Plasma cell myeloma marrow diagnosis including morphologic and phenotypic features.

This article emphasizes both the morphologic and phenotypic features of the bone marrow in plasma cell myeloma. It details the morphologic features of both trephine biopsies and marrow aspirations. It emphasizes the salient phenotypic features of marrow myeloma cells, in contrast with normal plasma cells. The myeloma cell phenotype is discussed from the perspective of both tissue section immunohistochemistry (IHC) and flow cytometry (FACS analysis). The specific criteria for myeloma diagnosis are discussed and illustrated in Figures 1-12. Finally, the emphasis is on the key morphologic and phenotypic diagnostic criteria of each of the plasma cell neoplasms.