Primary Plasma Cell Leukemia: Clinical, Immunophenotypic, DNA Ploidy, and Cytogenetic Characteristics

Abstract

We report on a series of 26 patients diagnosed with primary (de novo) plasma cell (PC) leukemia (PCL) in whom we analyzed the clinicobiologic characteristics of the disease together with the immunophenotype, DNA cell content, proliferative index, and numeric chromosomal aberrations of the neoplastic PC, and compared them with 664 multiple myeloma (MM) patients at diagnosis. The median age, sex ratio, and bone lesion extension were similar, but PCL cases displayed a higher prevalence of clinical stage III, extramedullary involvement, and Bence Jones cases, with fewer IgA cases than for MM patients. In addition, according to several prognostic indicators (β2-microglobulin serum level, proportion of S-phase PCs, proteinuria, calcium serum level, lactate dehydrogenase [LDH] and renal function), the incidence of adverse prognostic factors was significantly higher in PCL versus MM. Immunophenotypic expression was similar for CD38, CD138, CD2, CD3, CD16, CD10, CD13, and CD15, but PCL differed from MM in the expression of CD56, CD9 HLA-DR, CD117, and CD20 antigens. Twenty-two PCL cases were diploid and one was hypodiploid, while most MM cases (57%) showed DNA hyperdiploidy. With the fluorescent in situ hydridization (FISH) technique, 12 of 13 PCL cases displayed the numeric aberrations, −13 (86%), ±1 (57%), +18 (43%), and −X in women (25%), but they lacked several numeric aberrations usually found in MM such as +3, +6, +9, +11, and +15. PCL cases had a lower overall response to therapy than MM cases (38% v 63%, P = .01332). Among PCL patients, a trend for a worse response was observed in cases treated with melphalan and prednisone (MP) versus polychemotherapy. Overall survival was significantly worse in PCL versus MM patients (8 v 36 months,P < .0001), but it was significantly better in PCL patients treated with polychemotherapy versus MP (18 v 3 months,P = .0137). By contrast, MM patients did not show significant differences in overall survival according to the treatment used, MP or polychemotherapy. Ten variables seemed to predict survival in PCL patients, but only the β2-microglobulin level and S-phase PCs retained an independent value in multivariate analysis. In summary, our study illustrates that PCs from PCL display singular phenotypic, DNA cell content, and cytogenetic characteristics that lead to a different disease evolution versus MM.

Atypical blast morphology of primary plasma cell leukemia with renal involvement and plasmablasts in urine

“…In PCL proliferation of normal bone marrow cells (residual cells in S phase) is markedly blunted compared to malignant PCs. 3 Second, our patient was 79 years old, which is significantly older than in other cases. In nearly all reported cases, the patients were younger than 65 years, which is common feature of pPCL.…”

“…2 In 15-23% of cases PCL is associated with extramedullary extension of the disease and various tissue infiltrations, which contributes to impairment of organ function. 1,3 PCL is an aggressive disease with fulminant course and poor prognosis. Median overall survival is 7-11 months for pPCL and 2-7 months for sPCL.…”

Multiple primary cutaneous plasmacytoma a decade after a nasal solitary extramedullary plasmacytoma: a puzzling case

“…Monoclonal gammopathies constitute a heterogeneous group of diseases characterized by the presence of a single clone proliferation of plasma cells, typically producing a monoclonal immunoglobulin. These entities include a wide spectrum of disorders, from monoclonal gammopathy of uncertain significance to multiple myeloma, plasma cell leukemia, solitary bone plasmacytoma (SBP), or extramedullary plasmacytoma (EMP) [3,5].…”

Primary plasma cell leukemia: A case report and review of the literature

“…pPCL has an aggressive clinical course given its tendency to invade extramedullary sites (lymphadenopathy, hepatosplenomegaly, pleural effusion, skin, and central nervous system involvement) in up to 20% of patients. 9,11,12 Higher prevalence of elevated lactate dehydrogenase (LDH) (> = 460 U/L, 48% vs 9% in MM), anemia (Hgb < 8.5 g/ dL, 54% vs 31% in MM), thrombocytopenia (platelets <100 × 10 9 /L, 48% vs 9% in MM), beta-2 microglobulin (> = 6 mg/L, 65% vs 27% in MM), hypoalbuminemia, hypercalcemia (serum calcium > = 11 mg/dL, 48% vs 20% in MM), and renal impairment (serum creatinine > = 2 mg/dL, 44% vs 21% in MM) is observed in pPCL. 11 Additionally, osteolytic lesions are less common in pPCL (35% vs 81% of MM and 53% of sPCL).…”

“…Cytogenetic abnormalities are seen in 70% of pPCL and 100% of sPCL. 15 Multiparametric flow cytometry shows increased prevalence of CD20, CD44, CD45, CD19, and CD23 and lower CD9, CD56, CD117, and HLA-DR. 11,16 CD56 is a neuronal cell adhesion molecule that anchors plasma cells to the bone marrow stroma, preventing their migration to extramedullary sites. 17 Higher frequencies of t(4;14), t(11;14) and t(14;16) were observed in pPCL.…”