Presentation
Left medial thigh swelling of 2 months duration.
Patient Data
Left thigh medial inter-muscular well defined heterogeneous soft tissue lesion. The mass elicits heterogeneous signal with cystic and solid components. The cystic portion shows hemorrhagic components. The lesion displaces the adjacent muscles.
Morphological aggressive features of the lesion were suggestive of a neoplastic process (likely sarcoma).
Tru-cut biopsy of the lesion shows synovial sarcoma- monophasic type
Case Discussion
The aggressive features of the lesion with both solid and cystic components, and the hemorrhagic areas within the cystic component were suggestive of neoplastic process (likely soft tissue sarcoma).
Synovial sarcomas typically present in adolescents and young adults (15-40 years of age)
The presentation is most often with a slowly-enlarging soft tissue mass which may have been noted for some years and gives a false impression of a benign process.
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On MRI, the lesion appears heterogeneous on fluid-sensitive sequences secondary to areas of necrosis and cystic degeneration with very high signal, relatively high signal soft tissue components and areas of low signal intensity due to dystrophic calcifications and fibrotic bands.
- due to the high tendency of lesions to bleed, there might be areas of fluid-fluid levels known as "bowl of grapes" are seen in up to 10-25% of cases