[Classification and differential diagnosis of primary thymic tumors].

To make a diagnosis and a differential diagnosis of mediastinal tumors always encounters many difficulties. Differentially, the diagnostic spectrum includes a great number of histologically different tumor types. Routine light microscopic techniques are frequently insufficient for a tumor to be classified. This mainly applies to thymomas and malignant lymphomas. So tumor morphological diagnostic techniques have been improved year after year. Immunohistological techniques may further serve as a method of precision diagnosis of tumors. The application of these methods largely changes our logic and implies a close cooperation between diagnosis and therapy.