Giant primary mesenchymal chondrosarcoma of the lung: case report and review of literature.

Mesenchymal chondrosarcoma, a rare malignant tumor, was predominantly occurring in the bone and may involve somatic soft tissue but it is extremely rare in the lung.We report the case of a 20-year-old female who presented with a 2-month history of irritant nonproductive cough and chest pain. The histopathologic examination revealed the tumor composed of atypical undifferentiated small cells and islands of matured chondroid matrix typically presented as bimorphic appearances. Immunohistochemical examination revealed that the tumor cells were positive for vimentin and CD99 for all components, and to S-100 limited to the areas of cartilage. In addition, previously reported cases of primary lung mesenchymal chondrosarcoma were reviewed, and the relevant clinical knowledge regarding its clinical manifestations, diagnosis, and treatment were discussed.