COEXISTING UNDIFFERENTIATED THYMIC CARCINOMA AND THYMIC CARCINOID-TUMOR

Thymic carcinoma is an unusual neoplasm, and the undifferentiated type is rare. Thymic carcinoid is also rare. This report describes a patie nt with coexisting undifferentiated thymic carcinoma and a carcinoid t umor. Both lesions were completely excised. The carcinoid cells showed argyrophilic granules by Grimelius' method and immunoreactivity again st neuron-specific enolase, whereas the undifferentiated carcinoma cel ls were negative for argyrophilic stain and immunostaining against neu ron-specific enolase.