Heterologous sarcomatoid pleural mesothelioma with osteosarcomatous differentiation: a report of autopsy case that accomplished trimodality therapy and review of the literature.

Heterologous mesothelioma is a very rare subtype of sarcomatoid mesothelioma characterized by the presence of malignant heterologous elements. A 69-year-old man with a strong history of asbestos exposure presented with a 5-cm mass in his chest wall, destroying the right 5th rib and spreading along the parietal pleura, on a CT. Biopsy revealed heterologous mesothelioma with osteosarcomatous elements, following which left extrapleural pneumonectomy was performed with combined resection of pericardium, hemidiaphragm, and 4th, 5th, and 6th costal segments.