Criteria of Kyle et al for plasma cell leukemia - both of the following:
(1) plasma cells > 20% of the differential count on the peripheral blood smear
(2) absolute plasma cell count > 2,000 per µL
Features:
(1) Most cases arise in patients with myeloma (secondary), but some cases may arise in the absence of myeloma (primary, de novo).
(2) It tends to occur more frequently in patients with light chain only, IgE, or IgD producing myelomas than in IgG or IgA myeloma.
(3) Monoclonal proteins and osteolytic lesions may be absent
Poor prognostic features:
(1) massive bone marrow replacement with anemia and thrombocytopenia
(2) hepatosplenomegaly and lymphadenopathy
(3) renal failure
