Pathology of Thymic Epithelial Tumors

摘要: It is well known that the thymic epithelial neoplasms have to be distinguished from nonepithelial tumors, mainly malignant lymphomas, of thymus (CASTLEMAN 1955; BERNATZ et al. 1961; LATTES 1962; LEGG and BRADY 1965; ROSAI LEVINE 1976; SALYER EGGLESTON 1976). However, epithelium considered give rise both thymoma carcinoma, i.e., morphologically biologically different neoplasms. Thymomas are characterized by cells (ECs) sharing morphological features with their normal counterparts a variable amount lymphoid infiltration similar thymus. They either show benign course or aggressive growth in adjacent tissues. Thymic carcinomas obviously cytologically appear as almost pure growths (LEVINE 1978). The wide range expressions carcinoma has been interpreted consequence various differentiation pathways pluripotential stem cell endodermal origin (SNOVER 1982).