Simultaneous presentation of plasma cell and monocytic leukemia with a subacute clinical course

A rare case of simultaneous presentation of monocytic and plasma cell leukemia is reported. Cytochemistry, transmission and scanning electron microscopy confirmed the presence of a dual population consisting of monoblasts and plasma cells. Monoblasts contained nonspecific esterases, secreted lysozyme and showed dense bodies and surface ruffles under the scanning electron microscope, while the plasma cells secreted IgG kappa paraprotein, contained rough endoplasmic reticulum, and showed surface blebs with microvilli. Another unusual feature of this case was the relatively chronic course of the disease, lasting 15 months after initial diagnosis.