Current status and 10-year trends of reimbursed robot-assisted surgery in Japan: a nationwide claims-based study...

Since reimbursement under Japan's National Health Insurance system, robot-assisted surgery (RAS) has expanded rapidly. However, comprehensive cross-disciplinary analyses describing long-term adoption trends and regional variation remain limited. This study aimed to evaluate nationwide adoption and distribution of reimbursed RAS across surgical specialties in Japan.

We performed a population-based study using publicly available claims data from the National Database (NDB) Open Data (2014-2023). All procedures reimbursed as RAS as of fiscal year 2023, along with corresponding endoscopic and open procedures, were included. Ten-year trends in RAS volume were analyzed across surgical fields and procedure categories. For representative procedures in fiscal year 2023, prefecture-level and age- and sex-specific variations in surgical approach were examined.

By 2023, 47 reimbursed robotic procedures were classified into 20 categories across four surgical fields. Annual RAS volume increased markedly, reaching 95,845 procedures in 2023. Urology accounted for the largest share (40,673 cases), followed by gastrointestinal surgery and gynecology. Radical prostatectomy was the most common robotic procedure, followed by rectal resection and nephrectomy for malignant tumors. Robotic utilization was highest in urology; within gastrointestinal surgery, esophagectomy and rectal resection showed relatively high adoption. Substantial prefecture-level variation was observed, with patterns differing by procedure and not consistently correlating with minimally invasive surgery rates. RAS adoption was strongly associated with the number of certified robotic surgery proctors in several procedures. For selected procedures, including gastrectomy, robotic and minimally invasive utilization decreased with increasing age.

RAS has expanded rapidly in Japan, with marked procedural and regional variation. These population-level findings may inform implementation strategies and health policy for robotic surgery.