Primary mesenchymal chondrosarcoma of the lung.

Mesenchymal chondrosarcoma has been well documented in the somatic soft tissue and bone. It is a rare subtype of chondrosarcoma characterized by the presence of islands of chondroid or by less osteoid tissue enmeshed within dense sheets of primitive small blue mesenchymal cells with hemangiopericytoma-like vessels, or by both. The vast majority of previously published pulmonary mesenchymal chondrosarcoma was metastatic. To the best of our knowledge, only one case of primary pulmonary mesenchymal chondrosarcoma has been described in the literature. Herein, we report the second case of primary mesenchymal chondrosarcoma of the lung and emphasize that biopsy may yield only nonspecific small blue cells, whereas a detailed evaluation of the resected specimen allows definite diagnosis of this rare lung tumor.