# Hepatic resection for ovarian cancer in Germany: a nationwide epidemiological study based on DRG (diagnosis-related groups) data (2020–2024)

## TL;DR

This study analyzed liver surgery trends for ovarian cancer in Germany from 2020 to 2024 using hospital billing data.

## Contribution

The paper provides the first nationwide epidemiological analysis of hepatic resections for ovarian cancer in Germany.

## Key findings

- Hepatic resections for ovarian cancer were performed regularly, with stable annual case numbers between 2020 and 2024.
- Most surgeries were local excisions, and procedures were mainly conducted in large public hospitals.
- The study highlights the need for updated guidelines and further research on liver metastases in ovarian cancer.

## Abstract

Hepatic metastases from epithelial ovarian cancer (EOC) represent an advanced disease stage, yet national guidelines provide no standardized recommendations for liver resection. This study aimed to describe the national trends and patterns of hepatic resections in EOC patients based on German hospital billing data (DRG system) from 2020 to 2024.

A retrospective epidemiological analysis was conducted using InEK (Institute for Hospital Remuneration Systems) datasets from 2020 to 2024. We extracted data related to diagnosis ICD code C56 (malignant neoplasm of the ovary) and OPS codes for hepatic resections (5-501.0, 5-502.0, 5-502.2, 5-502.3, 5-502.4, 5-502.5, 5-502.6). Case numbers, procedure frequency, hospital characteristics, and DRG classifications were analyzed.

A total of 1,273 hepatic resections were performed in patients with ovarian cancer between 2020 and 2024. Annual case numbers ranged from 225 to 283, indicating stable surgical practice over time. Local excisions / atypical resections accounted for the majority (n = 1,165; 91%), while segmentectomies (n = 85; 6.7%) and major resections (n = 23; 1.8%) were less frequent but consistently performed. Age group analysis showed that the largest proportion of patients undergoing hepatic resection were aged 65–74 years (range 23%–27% yearly). followed by the 60–64 and 55–59 age groups. Younger patients (< 40 years) represented less than 5%. Most procedures (54.6%) were conducted in public hospitals with ≥ 1000 beds, with additional contributions from private non-profit (20.9%) and private for-profit (10.5%) institutions. A gradual increase in the share of private institutions was observed over time. The mean hospital stay varied by resection type: 16.7 days for local excisions, 17.1 days for segmentectomies, and 20.1 days for major resections.

Hepatic resection for ovarian cancer is performed regularly in Germany, primarily at high-volume centers, suggesting a growing clinical acceptance of aggressive cytoreduction strategies despite the absence of formal recommendations. Our findings underline the need for prospective, multicenter studies and guideline updates addressing hepatic metastases in ovarian cancer.