Soft tissue reporting and data system (soft tissue-RADS): framework for radiologists specializing in imaging of musculoskeletal tumors and tumor-like lesions.

Soft tissue-RADS scoring system for musculoskeletal (MSK) tumor and tumor-like lesions is recently published. The system includes diagnostic MRI flowcharts and algorithms for lipomatous masses, cyst-like or high-water content masses, and indeterminate-solid appearing masses with consistent and standardized management recommendations. MSK radiology and cancer imaging training commonly provides the essential skills needed to render appropriate prospective diagnosis for many non-neoplastic tumor-like lesions and various commonly encountered sarcomas. Such trained readers may benefit from additional advanced algorithms to accurately identify and categorize different benign tumors and sarcomas and correctly input them in the soft tissue-RADS scoring system. These algorithms are built from a comprehensive literature search to establish an evidence-based composite and are supported by the expert opinions of the multidisciplinary ACR-soft tissue-RADS team. In this article we provide (1) a literature review of multimodality imaging, immunopathology, and clinical findings of soft tissue tumors and tumor-like lesions, presented in 7 tables (condensed from the 12 tables published in the WHO classification of soft tissue tumors) with respective table summaries; (2) a suggested modality-based lexicon; and (3) advanced diagnostic algorithms for trained readers based on published evidence and expert opinion that feed into the soft tissue-RADS scoring system (categories 1-6). The purpose of this work is to provide comprehensive guidance on soft tissue-RADS scoring to help streamline care for soft tissue tumors and tumor-like lesions and optimize patient outcomes.