Case 8
History:
28 year old male with swelling of the plantar aspect of the foot
Findings:
Axial CT of the foot showing a heterogenous plantar soft tissue lesion. T2 shows the lesion to be heterogenous with areas of hypointensity signal. The lesion enhances heterogenously.
Diagnosis:
Synovial sarcoma
Discussion:
Synovial sarcoma is a rare tumor that constitutes approximately 10 percent of all soft tissue sarcomas. The lesions most commonly occur in the second and fourth decades of life but may be seen in all age groups. The name synovial sarcoma originates from the similarity of the cells with synovial cells which line the surface of joints. Lesions are typically located in tendons and bursae in close proximity to joints. They generally involve the lower extremities, but may be seen in the upper extremities, head and neck region, the wall of the abdomen.
The lesion usually shows well-defined contours. Calcifications may be seen in 30 percent of cases. Adjacent bone destruction is present in 20 percent of cases. On CT scan the lesion shows density similar to muscles. CT depicts bony involvement and presence of calcifications. On MRI sarcoma shows isointense signals relative to muscle tissue on T1-weighted MR images and hypo- or hyperintense signals on T2-weighted MR images.
