High-Grade Myxoid Spindle Cell Sarcoma of the Pleura

Abstract

Spindle cell sarcomas arise from primitive mesenchymal cells and have a broad spectrum of histological differentiation. They are rare but diversified in presentation, as well as outcomes. A small group of these rare malignant tumors presents spindle cells embedded in an abundant myxoid stromal matrix. The myxoid spindle cell sarcomas mostly involve the extremities, and their occurrence in the pleura is rare. The distinguishing of the various sarcomas within the group of myxoid spindle cell sarcomas is complicated. We report a case of high-grade myxoid spindle cell sarcoma arising from the pleura presenting with massive pleural effusion. Thoracoscopic inspection of the pleural cavity showed a fleshy and gelatinous formless mass. Surgical removal provided only temporary relief. The tumor re-grew rapidly and did not respond to salvage radiotherapy. The histological patterns and the immunohistochemical studies suggested a high-grade myxoid spindle cell sarcoma. However, the features of the tumor presented here were distinct from those of the published differential diagnoses of myxoid spindle cell sarcoma. The literature was reviewed and the differential diagnoses of the presented case explored.