Pleomorphic and Desmoplastic Malignant Mesotheliomas and a Malignant Mesothelioma with Osseous and Cartilaginous Differentiation: Case Reports - Abstract
We herein present three autopsy cases of unusual malignant mesotheliomas with peculiar histological features.
Case 1: The patient was a 69-year-old female. The tumor encased the entire left lung, and metastasized to multiple organs. Histologically, more than 80% of the tumor was occupied by large discohesive pleomorphic cells with single or multiple irregular nuclei, and the remaining part of the tumor showed a tubulopapillary and sarcomatoid pattern. The tumor of this case was pleomorphic mesothelioma.
Case 2: The patient was a 64-year-old male. A pleural biopsy disclosed malignant spindle cells, but a definitive diagnosis was not obtained until his death. The tumor encased the right lung invading the right chest wall, and had metastasized to multiple organs. Histologically, the tumor consisted of neoplastic spindle cells with foci of osseous and cartilaginous differentiations. The tumor of this case was a sarcomatoid
mesothelioma with osseous and cartilaginous differentiations.
Case 3: The patient was a 75-year-old male, who had pleural effusion in the right thoracic cavity. A definitive diagnosis was not obtained by the cytological examination of the effusion or the tumor biopsy. During autopsy, it was found that the tumor encased the right lung, invading the diaphragm. Metastases were seen in the liver. The histological examination showed that the tumor was a desmoplastic mesothelioma.