Validation of the Southampton Difficulty Scoring System in Robotic Liver Surgery and Development of the International RoboLiver Difficulty Scoring System.
El Adel, Soufyan Pilz da Cunha, Gabriela Liu, Rong Sucandy, Iswanto Di Benedetto, Fabrizio D'Hondt, Mathieu Vrochides, Dionisios Croner, Roland Sparrelid, Ernesto Ratti, Francesca
El Adel, Soufyan
Pilz da Cunha, Gabriela
Liu, Rong
Sucandy, Iswanto
Di Benedetto, Fabrizio
D'Hondt, Mathieu
Vrochides, Dionisios
Croner, Roland
Sparrelid, Ernesto
Ratti, Francesca
Abstract
BACKGROUND: Robotic liver surgery (RLS) provides technical advantages over laparoscopic liver surgery (LLS), but no validated robotic-specific difficulty scoring system (DSS) exists. We evaluated the applicability of the Southampton DSS to RLS and developed a dedicated RLS difficulty model.
STUDY DESIGN: This multicenter retrospective cohort study included adults undergoing planned RLS across 24 international hepatobiliary centers. The Southampton DSS was assessed for calibration and discrimination in predicting intraoperative complications. Given limited performance, a robotic-specific model (International RoboLiver DSS) was developed using multivariable logistic regression with prolonged operative time (>280 minutes; 75th percentile) as a surrogate of technical difficulty. Model discrimination, calibration, and bootstrap internal validation were performed.
RESULTS: Among 1,497 RLS patients, higher Southampton DSS categories were associated with increased intraoperative complications (p=0.003); however, discrimination was poor (AUC 0.571, 95% CI 0.530-0.612) with miscalibration (slope 0.43; intercept 0.06). Independent predictors of prolonged operative time included neoadjuvant chemotherapy, prior extrahepatic surgery, lesion >50 mm, multiple lesions, bilobar disease, and technically or anatomically major resection. The International RoboLiver DSS demonstrated moderate discrimination (AUC 0.719, 95% CI 0.686-0.751) with excellent calibration (intercept 0.00; slope 1.14). Bootstrap validation confirmed model stability (corrected AUC 0.719).
CONCLUSIONS: Difficulty factors in RLS partially overlap with LLS but are not directly transferable. The International RoboLiver DSS provides a calibrated, robot-specific tool for preoperative complexity stratification and operative planning in RLS. External validation is required.
MIDER Authors
Date
2026-05-01
Type
Article
Subject
Robotic-Assisted Surgery, Liver
Collections
Citation
Journal of the American College of Surgeons. 2026 May 1.
Journal / Source Title
Journal of the American College of Surgeons
DOI
10.1097/XCS.0000000000001978
PMID
41989032
Publisher
Lippincott, Williams & Wilkins