E2353. Tools for Sorting T1 Hypertense Soft Tissue Tumors
  1. Jinyong Bae; San Antonio Uniformed Services Health Education Consortium
  2. Samuel Madson; San Antonio Uniformed Services Health Education Consortium
  3. David Kephart; San Antonio Uniformed Services Health Education Consortium
Motivated by concern about possible malignancy, soft-tissue lesions are a common reason for visiting a physician's office and for being referred to the radiology department. The American Cancer Society estimated that in 2022, there would be 13,190 new cases of soft-tissue sarcoma’s in the United States and 5130 deaths caused by soft-tissue sarcomas. Histologic evaluation definitely establishes the diagnosis; however, routine biopsy of all soft-tissue lesions is impractical and comes with undesirable risk to patients. Although most soft-tissue lesions are benign, an astute radiologist should be able to discern suspicious imaging characteristics. With knowledge of MRI T1 weighted (T1WI) imaging features, a radiologist may further narrow the differential and coordinate for a timely biopsy, consultation with orthopedic surgeons, thereby limiting delay of care.

Educational Goals / Teaching Points
This exhibit will present a systematic approach to soft-tissue masses aiding the reader to differentiate between benign and malignant masses. We will review both common and rare causes for hyperintense T1WI soft-tissue tumors, not limited to adipocytic tumors, undifferentiated small round cell sarcomas, melanin-containing and tumors of uncertain differentiation. We will also discuss specific hyperintense T1WI soft-tissue sarcomas with respect to MRI characteristics and how to preclude haplessly tilting toward a benign pathway.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
Differentials based on imaging morphology such as internal heterogeneity, calcification, diffusion, macroscopic fat, blood, and contrast enhancement will be reviewed and pictorially demonstrated. Cases of benign-appearing homogeneous, lobulated, and well-circumscribed lesions but found to be aggressive malignant T1 hyperintense soft-tissue sarcoma will be presented.

Radiologists should be on the lookout for benign-appearing but malignant sarcomas. T1 hyperintense soft-tissue sarcomas are less common than T1 hypointense soft-tissue sarcomas and because of this, often not well-studied or dismissed as trivial knowledge. The ability to recognize these lesions will guide the clinician in further workup of the mass.