© American Society for Clinical Pathology Flow Cytometry in the Differential Diagnosis of Lymphocyte-Rich Thymoma From Precursor T-Cell

We compared the antigen expression profile of thymocytes in lymphocyte-rich thymoma with that of precursor T-cell acute lymphoblastic leukemia/ lymphoblastic lymphoma (T-cell ALL/LBL) cells using 4-color flow cytometry. In all 15 thymoma cases, the thymocytes demonstrated 3 distinct subpopulations. The least mature cells (double-negative) expressed low-density CD2 and CD5, high-density CD7, CD10, CD34, and heterogeneous CD4 and CD8. They had the lowest density CD45 expression and were surface CD3–. The immature cells (double-positive) expresse