Treatment of a patient with malignant mesothelioma with interferon-alpha 2 based on in vitro sensitivity tests.

The case of a 70-year-old patient with an epithelial mesothelioma is presented. The patient suffered from dyspnea due to a right-sided recurrent hemorrhagic effusion. Cytological analysis of the effusion revealed marked lymphocytosis and tumor cells, some of them multinucleated with prominent nucleoli. Open lung biopsy revealed nodular thickening of the diaphragmatic, visceral, and parietal pleura; histological examination of biopsies detected intravascular growth of tumor cells. Immunocytochemical characterization of cultured tumor cells and the biopsy specimens showed positive staining to vimentin and cytokeratin, but negative reaction with antibodies against epithelial membrane associated antigen, leukocyte common antigen, van Willebrand factor, and neurofilament. Hence, the tumor was classified as malignant mesothelioma. In vitro, interferon-alpha 2 produced a dose-dependent inhibition of proliferation in the cultured mesothelioma cells. Two weeks after initiation of interferon-alpha 2 treatment the patient improved and the pleural effusion vanished.