Determinação da expressão da molécula de adesão CD56 em plasmócitos no mieloma múltiplo através de estudo imuno-histoquímico CD56 adhesion molecule expression by plasma cells in multiple myeloma immunohistochemistry

Abstract The role of adhesion molecules in the physiopathologyof multiple myeloma has been the target of many studiesover the last years. The CD56 expression by neoplasticplasma cells is related to a less aggressive clinical course,and its loss is described in plasma cell leukemia. Theevaluation of the CD56 expression may be obtained byflow cytometry, with positivity in 55% to 78% of cases. Inthis study, we verified the CD56 expression by plasma cellsin bone marrow of myeloma patients usingimmunohistochemistry in samples obtained at diagnosis.We analyzed bone marrow of 20 myeloma patients andperformed immunohistochemistry to determine theexpression of the kappa and lambda light chains and CD56by neoplastic plasma cells. The CD56 expression wasimportant in three samples, moderate in six, discrete infour and negative in seven. Immunohistochemistry wasvalid to determinate CD56 expression by neoplastic plas-ma cells in myeloma patients, giving similar results whencompared with flow cytometry. It was possible to evaluatethe variations in the CD 56 expression using this method.Rev. bras. hematol. hemoter. 2003;