Aggressive primary plasma cell leukemia with skin manifestations, trisomy 8 and molecular oligoclonal features

Plasma cell leukemia (PCL) is a very rare variant of multiple myeloma (MM) occurring in about 2% of newly diagnosed patients. Plasma cell leukemia may develop during the course of MM (secondary PCL) or it can occur without any prior sign of MM (primary PCL). We report a case of aggressive primary PCL with unusual clinical, cytogenetic and molecular features. A 36-year-old male patient was first seen because of fever and bone pain. On the skin of his chest, back, abdomen, and palpebras, there were nodular infiltrations resembling urticaria. White blood cell count was 10.8 x 10(9)/l with 41% plasmacytes. Bone marrow aspiration was hypercellular, 93.5% of cells were atypical plasmacytes and plasmablasts. The cytogenetic analysis of G-banded chromosomes in bone marrow cells yielded the trisomy 8. The skin biopsy specimen showed intensive infiltrates of uninucleated blastic cells similar to those found in the bone marrow. Immunophenotyping of bone marrow and skin neoplastic cells showed CD45+, CD45Ro+, CD68+, CD38+ and cytoplasmic kappa light chain +. The neoplastic cells stained negatively for lambda light chain, CD3, CD20, CD30, EMA, CD15, CD34, CD56 and factor VIII. The pattern of IgL genes rearrangement in the bone marrow aspirate, peripheral blood mononuclear cells, and skin specimens was examined by PCR analysis. All studied specimens showed three different IgK gene configurations suggesting that the neoplastic cells originated as a result of oligoclonal lymphoproliferation process. The patient received two courses of VAD (vincristine, doxorubicin, dexamethasone) without improvement and three courses of CHOP with only temporary stabilization of the disease. He died 5 months after the diagnosis of PCL because of disease progression and pneumonia.