title: Primary thymic carcinoma. An unusual case originating in a lymphocytic rich thymoma.
abstract: A case of thymic carcinoma arising within a lymphocyte rich thymoma is reported. The undifferentiated carcinoma contained cellular elements resembling choriocarcinoma but could be differentiated therefrom by positive staining for prekeratin antigen and an absence of staining for B-HCG antigen utilizing immunohistochemical techniques.
mesh_terms: D000328:Adult; D005260:Female; D006651:Histocytochemistry; D006801:Humans; D007124:Immunoenzyme Techniques; D007633:Keratins / Q000032:analysis; D008854:Microscopy, Electron; D011498:Protein Precursors / Q000032:analysis; D013945:Thymoma / Q000473:pathology*; D013953:Thymus Neoplasms / Q000473:pathology*
chemical_list: D011498:Protein Precursors; C004818:prekeratin; D007633:Keratins