Journal of Tumor Research
Open Access

Abstract

Soft-Tissue Tumor Reporting and Data System (ST-RADS): MRI Reporting Guideline with Multi-Institutional Validation Study of Musculoskeletal Extremity Tumors

Avneesh Chhabra*, Oganes Ashikyan, Raghu Ratakonda, Gitanjali Bajaj, Uma Thakur, Parham Pezeshk, Yin Xi, Marwa Zaid, Alexandra Callan, William Murphy, Rajendra Kumar and Behrang Amini

Background: To our knowledge, no current guideline exists in outlining follow-up or interventional strategies in musculoskeletal soft tissue tumor management. To develop and validate Soft-tissue Tumor Reporting and Data System (ST-RADS) with the hypothesis that the proposed guideline reliably and accurately assists in separating benign from malignant musculoskeletal soft tissue tumors.

Methods: This is a multi-institutional cross-sectional study of soft-tissue masses. An expert consensus agreement was reached for ST-RADS categories using the terminology from WHO classification. Adipocytic tumors, T2-hyperintense and T2-hypointense masses of extremities with a wide spectrum of histologies were assessed. MRI categories were: STRADS 0-incomplete imaging, I-no lesion identified, II-definitely benign, III-probably benign, IV-indeterminate or suspicious for malignancy, V-highly suggestive of malignancy, and VI-known biopsy-proven malignancy or recurrence. Eight readers’ evaluated cases and ICC (Intra-Class Correlation) and AUC (Area Under the Curve) were calculated.

Results: 200 soft tissue masses were tested. There was good inter-reader agreement with ICC (Intra-Class Correlation)=0.72 [95% CI=0.64-0.79] and 0.69 [95% CI=0.59-0.70] for adipocytic and T2-hyperintense, and fair, 0.48 [95% CI=0.35-0.62] for T2-hypointense masses. The sensitivity and specificity for detection of malignancy were 96% and 63%, 93% and 71%, 64% and 84% for adipocytic, T2-hyperintense, and T2-hypointense masses, respectively. The AUC (Area Under the Curve) was 0.79-0.89.

Conclusion: ST-RADS guideline using standardized terminology stratifies musculoskeletal tumors into benign and malignant categories and provides management strategy. This MRI-based guideline is meant to be a "dynamic" document that can be further refined and updated in response to future user feedback and as new scientific data becomes available.

Published Date: 2022-12-27; Received Date: 2022-11-25