Case Slide No.:
CRUSH PREP. with MARROW SMEAR:
In this field, note the following : 1) a trinucleate myeloma cell, 2) a near-naked nucleus (possibly that of a myeloma cell – see black arrow ), 3) a basophilic normoblast (see red arrow) and 4) a myeloma cell with a bizarre nuclear proboscis (above and immediately to the right of dead center).
In a review of 52 cases of . IgM myeloma published in 1990, mean serum IgM was 3.0 gm/dL. Kappa was the dominant light chain in 80% of cases. The incidence of IgM myeloma was 0.5% of all myelomas. It may be difficult to distinguish between IgM myeloma and Waldenstrom macroglobulinemia. (IgM myeloma : 6 cases and a review of the literature (De Gramont A , Grosbois B, Michaux JL et al. Rev Med Interne 1990 11(1) : 13-8). Not one of the morphologic features shown in this case is pathognomic of IgM myeloma or indeed of any other subtype of the disease.