteria” compared with open resection, reported Fabrizio Di Benedetto, MD, PhD, of the University of Modena and Reggio Emilia in Modena, Italy, and colleagues.

Robotic liver resection had longer operative times (295 vs 200 minutes, including docking, P<0.001) but a shorter length of stay (4 vs 10 days, P<0.001) and fewer ICU admissions (6.6% vs 19.8%, P=0.002).

It also had a lower incidence of liver failure after hepatectomy than open resection (7.5% vs 28.3%, P=0.001), without any cases of grade C failure, the authors wrote in JAMA Surgery.

Postoperative complication rates were similar between groups overall, but open resection patients were at greater risk of developing severe complications based on the Clavien-Dindo grade (11.3% vs 2.8%, P=0.029).

Robotic liver resection “may reduce morbidity, expanding the potential number of patients able to receive treatment from which they are currently excluded because of the risk of liver decompensation,” the group concluded.

Overall survival came out similar at 90 days between robotic and open surgery (99.1% vs 97.1%) but at 24 months was actually numerically better in the robotic group (86.9% vs 83.8%).

Tumor recurrence-related mortality was similar between robotic and open surgery groups at 24 months (8.8% vs 10.2%). A sensitivity analysis that included all relevant prognostic factors found similar overall survival results as well.

Although minimally invasive liver surgery has been shown to be safe and effective for resecting primary and metastatic liver tumors, there is still more to learn about complex laparoscopic resections, Di Benedetto’s group noted. Robotic liver resection is a minimally invasive approach that may lower the risk of conversion to open resection for complex hepatectomies.

Robotic surgery for right or extended right hepatectomy has previously shown benefits over laparoscopic surgery. Despite the numerous technical advantages of robotic surgery — such as increased stability, instrument flexibility, and magnified 3D vision — long-term oncologic outcomes are still debated, and costs are known to be higher than traditional surgery.

While researchers could not perform a cost-effectiveness analysis in this study, they pointed to the intuitive advantage of an average difference of 6 days of hospitalization between interventional groups, writing it “represents a major cost savings for any hospital,” in addition to the fewer ICU admissions and severe complications.

For this study, Di Benedetto and colleagues retrospectively examined data on 398 patients who underwent robotic liver resection (n=158) or open liver resection (n=240) for HCC from Jan. 1, 2010 to Sep. 30, 2020.

After propensity-score matching, 106 robotic resection patients treated at four centers in Europe and the U.S. were matched with 106 patients who underwent open resection at an international HCC surgery referral center in Italy with experience in nonrobotic, minimally invasive surgery, “to reduce the potential selection bias from the robotic centers.”

For robotic procedures, the da Vinci Si or Xi platform were used, with parenchymal transection conducted via a Kelly clamp crush technique with ultrasonic or radiofrequency advanced hemostasis energy devices. Tumor mapping was performed using indocyanine green (ICG) fluorescence for visualization at a dose of 0.25 mg/kg 12 hours prior to surgery or 1 mg ICG at induction.

Before propensity matching, the median age was younger among the robotic surgery hospitals’ patients than in the open resection hospital’s validation cohort (66 vs 70). About 79% of the patients were men. After propensity score matching, the median age was 67-69 and the cohort included 80-83% men. Average BMI ranged from 26-28. Notably, 3.2% of the robotic surgery group underwent intraoperative conversion to open resection.

No significant differences were seen in blood transfusions between groups (8.5% for both) or in the quantity of packed red blood cell units transfused (8.5% for both).

Propensity score matching made the two groups “homogeneous on the basis of not only baseline characteristics but also surgical difficulty and preoperative risk of tumor recurrence, representing an important refinement in this kind of analysis,” Di Benedetto’s group wrote.

However, the authors also acknowledged limitations, including potential bias arising from the non-randomized, retrospective study design.