The First Report on Liver Resection Using the Novel Japanese hinotori™ Surgical Robot System: First Case Series Report of 10 Cases

Background: In Japan, the hinotori (TM) surgical robot system (Medicaroid Corporation, Kobe, Japan) was approved for gastrointestinal surgeries in October 2022. This report details our initial experience performing liver resection using the hinotori (TM) system. Methods: Ten patients, who were assessed as cases that would benefit from the robot-assisted procedure, underwent liver resections using the hinotori (TM) system at Fujita Health University, Okazaki Medical Center, between August 2023 and October 2024. The backgrounds (patient, tumor, and liver function conditions, along with types of liver resections and previous surgical procedures) and short-term outcomes (operation time, blood loss, postoperative complications, open conversion, length of hospital stay, and mortality) of the cases were evaluated. Results: Eight cases of partial liver resection, one extended left medial sectionectomy, and one left hemi-hepatectomy were performed. Six cases of hepatocellular carcinomas, three cases of liver metastases, and one case of hepatolithiasis were included. There were seven male and three female patients with a median age of 70 years. Three physical status class III and seven class II patients were included. The median body mass index was 24. Five patients had previous upper abdominal surgical histories and five patients had liver cirrhosis. The median operation time was 419.5 min, and the median intraoperative blood loss was 276 mL. An open conversion in one hepatocellular carcinoma case was carried out due to bleeding from collateral vessels in the round ligament. The median length of hospital stay was 7.5 days. A grade IIIa complication (delayed bile leakage) was developed in one case. All patients with tumors underwent R0 resection. There were no cases of mortality. Conclusions: Liver resection using the hinotori (TM) system was feasibly performed. This study reports the first global use of the hinotori (TM) system for liver resection.