MRI-BASED osseous tumour reporting and data system (OT-RADS): clinical experience of prospective implementation and...

To evaluate clinical performance and diagnostic accuracy of the MRI-based Osseous Tumour Reporting and Data System (OT-RADS) compared with traditional descriptive impressions.

After prospective integration of OT-RADS into the electronic dictation system, fellowship-trained musculoskeletal radiologists applied OT-RADS scoring in routine bone tumour reporting. This retrospective review included consecutive patients from July 2021 to May 2024, aged 17-100 years, with extremity or body wall osseous lesions evaluated by MRI and confirmed by surgery, biopsy, or benign follow-up. Demographics, imaging findings, lesion characteristics, biopsy results, treatments, and outcomes were collected. Diagnostic accuracy was compared using McNemar's test.

The study included 352 patients (60.2 % female, mean age 54.7 ± 15.7 years). Most lesions (66.1 %) were managed conservatively, while surgery and chemotherapy each accounted for 8.4 %. Biopsy was performed in 18.8 %. The distribution included OT-RADS I (4.8 %), II (46.1 %), III (18.2 %), and malignant-suspicion categories IV-V (36.1 %). Outcomes were favorable in 60.8 % of patients. OT-RADS demonstrated higher diagnostic accuracy than descriptive impressions (95.4 % vs. 88.0 %; p<.0001), particularly in biopsy-confirmed cases (84.6 % vs. 61.5 %; p<.0001). Accuracy was consistently superior across benign (II-III; p=.003) and malignant lesions (IV-V; p<.001), with subgroup analysis confirming significance for OT-RADS IV (p=.0078) and V (p=.0156).

OT-RADS significantly outperforms descriptive reporting in accuracy for benign and malignant bone tumours. These results support broader adoption of OT-RADS as a standardized framework to stratify lesion risk, optimize management, and improve patient outcomes.