Humans ; Thymoma/pathology* ; Thymus Neoplasms/pathology*

Child ; Choristoma ; Humans ; Male ; Neck ; pathology ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; Thymus Gland ; pathology ; Thymus Neoplasms

Adult ; Female ; Humans ; Sternum ; pathology ; surgery ; Thymus Neoplasms ; pathology ; surgery

A carcinoid tumor of the thymus combined with thymoma in a 62-year-old man is described. The mediastinal tumor had been present for 13 years and was associated with pure red cell aplasia. Carcinoid tumor occupied the central two-thirds of the tumor, consisting of nests and trabeculae of monotonous round cells, which ultrastructurally showed many intracytoplasmic dense-core granules. Typical spindle cell type thymoma surrounded the carcinoid area. Clinico-pathologic findings of this unique case suggested that the carcinoid tumor developed within a preexisting thymoma, illustrating a possibility of neuroendocrine differentiation of thymic epithelial cells.
Carcinoid Tumor/*pathology ; Humans ; Male ; Middle Aged ; Neoplasms, Multiple Primary/*pathology ; Thymoma/*pathology ; Thymus Neoplasms/*pathology

Cell Differentiation ; Choristoma ; pathology ; Humans ; Soft Tissue Neoplasms ; pathology ; Thymoma ; pathology ; Thymus Neoplasms ; pathology

Child ; Choristoma ; pathology ; Diagnosis, Differential ; Follow-Up Studies ; Humans ; Male ; Neoplasms, Glandular and Epithelial ; pathology ; Thymus Gland ; pathology ; Thymus Neoplasms ; pathology ; Thyroid Neoplasms ; pathology

Child ; Female ; Head and Neck Neoplasms ; diagnosis ; pathology ; surgery ; Humans ; Parathyroid Neoplasms ; diagnosis ; pathology ; surgery ; Thymus Gland ; pathology ; surgery ; Thymus Neoplasms ; diagnosis ; pathology ; surgery

Humans ; Pathology, Molecular ; Prognosis ; Thymoma ; diagnosis ; pathology ; Thymus Neoplasms ; diagnosis ; pathology

Carcinoma ; classification ; pathology ; Consensus ; Humans ; Thymoma ; classification ; pathology ; Thymus Neoplasms ; classification ; pathology ; World Health Organization

The objective of study was to investigate the origin and to classify the subtype of N-methyl-N-nitrosourea (MNU)-induced thymic lymphomas in mice. Histopathologic, immunohistochemical and ultrastructural studies were performed to analyze the pathological features of the neoplasms. The results showed that the thymus in all cases became totally replaced by sheets of cells of the lymphoid series. All the tumors coexpressed CD3 and TdT. Transmission electron microscopic study showed the plasma membranes of malignant lymphoma cells were smooth. The nuclear profiles were usually regular, with varying percentage of convoluted nuclei. Few cell organoids were observed in cytoplasm. In conclusion, all the MNU-induced tumor classified by histopathologic, immunohistochemical and ultrastructural studies as precursor lymphoblastic lymphoma that were unquestionably related to the thymus origin and T-cell lineage.
Animals ; Female ; Lymphoma ; chemically induced ; pathology ; ultrastructure ; Male ; Methylnitrosourea ; adverse effects ; Mice ; Mice, Inbred C57BL ; Thymus Gland ; pathology ; ultrastructure ; Thymus Neoplasms ; chemically induced ; pathology ; ultrastructure