Real-World Data of Retroperitoneal Tumor Surgeries Performed by Gastroenterological Surgeons in Japan: Analysis Based on the National Clinical Database

Ann Gastroenterol Surg. 2026 Feb 24;10(4):1331-1336. doi: 10.1002/ags3.70204. eCollection 2026 Jul.

ABSTRACT

BACKGROUND: Retroperitoneal tumors (RPTs) are rare and anatomically complex neoplasms, for which surgery remains the mainstay of treatment. However, real-world data on their surgical management in Japan have been limited.

OBJECTIVE: To describe the clinical characteristics and short-term outcomes of patients undergoing resection for RPTs in Japan, based on data from gastroenterological surgical practice.

METHODS: This study analyzed data from the Japanese National Clinical Database (NCD) for gastroenterological surgery. A total of 4948 patients with RPT who underwent surgery between 2019 and 2021 were included.

RESULTS: There were 2360 men (47.7%) and 2588 women (52.3%), with a median age of 66 years. RPTs were histologically classified as malignant in 75.3% and benign in 24.7% of cases. The median operative time was 205 min, and the median blood loss was 150 mL. Postoperative complications occurred in 23.9% of patients, with 7.5% experiencing severe complications (Clavien-Dindo grade III or higher). The 30 day postoperative mortality rate was 0.5%, and the perioperative mortality rate was 1.0%.

CONCLUSION: This analysis demonstrates that a substantial number (approximately 1650 per year) of RPTs surgeries are performed annually by gastrointestinal surgeons in Japan, and that the short-term surgical outcomes are acceptable. These data provide an important reference to exhibit the current surgical practice in Japan and to develop future strategies for RPTs.

PMID:42395133 | PMC:PMC13326821 | DOI:10.1002/ags3.70204