EBioMedicine (Jun 2021)

CT radiomics-based machine learning classification of atypical cartilaginous tumours and appendicular chondrosarcomas

  • Salvatore Gitto,
  • Renato Cuocolo,
  • Alessio Annovazzi,
  • Vincenzo Anelli,
  • Marzia Acquasanta,
  • Antonino Cincotta,
  • Domenico Albano,
  • Vito Chianca,
  • Virginia Ferraresi,
  • Carmelo Messina,
  • Carmine Zoccali,
  • Elisabetta Armiraglio,
  • Antonina Parafioriti,
  • Rosa Sciuto,
  • Alessandro Luzzati,
  • Roberto Biagini,
  • Massimo Imbriaco,
  • Luca Maria Sconfienza

Journal volume & issue
Vol. 68
p. 103407

Abstract

Read online

Background: Clinical management ranges from surveillance or curettage to wide resection for atypical to higher-grade cartilaginous tumours, respectively. Our aim was to investigate the performance of computed tomography (CT) radiomics-based machine learning for classification of atypical cartilaginous tumours and higher-grade chondrosarcomas of long bones. Methods: One-hundred-twenty patients with histology-proven lesions were retrospectively included. The training cohort consisted of 84 CT scans from centre 1 (n=55 G1 or atypical cartilaginous tumours; n=29 G2-G4 chondrosarcomas). The external test cohort consisted of the CT component of 36 positron emission tomography-CT scans from centre 2 (n=16 G1 or atypical cartilaginous tumours; n=20 G2-G4 chondrosarcomas). Bidimensional segmentation was performed on preoperative CT. Radiomic features were extracted. After dimensionality reduction and class balancing in centre 1, the performance of a machine-learning classifier (LogitBoost) was assessed on the training cohort using 10-fold cross-validation and on the external test cohort. In centre 2, its performance was compared with preoperative biopsy and an experienced radiologist using McNemar's test. Findings: The classifier had 81% (AUC=0.89) and 75% (AUC=0.78) accuracy in identifying the lesions in the training and external test cohorts, respectively. Specifically, its accuracy in classifying atypical cartilaginous tumours and higher-grade chondrosarcomas was 84% and 78% in the training cohort, and 81% and 70% in the external test cohort, respectively. Preoperative biopsy had 64% (AUC=0.66) accuracy (p=0.29). The radiologist had 81% accuracy (p=0.75). Interpretation: Machine learning showed good accuracy in classifying atypical and higher-grade cartilaginous tumours of long bones based on preoperative CT radiomic features. Funding: ESSR Young Researchers Grant.

Keywords