Mapping Metastatic Spread in Uterine Sarcoma: A Population-Based Analysis of First Metastatic Patterns and Outcomes

Area of Science:

• Oncology
• Gynecologic Oncology
• Cancer Epidemiology

Background:

• Uterine sarcoma is a rare malignancy with limited data on metastatic patterns and outcomes.
• Understanding the frequency, timing, and sites of metastasis is crucial for improving patient management.

Purpose of the Study:

• To characterize the incidence, timing, patterns of first distant metastasis, and post-metastatic survival in uterine sarcoma.
• To identify factors associated with overall survival (OS) and recurrence-free survival (RFS) in this patient population.

Main Methods:

• Population-based retrospective cohort study using data from the regional cancer registry of Saxony-Anhalt, Germany (2000-2025).
• Included 155 patients with uterine sarcoma (excluding carcinosarcoma).
• Analyzed metastatic disease (primary vs. metachronous), first metastatic sites, and survival using Kaplan-Meier and Cox regression models.

Main Results:

• Over one-third (34.8%) of patients developed metastatic disease, with 55.6% presenting at diagnosis.
• The lung was the most frequent site of first metastasis, followed by bone, peritoneum, and liver.
• Median post-metastatic OS was 12 months; advanced FIGO stage and failure to achieve tumor-free status were associated with worse OS.

Conclusions:

• Metastatic uterine sarcoma is common, often diagnosed at advanced stages, and characterized by poor post-metastatic survival.
• Lung metastases are the predominant pattern of initial distant spread.
• Findings highlight the aggressive nature of uterine sarcoma and the importance of thorough staging at diagnosis.