Pulmonary carcinosarcoma: a case report.

Pulmonary carcinosarcoma, belonging to sarcomatoid carcinomas, is a quite rare tumor that contains both malignant epithelial and mesenchymal elements. This tumor has different phenotypic characteristics and clinical course compared to non-small cell lung tumors. A case diagnosed as carcinosarcoma is presented and its clinical and pathological features and the differential diagnosis are discussed. The case was a 74-year-old male admitted with shortness of breath and cough. The chest x-ray showed a left lung mass and a bronchoscopic examination was performed. Histopathological examination of the bronchoscopic biopsy showed necrosis and a malignant tumor consisting of diffuse infiltrative anaplastic cells. Surgery was performed and the case was diagnosed as carcinosarcoma in the resection material. Pulmonary carcinosarcoma is a rare lung tumor. Determination of tumoral cells and performing advanced investigations in resection material seem to be relatively easier than in small biopsies. However, this type of tumor can be encountered in small biopsy materials as in the presented case and should be kept in mind in relation to the differential diagnosis as small tissues can have only one, particularly mesenchymal, tumoral component.