CASE 81: Clear Cell Sarcoma Located in the Knee

A patient presented with swelling on the outer side of the knee. Physical examination and radiological tests revealed a mass, and a needle biopsy revealed a soft tissue sarcoma. We performed surgery to remove the tumor with wide margins (including the proximal fibula) and close the resulting cavity with a gastrocnemius flap and skin graft, following a diagnosis and radiotherapy.

Preoperative examination: MRI shows an irregular, heterogeneous mass located on the outer side of the knee, surrounded by edema; PET scan reveals significantly increased activity.

During the operation: The clinical appearance of the mass, the incision line, the gastrocnemius flap, and the mass removed with the skin graft are shown.

Postoperative: Wound healing and proximal fibula resection are visible on X-ray.