How I treat plasma cell leukemia

Plasma Cell Leukemia Presenting as a Chest Wall Mass: A Case Report

Plasma cell leukemia (PCL) is an uncommon neoplasm of plasma cells, with an aggressive clinical course and poor outcome, even with current standard of care. It can occur either de novo (primary PCL) or as a progression of multiple myeloma (MM). This disease has unique diagnostic criteria but certain genetic markers and clinical features may overlap with MM. Due to the low prevalence of PCL, guidelines on its management are extrapolated from the management of MM and based on small retrospective studies and cases reports/series. We present an interesting case of PCL in a middle-aged African-American male, who was diagnosed incidentally after chest wall imaging for an unrelated complaint. The diagnostic approach, management and outcomes of PCL are discussed.

Bortezomib, Doxorubicin, Cyclophosphamide, Dexamethasone Induction Followed by Stem Cell Transplantation for Primary Plasma Cell Leukemia: A Prospective Phase II Study of the Intergroupe Francophone du Myélome

PURPOSE

Primary plasma cell leukemia (pPCL) is a rare and aggressive malignancy with a poor prognosis. With conventional chemotherapy, patients typically die within 1 year. In all but one of the retrospective studies reported to date, bortezomib and lenalidomide seem to improve survival. We conducted a prospective phase II trial in patients with pPCL to assess the efficacy of an alternate regimen that combines standard chemotherapy, a proteasome inhibitor, and high-dose melphalan and autologous stem cell transplantation (HDM/ASCT) followed by either allogeneic transplantation or bortezomib/lenalidomide maintenance.

PATIENTS AND METHODS

Patients 70 years old and younger with newly diagnosed pPCL received four alternating cycles of bortezomib, dexamethasone plus doxorubicin or cyclophosphamide. Peripheral blood stem cells were collected from responding patients with < 1% of circulating plasma cells before HDM/ASCT. As consolidation, young patients received a reduced-intensity conditioning allograft, whereas the remaining patients underwent a second HDM/ASCT followed by 1 year of bortezomib, lenalidomide, dexamethasone. The primary end point was progression-free survival (PFS).

RESULTS

Forty patients (median age, 57 years; range, 27 to 71 years) were enrolled. The median follow-up was 28.7 months. In the intention-to-treat analysis, the median PFS and overall survival were 15.1 (95% CI, 8.4; -) and 36.3 (95% CI, 25.6; -) months, respectively. The overall response rate to induction was 69%. One patient underwent a syngeneic allograft and 25 HDM/ASCT (16 of whom subsequently received a reduced-intensity conditioning allograft and seven a second ASCT followed by maintenance).

CONCLUSION

In this prospective trial in patients with pPCL, we show that bortezomib, dexamethasone plus doxorubicin or cyclophosphamide induction followed by transplantation induces high response rates and appears to significantly improve PFS.

Plasma cell leukemia in North India: retrospective analysis of a distinct clinicohematological entity from a tertiary care center and review of literature

Background

Plasma cell leukemia (PCL) is a rare and aggressive plasma cell neoplasm. In PCL, clonal plasma cells comprise ≥20% of the peripheral blood (PB) leukocytes and/or the absolute clonal PB plasma cell count is ≥2×10⁹/L. Primary PCL (PPCL) originates de novo, whereas, secondary PCL (SPCL) evolves from pre-existing multiple myeloma.

Methods

Clinicohematological features, immunophenotypic profile, and survival of PCL patients were analyzed retrospectively.

Results

Between January 2007 and December 2014, ten PPCL and four SPCL patients were investigated (8 PPCLs and 3 SPCLs had complete clinical data). All were North Indians, sharing common geography and ethnicity. Our cohort showed less frequent renal failure, more frequent hepatomegaly, and non-secretory type disease. In contrast to western literature, flow cytometric immunophenotyping of our cohort revealed altered expression of CD138 (67%), CD56 (33%), and CD20 (0%). With novel therapeutic agents, these PPCL patients had a median overall survival of 15 months.

Conclusion

We highlight that our PPCL patients from North India had distinct clinicohematological and immunophenotypic profiles. The significance of our findings must be tested in a larger patient cohort and must be supported by molecular and cytogenetic investigations to unmask possible significant effects on pathogenesis.

Immunoglobulin D Multiple Myeloma, Plasma Cell Leukemia and Chronic Myelogenous Leukemia in a Single Patient Treated Simultaneously with Lenalidomide, Bortezomib, Dexamethasone and Imatinib

Multiple myeloma (MM) is a neoplastic lymphoproliferative disorder characterized by uncontrolled monoclonal plasma cell proliferation. Among different isotypes of MM, immunoglobulin D (IgD) MM is very rare, representing only 1 to 2% of all isotypes. Chronic myelogenous leukemia (CML) is a neoplastic myeloproliferative disorder of pluripotent hematopoietic stem cell, which is characterized by the uncontrolled proliferation of myeloid cells. An 88-year-old male was diagnosed simultaneously with IgD kappa MM and CML. A distinctive feature in this patient was the progression to plasma cell leukemia without any symptomatic myeloma stage. He was treated simultaneously with lenalidomide, bortezomib and imatinib. Synchronous occurrence of these rare hematological malignancies in a single patient is an exceedingly rare event. Multiple hypotheses to explain co-occurrence of CML and MM have been proposed; however, the exact etiological molecular pathophysiology remains elusive.

Monoclonal antibodies targeting CD38 in hematological malignancies and beyond

CD38 is a multifunctional cell surface protein that has receptor as well as enzyme functions. The protein is generally expressed at low levels on various hematological and solid tissues, while plasma cells express particularly high levels of CD38. The protein is also expressed in a subset of hematological tumors, and shows especially broad and high expression levels in plasma cell tumors such as multiple myeloma (MM). Together, this triggered the development of various therapeutic CD38 antibodies, including daratumumab, isatuximab, and MOR202. Daratumumab binds a unique CD38 epitope and showed strong anti-tumor activity in preclinical models. The antibody engages diverse mechanisms of action, including complement-dependent cytotoxicity, antibody-dependent cellular cytotoxicity, antibody-dependent cellular phagocytosis, programmed cell death, modulation of enzymatic activity, and immunomodulatory activity. CD38-targeting antibodies have a favorable toxicity profile in patients, and early clinical data show a marked activity in MM, while studies in other hematological malignancies are ongoing. Daratumumab has single agent activity and a limited toxicity profile, allowing favorable combination therapies with existing as well as emerging therapies, which are currently evaluated in the clinic. Finally, CD38 antibodies may have a role in the treatment of diseases beyond hematological malignancies, including solid tumors and antibody-mediated autoimmune diseases.

How I treat extramedullary myeloma

Extramedullary myeloma (EMM) is defined by the presence of plasma cells (PCs) outside the bone marrow in a patient with multiple myeloma (MM). Using sensitive imaging techniques including magnetic resonance imaging and positron emission tomography/computed tomography, EMM may be found in up to 30% of MM patients across the overall disease course. The molecular mechanisms underlying the hematogenous spread of PCs outside the bone marrow are only partially known and involve hypoxia and an altered expression of adhesion molecules. Extramedullary disease is associated with adverse prognostic factors (ie, high lactate dehydrogenase level, 17p deletion, and high-risk gene expression profile). The prognosis of EMM is poor, and the median overall survival of patients who experience an extramedullary relapse is <6 months. The adverse prognosis is less pronounced in patients with bone-related plasmacytomas than in those with hematogenous EMM. EMM patients should be considered as having high-risk myeloma and treated accordingly. However, EMM clinical situations are extraordinarily heterogeneous, and their management is particularly challenging. In the present review, a case-and-comment format is used to describe our approach to the management of EMM.

Primary plasma cell leukaemia in a 22-year-old woman: A case report

Introduction

Primary plasma cell leukaemia is a rare and highly aggressive disease that is commonly diagnosed a decade earlier than multiple myeloma, at a median age of 55 years. However, it has also been described in younger patients, as documented in this case report. It often presents with hepatosplenomegaly and lymphadenopathy, whilst the presence of bony lesions are less-commonly seen when compared to multiple myeloma.

Case presentation

This report describes the case of a young woman who presented with symptoms of anaemia and a history of menorrhagia. On further careful examination, she was found to have additional signs and symptoms and was later diagnosed with primary plasma cell leukaemia.

Management and outcome

On admission, the patient received supportive care measures, including blood products. At diagnosis, a specific chemotherapy regimen was commenced; however, this failed to induce remission. The decision to continue with supportive care only was made and the patient died seven months later.

Discussion

This case study is presented because of its rarity, the young age of the patient at presentation and the unusual clinical and laboratory findings. Persistent anaemia unresponsive to standard treatment should raise the index of suspicion and further investigations directed to exclude malignancies should be considered.

Primary Plasma Cell Leukemia in the Era of Novel Agents: A Multicenter Study of the Japanese Society of Myeloma

We investigated the treatment and outcome of Japanese patients with primary plasma cell leukemia (pPCL) in the era of novel agents and analyzed the risk factors affecting survival. Among 3,318 patients with symptomatic multiple myeloma (MM), 38 patients were diagnosed with pPCL. The median overall survival (OS) of the pPCL patients was 2.85 years, which was significantly extended compared with that in previous reports. The proportion of patients treated with novel agents was 61%. The OS of the patients treated with novel agents was significantly extended compared with that of patients treated without novel agents according to the generalized Wilcoxon test (2.85 vs. 1.16 years, p = 0.049). This statistical finding suggests that treatment with novel agents could have prevented early death in the patients with pPCL. Age was the only statistically significant prognostic factor associated with an inferior OS (hazard ratio 4.57). Five patients received maintenance therapy with novel agents, and their OS tended to be longer than that of the other patients without maintenance (4.45 vs. 2.85 years). Unlike MM, OS for pPCL has not been improved significantly over the last decade, especially in elderly patients. Therefore, it is important to establish the treatment strategy, particularly after induction treatment.

Molecular Classification and Pharmacogenetics of Primary Plasma Cell Leukemia: An Initial Approach toward Precision Medicine

Primary plasma cell leukemia (pPCL) is a rare and aggressive variant of multiple myeloma (MM) which may represent a valid model for high-risk MM. This disease is associated with a very poor prognosis, and unfortunately, it has not significantly improved during the last three decades. New high-throughput technologies have allowed a better understanding of the molecular basis of this disease and moved toward risk stratification, providing insights for targeted therapy studies. This knowledge, added to the pharmacogenetic profile of new and old agents in the analysis of efficacy and safety, could contribute to help clinical decisions move toward a precision medicine and a better clinical outcome for these patients. In this review, we describe the available literature concerning the genomic characterization and pharmacogenetics of plasma cell leukemia (PCL).

Localized Relapse of Primary Plasma Cell Leukaemia in the Central Nervous System

Primary plasma cell leukaemia (pPCL) is a rare and aggressive form of plasma cell malignancies with a very poor prognosis. Compared to other plasma cell malignancies the tendency to extramedullary spread is increased; however central nervous system (CNS) involvement is rare and only reported in few cases. We report the case of a 61-year-old man who was diagnosed with pPCL and achieved a complete remission after autologous stem cell transplantation but had a relapse in the CNS without systemic disease.

Plasma cell leukemia: Clinicopathologic, immunophenotypic and cytogenetic characteristics of 4 cases

Plasma cell leukemia (PCL) is a rare hematologic malignancy with very poor outcome. It is defined by the presence of >2 × 10(9)/L plasma cells or >20% plasmacytosis of the differential white cell count in the peripheral blood. Primary PCL is first diagnosed in the leukemic phase, while secondary PCL corresponds to the leukemic transformation of a previously diagnosed multiple myeloma (MM). The incidence of PCL ranges between 2-4% of patients with MM and 0.9% of patients with acute leukemia. In this case series, we describe the clinicopathologic, immunophenotypic, and cytogenetic findings of four patients diagnosed with PCL within a ten-year period (2002-2012) at King Faisal Specialist Hospital and Research Centre (General Organization), Riyadh, Saudi Arabia.

Primary plasma cell leukemia presenting as a thoracic mass

Primary Plasma cell leukaemia (pPCL) is a rare plasma cell (PC) malignancy. The strict criteria for the diagnosis is an absolute PC number greater 2 × 10(9)/L or a plasmocytosis accounting for > 20% of the differential white cell count that does not arise from a pre-existing multiple myeloma. pPCL was associated with aggressive clinic-biological features. Primary Plasma cell leukaemia is more characterised by an extra medullar involvement such as hepatomegaly, splenomegaly, lymphadenopathy, lepto-meningeal infiltration or extramedullary plasmocytomas. The prognosis of pPCL is very poor. We report the case of a fifty eight year-old man directed to the haematology department for diagnosis of pPCL revealed by a thoracic plasmocytomas mimicking a thoracic neoplasm. The patient received chemotherapy including a classic treatment for multiple myeloma but developed a pulmonary embolism. This case illustrates an uncommon presentation of pPCL the difficulty treating by multiple myeloma chemotherapy.

Oral lesion as unusual first manifestation of multiple myeloma: case reports and review of the literature

Extramedullary plasmacytoma (EMP) and solitary bone plasmacytoma (SBP) represent a disease continuum through a multistage process of cell differentiation, survival, proliferation, and dissemination, strictly related to multiple myeloma (MM), the second most common hematological malignancy. Herein, we report two cases of recurrent oral plasmacytoma progressed to MM, in which the first clinical sign of a more widespread disease was limited to the mouth. Based on our experience, we recommend a strict workup for the differential diagnosis between EMP, SBP, and MM for patients with oral plasmacytoma, including radiological exam of the skeleton, magnetic resonance imaging (MRI) of the bone, and positive emission tomography (FDG-PET). MRI and possibly PET can all be used to more sensitively detect EM plasmacytoma sites.

Plasma cell leukemia: A case series from South India with emphasis on rarer variants

Plasma cell leukemia (PCL) is a rare and aggressive variant of plasma cell dyscrasia. They occur de novo (primary) or as a late manifestation of multiple myeloma (secondary). Patients present with anemia, thrombocytopenia, renal failure, organomegaly and extramedullary manifestations. We are presenting this series as it is the second largest series from India (16) with 4 young cases (under 40 years of age), more number of female patients and two having ‘hairy cell’ morphology. It is recommended that techniques like immunophenotyping and protein electrophoresis be performed, whenever the morphology is not characteristic of plasma cells.

A case of secondary plasma cell leukemia resistant to novel agents, in which stringent complete remission was achieved and maintained for a long period of time after VAD therapy and tandem autologous transplantation

A 61-year-old woman was diagnosed in June 2011 as having immunoglobulin G (IgG) ĸ-type multiple myeloma (MM), stage II, according to the International Staging System (ISS). Chromosome analysis showed a complex karyotype, including t(11;14) and del 13q. Analysis of the cell surface markers revealed that the cells were positive for mature plasma cell-1 (MPC-1), and negative for cluster of differentiation (CD) 45 and CD49e, suggestive of an intermediate level of maturity of the cells. The disease was refractory to bortezomib-dexamethasone (BD) therapy and progressed to plasma cell leukemia despite the treatment. Treatment was therefore switched to lenalidomide-dexamethasone (RD) therapy, however, the condition again proved to be refractory to this therapy. A partial response (PR) was achieved with vincristine-doxorubicin-dexamethasone (VAD) therapy. The residual plasma cells became CD45-positive, suggesting a change of the cells from an intermediate level of maturity to mature cells. In December, autologous peripheral blood stem cell transplantation (Auto-PBSCT) was performed after high-dose melphalan therapy (melphalan 200 mg/m(2)) as pretreatment. PR was observed and a second Auto-PBSCT was performed in July 2012. Stringent complete remission (sCR) has been maintained for 2 years since, without any further treatment. This is the first reported case of secondary plasma cell leukemia (sPCL) resistant to new drugs that was successfully treated by high-dose melphalan in combination with VAD therapy and Auto-PBSCT.

European Myeloma Network recommendations on the evaluation and treatment of newly diagnosed patients with multiple myeloma

Multiple myeloma management has undergone profound changes in the past thanks to advances in our understanding of the disease biology and improvements in treatment and supportive care approaches. This article presents recommendations of the European Myeloma Network for newly diagnosed patients based on the GRADE system for level of evidence. All patients with symptomatic disease should undergo risk stratification to classify patients for International Staging System stage (level of evidence: 1A) and for cytogenetically defined high- versus standard-risk groups (2B). Novel-agent-based induction and up-front autologous stem cell transplantation in medically fit patients remains the standard of care (1A). Induction therapy should include a triple combination of bortezomib, with either adriamycin or thalidomide and dexamethasone (1A), or with cyclophosphamide and dexamethasone (2B). Currently, allogeneic stem cell transplantation may be considered for young patients with high-risk disease and preferably in the context of a clinical trial (2B). Thalidomide (1B) or lenalidomide (1A) maintenance increases progression-free survival and possibly overall survival (2B). Bortezomib-based regimens are a valuable consolidation option, especially for patients who failed excellent response after autologous stem cell transplantation (2A). Bortezomib-melphalan-prednisone or melphalan-prednisone-thalidomide are the standards of care for transplant-ineligible patients (1A). Melphalan-prednisone-lenalidomide with lenalidomide maintenance increases progression-free survival, but overall survival data are needed. New data from the phase III study (MM-020/IFM 07-01) of lenalidomide-low-dose dexamethasone reached its primary end point of a statistically significant improvement in progression-free survival as compared to melphalan-prednisone-thalidomide and provides further evidence for the efficacy of lenalidomide-low-dose dexamethasone in transplant-ineligible patients (2B).

Diagnosis and risk stratification in multiple myeloma

Multiple myeloma (MM) is a tumor of monoclonal plasma cells, which produce a monoclonal antibody and expand predominantly in the bone marrow. Patients present with hypercalcemia, renal impairment, anemia, and/or bone disease. Only patients with symptomatic MM require therapy, whereas asymptomatic patients receive regular follow-up. Survival of patients with MM is very heterogeneous. The variety in outcome is explained by host factors as well as tumor-related characteristics reflecting biology of the MM clone and tumor burden. The identification of cytogenetic abnormalities by fluorescence in situ hybridization is currently the most important and widely available prognostic factor in MM.

Treatment with bortezomib-based regimens improves overall response and predicts for survival in patients with primary or secondary plasma cell leukemia: Analysis of the Greek myeloma study group

Plasma cell leukemia (PCL) is a rare and aggressive plasma cell disorder, with poor outcome. Bortezomib-based regimens (BBR) are highly effective in myeloma, but there is limited information about their efficacy and safety in PCL. Thus, we retrospectively collected data from 42 consecutive PCL patients (25 with primary PCL-pPCL and 17 with secondary PCL-sPCL) to explore the role of BBR in this entity. BBR were administered in 29 of 42 patients, while 6 of 25 patients with pPCL underwent autologous transplantation. Objective response (≥partial response) was significantly higher in patients treated with BBR versus conventional therapies (69% vs. 30.8%, P = 0.04); 27.5% of patients treated with BBR achieved at least very good partial response (vgPR). The highest ORR was observed in pPCL patients treated with BBR (88.9%; ≥vgPR: 33.3%). In BBR-group, grade 3 of 4 hematological, neurological and renal toxicity and neutropenic infections were observed in 41.4%, 7%, 3.4%, and 31%, respectively. With a median follow-up of 51 months, median overall survival (OS) for patients treated with BBR versus conventional therapies was 13 versus 2 months (P < 0.007). Median OS of patients with pPCL and sPCL treated with BBR was 18 and 7 months, respectively (P < 0.001). In the multivariate analysis normal PLTs, treatment with BBR and high quality response were the only powerful predictors for survival. Our study carrying the longest reported median follow-up, demonstrated that treatment of PCL with BBR induces high response rates and prolongs survival over conventional therapies, regardless of additional autologous transplantation rescue or established high risk features, with manageable toxicity.

Successful bortezomib/dexamethasone induction therapy with lenalidomide in an elderly patient with primary plasma cell leukemia complicated by renal failure and pulmonary hypertension

Primary plasma cell leukemia (PPCL) is a rare disease that progresses rapidly. In such cases, it is difficult to achieve remission, and early intensive chemotherapy is recommended. We herein describe the case of a 76-year-old man with PPCL complicated by renal failure and pulmonary hypertension. Bortezomib/dexamethasone induction therapy with lenalidomide was administered in association with continuous hemodiafiltration (CHDF). Complete remission was achieved after a single course of treatment, resulting in the cessation of CHDF. With the patient in remission, the administration of beraprost and bosentan resulted in improvements in the pulmonary hypertension. The results of this case report support the use of bortezomib/lenalidomide/dexamethasone combination therapy as an effective treatment for elderly PPCL patients with various complications.

Individualized therapy in multiple myeloma: are we there?

Multiple myeloma (MM), a heterogeneous plasma cell dyscrasia with a variety of clinical presentations and outcomes, is undergoing a treatment renaissance. While new drug classes have been discovered, a subset of high-risk MM remains relatively refractory to treatment. Current risk stratifications models, such as Durie-Salmon and the International Staging System, estimate disease burden and prognosis. Cytogenetics and gene expression profiles can help further identify more aggressive disease. Additionally, molecular and immunophenotypic assessment of minimal residual disease (MRD) and different imaging studies can identify patients at higher risk for relapse. It is now an opportune time to develop algorithms to combine all of the currently available clinical and genomic information to begin to inform specific therapeutic intervention in individual patients or at least smaller subgroups with similarly behaving disease.

Transient Plasmacytosis With Trisomy of Chromosome 8 in a Patient With Multiple Myeloma: A Case Report

A 96-year-old woman with a 5-year history of multiple myeloma was admitted to our hospital because of increasing fatigue and fever. Bone marrow plasma cell analysis showed t(11;14), del(13q), and del(17p13). Her condition deteriorated, and she developed plasmacytosis resembling plasma cell leukemia. Chromosome analysis showed trisomy of chromosome 8 in the circulating plasma cells. The plasmacytosis resolved spontaneously without chemotherapy after about 5 weeks, and the trisomy became undetectable. The findings suggest that trisomy 8 might have contributed to the transient plasmacytosis, and that chromosome 8 carries genes associated with plasma cell proliferation, maturation, and apoptosis.

New developments in the management and treatment of newly diagnosed and relapsed/refractory multiple myeloma patients

INTRODUCTION

The introduction of autologous stem cell transplantation as well as novel agents such as proteasome inhibitors (bortezomib) and immunomodulatory drugs (IMiDs; thalidomide and lenalidomide) have significantly improved long-term outcome of multiple myeloma patients. However, patients with high-risk disease at diagnosis had less benefit from these new strategies. In addition, myeloma patients with lenalidomide and bortezomib double-refractory disease have a very poor survival.

AREAS COVERED

Several next generation novel agents are active in patients with double-refractory disease including carfilzomib and pomalidomide. Various monoclonal antibodies are also promising in the setting of relapsed/refractory disease, including daratumumab, elotuzumab and lorvotuzumab mertansine. This editorial will focus on the most promising next generation novel agents for the treatment of multiple myeloma.

EXPERT OPINION

Incorporation of these new novel agents in frontline therapies will lead to more effective and less toxic combination therapies. Furthermore, new diagnostic techniques such as gene-expression profiling and next-generation sequencing will hopefully result in more personalized treatments for molecularly-defined subgroups.

Immune checkpoint blockade immunotherapy to activate anti-tumour T-cell immunity

The tumour microenvironment plays a dual role in cancer: it can promote tumour progression by establishing pro-tumour survival conditions but can also suppress tumour progression by killing cancer cells or inhibiting their outgrowth. These dynamically interconnected processes are under intense investigation to better understand cancer pathophysiology and allow identification of new therapeutic approaches. The ability of cancer cells to evade anti-tumour T-cell activity in the microenvironment has recently been accepted as a hallmark of cancer progression. This review will highlight the most promising therapeutic approach aimed at activating anti-tumour T-cell immunity in the cancer microenvironment: blocking inhibitory immune regulatory proteins (immune checkpoint ligands and receptors). There is emerging evidence that haematological tumours co-opt immune checkpoints as a major immune resistance mechanism. Pre-clinical findings indicate that targeted therapies and blockade of immune checkpoints could be combined to promote therapeutic synergy and long-term anti-tumour immunity to improve clinical outcomes for cancer patients.

Biological and clinical relevance of miRNA expression signatures in primary plasma cell leukemia

PURPOSE

Primary plasma cell leukemia (pPCL) is a rare and very aggressive form of plasma cell dyscrasia. To date, no information on microRNA (miRNA) expression in pPCL has been reported. This study aimed at investigating the involvement of miRNAs in pPCL and their possible relationship with higher tumor aggressiveness.

EXPERIMENTAL DESIGN

Global miRNA expression profiles were analyzed in highly purified malignant plasma cells from 18 pPCL untreated patients included in a prospective clinical trial. MiRNA expression patterns were evaluated in comparison with a representative series of multiple myeloma patients, in relation to the most recurrent chromosomal abnormalities (as assessed by fluorescence in situ hybridization and single-nucleotide polymorphism-array analysis), and in association with clinical outcome. MiRNA expression was also integrated with gene expression profiles in pPCL and multiple myeloma samples.

RESULTS

We identified a series of deregulated miRNAs in pPCL (42 upregulated and 41 downregulated) in comparison with multiple myeloma. Some of them, on the basis of their reported functions and putative target genes computed by integrative analysis, might have a role in the pathobiology of pPCL. As regards chromosomal aberrations, the expression of some miRNAs mapped to hotspot altered regions was associated with DNA copy number of the corresponding loci. Finally, 4 miRNA (miR-497, miR-106b, miR-181a*, and miR-181b) were identified as having expression levels that correlated with treatment response, and 4 (miR-92a, miR-330-3p, miR-22, and miR-146a) with clinical outcome.

CONCLUSIONS

Overall, our study provides insights into the possible contribution of miRNAs in the pathogenesis of pPCL and suggests targets for future therapeutic investigations.

High-output cardiac failure revealing primary plasma cell leukemia

High-output cardiac failure in multiple myeloma (MM) is related to arteriovenous shunting in bone infiltrate disease. We describe such a complication in a patient with primary plasma cell leukemia (pPCL) without bone disease. We review the mechanisms that could be involved. As previously described, traditional cardiac failure therapy is not effective. pPCL therapy should not be delayed.

Plasma cell leukemia: consensus statement on diagnostic requirements, response criteria and treatment recommendations by the International Myeloma Working Group

Plasma cell leukemia (PCL) is a rare and aggressive variant of myeloma characterized by the presence of circulating plasma cells. It is classified as either primary PCL occurring at diagnosis or as secondary PCL in patients with relapsed/refractory myeloma. Primary PCL is a distinct clinic-pathological entity with different cytogenetic and molecular findings. The clinical course is aggressive with short remissions and survival duration. The diagnosis is based upon the percentage (≥ 20%) and absolute number (≥ 2 × 10(9)/l) of plasma cells in the peripheral blood. It is proposed that the thresholds for diagnosis be re-examined and consensus recommendations are made for diagnosis, as well as, response and progression criteria. Induction therapy needs to begin promptly and have high clinical activity leading to rapid disease control in an effort to minimize the risk of early death. Intensive chemotherapy regimens and bortezomib-based regimens are recommended followed by high-dose therapy with autologous stem cell transplantation if feasible. Allogeneic transplantation can be considered in younger patients. Prospective multicenter studies are required to provide revised definitions and better understanding of the pathogenesis of PCL.