Residency Program - Case of the Month

Clinical history:

The patient is a 57 year old male who noted a "pop" in his right thigh while doing heavy labor activities. This was followed by mild to severe sharp, burning pain and dull aches. An X-ray of the right lower extremity showed a large soft tissue mass within the right anterior thigh. A follow-up MRI revealed a heterogeneous mass within the anterior thigh compartment measuring 10 x 9 x 12 cm.

Gross description:

A partially ossified, solid and cystic, ill-defined tumor was noted within the thigh measuring 21 x 17 x 11 cm. The cystic portions were filled with blood. The solid portions were firm and tan with areas of hemorrhage and ossification. (No gross photos available)

Immunohistochemical stains:

• CD31

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