Laparoscopic and Robotic Procedures Combined Surgery (LARCS): A Novel Approach to Trainee Participation in Robotic Gastrectomy.

BACKGROUND: Robotic gastrectomy (RG) for gastric cancer reduces morbidity and achieves long-term outcomes comparable to laparoscopy. However, RG is typically a solo-surgeon procedure performed by expert console surgeons, limiting trainees' operative experience. To address this issue, we developed Laparoscopic and Robotic procedures Combined Surgery (LARCS), in which the patient-side surgeon (PSS) performs selected surgical maneuvers, including dissection, clipping, and stapling, using laparoscopic instruments under the supervision of the console surgeon. METHODS: We retrospectively analyzed 96 patients who underwent robotic distal or subtotal gastrectomy at Kitasato University Hospital between January 2019 and December 2023. Patients were divided into a conventional RG group (CRG; n = 60) and a LARCS group (n = 36). Propensity scores were estimated based on age, sex, body mass index, American Society of Anesthesiologists status, and clinical T and N categories. Cardinality matching within a 0.2-standard-deviation caliper of the logit of the propensity score yielded 23 matched pairs, with all absolute standardized mean differences for the matching covariates < 0.1. Perioperative outcomes and PSS participation were compared. RESULTS: After matching, adequate balance was achieved for all matching covariates, with absolute standardized mean differences ranging from 0 to 0.062. Operative time was 406 min in the LARCS group and 373 min in the CRG group (p = 0.110). Estimated blood loss tended to be greater with LARCS (51 vs. 6 mL, p = 0.070). Any postoperative complication occurred in 6 and 5 patients, respectively (p = 1.000), and major complications occurred in 2 and 0 patients, respectively (p = 0.500). Median PSS operative time was 108 min, corresponding to 26.6% of the total operative time in LARCS, versus 0 min in CRG (p < 0.001). CONCLUSIONS: LARCS provided patient-side trainees with supervised, instrument-based first-operator participation for approximately one-quarter of the operative time, supporting its feasibility as a complementary approach to trainee participation during robotic gastrectomy. Further prospective studies incorporating objective competency-based assessments are required to determine its educational effectiveness and safety.