Tissue microarray: A valuable method in diagnosis and prognosis of hematological malignances

BACKGROUND: The novel technology of tissue microarray (TMA) allows rapid and cost-effective analysis of hundreds of markers on the same set of specimens. Limited amount of tissue that could be analyzed and problem of tissue heterogeneity, are the major drawbacks of TMA technique for immunohistochemical characterization of lymphomas. METHODS: In this paper 65 cases of lymphomas were analyzed using TMA with following panel of antibodies: BOB1, Oct2, Bcl2, Bcl6, CD20, CD21, CD23, CD3, CD5, CD10, CD43, CD79a, CD138, Cyclin D1, Ki67, MUM1, Pax5, p53. RESULTS: In 14 patients with diffuse large B-cell lymphoma (DLBCL), 5 were classified as germinative center and 3 as non-germinative center cases according to the Bcl6, CD10, and MUM1 positivity. Other 2 patients were identified as T cell rich B cell lymphoma based on morphology and Oct2 and BOB1 positivity of pleomorphic B lymphocytes. DLBCL with Bcl6+ immunophenotype had better overall survival than Bcl6- cases. All cases of classic mantle cell lymphoma had significantly lower Ki-67 proliferation index than blastoid subtypes. There were 14 cases of chronic lymphocytic leukemia/small cell lymphocytic lymphoma, 6 cases with follicular lymphoma, 5 cases of marginal zone lymphoma, and 7 cases of lymphoplazmacitoid lymphoma. In the indolent lymphoma group, survival of patients with p53+/- was poorer comparing to p53- group. CONCLUSION: We conclude that TMA technique is a valuable method in diagnosis and prognosis of lymphomas, which are considered very heterogeneous group of hematological neoplasms.