Liquid Biopsy Cell-free RNA-based Machine Learning Enables Preoperative Risk-Stratification of Uterine Leiomyosarcoma
Sören R Stahlschmidt1, Victor Lago2, Alba Machado-López3
1Carlos Simon Foundation, Valencia, Spain.
American Journal of Obstetrics and Gynecology
|July 23, 2026
Summary
A new blood test using circulating cell-free RNA (cfRNA) shows promise in distinguishing uterine leiomyosarcoma (UMS) from uterine leiomyoma (UM) before surgery. This machine learning model achieved high accuracy, offering potential for improved preoperative risk stratification.
Area of Science:
- Gynecologic Oncology
- Molecular Diagnostics
- Machine Learning in Medicine
Background:
- Distinguishing uterine leiomyoma (UM) from uterine leiomyosarcoma (UMS) preoperatively is challenging, impacting surgical decisions and patient outcomes.
- Current diagnostic methods like imaging and biomarkers lack sufficient accuracy for reliable differentiation.
- Plasma circulating cell-free RNA (cfRNA) offers a potential noninvasive biomarker for tumor classification.
Purpose of the Study:
- To develop and evaluate a plasma cfRNA-based machine learning classifier for preoperative differentiation of UMS from UM.
- To assess the diagnostic performance and biological generalizability of the developed classifier.
Main Methods:
- Prospective, multicenter study involving 102 women with suspected myometrial tumors.
- Plasma cfRNA profiles analyzed to train a 100-gene signature machine learning model.
- Diagnostic performance evaluated using AUROC, sensitivity, and specificity, with cross-validation and external cohort testing.
Main Results:
- A 100-gene cfRNA signature reliably differentiated UM from UMS with an AUROC of 0.868 (sensitivity 0.732, specificity 0.813).
- Performance was consistent across different age groups and robust in an independent external tissue cohort (AUROC 0.892).
- The classifier demonstrated biological and translational robustness.
Conclusions:
- Plasma cfRNA profiles show distinct differences between UMS and UM, suggesting potential for preoperative risk stratification.
- Further prospective validation is needed to establish an accurate diagnostic test.
- The positive predictive value of the test will be influenced by population prevalence.
