Federated learning-based CT liver tumor detection using a teacher‒student SANet with semisupervised learning

BMC Med Imaging. 2025 Jul 1;25(1):250. doi: 10.1186/s12880-025-01761-7.

Abstract

Background: Detecting liver tumors via computed tomography (CT) scans is a critical but labor-intensive task. Extensive expert annotations are needed to train effective machine learning models. This study presents an innovative approach that leverages federated learning in combination with a teacher‒student framework, an enhanced slice-aware network (SANet), and semisupervised learning (SSL) techniques to improve the CT-based liver tumor detection process while significantly reducing its labor and time costs.

Methods: Federated learning enables collaborative model training to be performed across multiple institutions without sharing sensitive patient data, thus ensuring privacy and security. The teacher-student SANet framework takes advantage of both teacher and student models, with the teacher model providing reliable pseudolabels that guide the student model in a semisupervised manner. This method not only improves the accuracy of liver tumor detection but also reduces the dependence on extensively annotated datasets.

Results: The proposed method was validated through simulation experiments conducted in four scenarios, and it demonstrated a model accuracy of 83%, which represents an improvement over the original locally trained models.

Conclusions: This study presents a promising method for enhancing the CT-based liver tumor detection while reducing the incurred labor and time costs by utilizing federated learning, the teacher-student SANet framework, and SSL techniques. Compared with previous approaches, the proposed method achieved a model accuracy of 83%, representing a significant improvement.

Trial registration: Not applicable.

Keywords: Federated learning; Liver tumors; Medical image analysis; Semisupervised learning; Teacher–student framework.

MeSH terms

  • Federated Learning
  • Humans
  • Liver Neoplasms* / diagnostic imaging
  • Machine Learning*
  • Radiographic Image Interpretation, Computer-Assisted* / methods
  • Supervised Machine Learning*
  • Tomography, X-Ray Computed* / methods