PAX5 and CD70 are expressed in thymic carcinoma but not in atypical thymoma (WHO type B3 thymoma): an immunohistochemical analysis of 60 cases.

Among the markers explored, only PAX5 and CD70 appear to be differentially expressed and are predominantly restricted to thymic carcinomas. Therefore, in small biopsy specimens and in resections in which the morphological features remain equivocal, application of these particular stains may facilitate separation of thymic carcinoma and atypical thymoma.