Genetic aberrations and survival in plasma cell leukemia

Spatial genomic heterogeneity in multiple myeloma revealed by multi-region sequencing

In multiple myeloma malignant plasma cells expand within the bone marrow. Since this site is well-perfused, a rapid dissemination of "fitter" clones may be anticipated. However, an imbalanced distribution of multiple myeloma is frequently observed in medical imaging. Here, we perform multi-region sequencing, including iliac crest and radiology-guided focal lesion specimens from 51 patients to gain insight into the spatial clonal architecture. We demonstrate spatial genomic heterogeneity in more than 75% of patients, including inactivation of CDKN2C and TP53, and mutations affecting mitogen-activated protein kinase genes. We show that the extent of spatial heterogeneity is positively associated with the size of biopsied focal lesions consistent with regional outgrowth of advanced clones. The results support a model for multiple myeloma progression with clonal sweeps in the early phase and regional evolution in advanced disease. We suggest that multi-region investigations are critical to understanding intra-patient heterogeneity and the evolutionary processes in multiple myeloma.In multiple myeloma, malignant cells expand within bone marrow. Here, the authors use multi-region sequencing in patient samples to analyse spatial clonal architecture and heterogeneity, providing novel insight into multiple myeloma progression and evolution.

The novel autophagy inhibitor elaiophylin exerts antitumor activity against multiple myeloma with mutant TP53 in part through endoplasmic reticulum stress-induced apoptosis

Elaiophylin is a natural compound and a novel and potent inhibitor of late stage autophagy with outstanding antitumor activity in human ovarian cancer cells. However, the possible biologic effects and functional linkage between elaiophylin and multiple myeloma (MM) have not been explored. This study aimed to assess the effect of elaiophylin on MM cells with mutant TP53 and the possible molecular mechanism. The results suggested that elaiophylin exerted anti-myeloma activity by inducing apoptosis and proliferation arrest. As expected, elaiophylin blocked autophagy flux in MM cells. Subsequently, persistent activation of endoplasmic reticulum (ER) stress was induced. Moreover, the apoptotic effect was to some extent attenuated by the ER stress inhibitor tauroursodeoxycholic acid (TUDCA). Further studies indicated that elaiophylin effectively suppressed MM cell growth without obvious side effects in zebrafish embryo and mouse xenograft models. Taken together, our data are the first to demonstrate that exposure of human MM cells with mutant TP53 to elaiophylin blocked autophagy flux and thus induced cell death, which partially involved ER stress-associated apoptosis. Targeted disruption of the cellular protein handling system by elaiophylin is therefore a promising therapeutic strategy for overcoming incurable MM, even when TP53 mutations are present.

Incidence, characteristics, and outcome of solitary plasmacytoma and plasma cell leukemia. Population-based data from the Swedish Myeloma Register

Solitary plasmacytoma (SP) and plasma cell leukemia (PCL) are uncommon (3-6%) types of plasma cell disease. The risk of progression to symptomatic multiple myeloma (MM) is probably important for the outcome of SP. PCL is rare and has a dismal outcome. In this study, we report on incidence and survival in PCL/SP, and progression to MM in SP, using the prospective observational Swedish Multiple Myeloma Register designed to document all newly diagnosed plasma cell diseases in Sweden since 2008. Both solitary bone plasmacytoma (SBP) (n=124) and extramedullary plasmacytoma (EMP) (n=67) have better overall survival (OS) than MM (n=3549). Progression to MM was higher in SBP than in EMP (35% and 7% at 2 years, respectively), but this did not translate into better survival in EMP. In spite of treatment developments, the OS of primary PCL is still dismal (median of 11 months, 0% at 5 years). Hence, there is a great need for diagnostic and treatment guidelines as well as prospective studies addressing the role for alternative treatment options, such as allogeneic stem cell transplantation and monoclonal antibodies in the treatment of PCL.

The role of frontline autologous stem cell transplantation for primary plasma cell leukemia: a retrospective multicenter study (KMM160)

Primary plasma cell leukemia (pPCL) is a rare and aggressive plasma cell neoplasm, with rapidly progressing clinical course. We evaluated the treatment status and survival outcomes of 69 Korean patients with pPCL. Of them, 59 patients were treated; 15 (25.4%) were treated initially with novel agent-based regimens with upfront autologous stem cell transplantation (ASCT), 7 (11.9%) with conventional chemotherapy with upfront ASCT, 21 (35.6%) with novel agent-based regimens only, and 16 (27.1%) were treated with conventional chemotherapy alone. Overall response rates after initial therapy were significantly higher in patients treated with novel agent-based regimens compared with those treated with conventional chemotherapies (75% vs. 43.4%, P = 0.026). Median progression-free survival (PFS) and overall survival (OS) were 12.2 months and 16.1 months, respectively. The median PFS of the four treatment groups–conventional chemotherapy alone, novel agents alone, conventional chemotherapy with ASCT, and novel agents with ASCT–were 1.2, 9.0, 10.5, and 26.4 months, respectively (P < 0.001); the median OS of the four treatment groups were 2.9, 12.3, 14.1, and 31.1 months, respectively (P < 0.001). The median OS was also significantly better in the patients with novel agents with ASCT versus other patients. In a multivariate analysis, an increased lactate dehydrogenase level, low albumin (< 3.5 g/dL), and non-CR after front-line treatment were independently associated with poor PFS and OS. In conclusion, the use of novel agent-based therapy with ASCT and achieving a deep response to front-line treatment are important in expecting improved PFS and OS in patients with pPCL.

Therapy for Relapsed Multiple Myeloma: Guidelines From the Mayo Stratification for Myeloma and Risk-Adapted Therapy

Life expectancy in patients with multiple myeloma is increasing because of the availability of an increasing number of novel agents with various mechanisms of action against the disease. However, the disease remains incurable in most patients because of the emergence of resistant clones, leading to repeated relapses of the disease. In 2015, 5 novel agents were approved for therapy for relapsed multiple myeloma. This surfeit of novel agents renders management of relapsed multiple myeloma more complex because of the occurrence of multiple relapses, the risk of cumulative and emergent toxicity from previous therapies, as well as evolution of the disease during therapy. A group of physicians at Mayo Clinic with expertise in the care of patients with multiple myeloma regularly evaluates the evolving literature on the biology and therapy for multiple myeloma and issues guidelines on the optimal care of patients with this disease. In this article, the latest recommendations on the diagnostic evaluation of relapsed multiple myeloma and decision trees on how to treat patients at various stages of their relapse (off study) are provided together with the evidence to support them.

The Role of PI3K Isoforms in Regulating Bone Marrow Microenvironment Signaling Focusing on Acute Myeloid Leukemia and Multiple Myeloma

Despite the development of novel treatments in the past 15 years, many blood cancers still remain ultimately fatal and difficult to treat, particularly acute myeloid leukaemia (AML) and multiple myeloma (MM). While significant progress has been made characterising small-scale genetic mutations and larger-scale chromosomal translocations that contribute to the development of various blood cancers, less is understood about the complex microenvironment of the bone marrow (BM), which is known to be a key player in the pathogenesis of chronic lymphocytic leukaemia (CLL), AML and MM. This niche acts as a sanctuary for the cancerous cells, protecting them from chemotherapeutics and encouraging clonal cell survival. It does this by upregulating a plethora of signalling cascades within the malignant cell, with the phosphatidylinositol-3-kinase (PI3K) pathway taking a critical role. This review will focus on how the PI3K pathway influences disease progression and the individualised role of the PI3K subunits. We will also summarise the current clinical trials for PI3K inhibitors and how these trials impact the treatment of blood cancers.

Proteome alterations associated with transformation of multiple myeloma to secondary plasma cell leukemia

Plasma cell leukemia is a rare and aggressive plasma cell neoplasm that may either originate de novo (primary PCL) or by leukemic transformation of multiple myeloma (MM) to secondary PCL (sPCL). The prognosis of sPCL is very poor, and currently no standard treatment is available due to lack of prospective clinical studies. In an attempt to elucidate factors contributing to transformation, we have performed super-SILAC quantitative proteome profiling of malignant plasma cells collected from the same patient at both the MM and sPCL stages of the disease. 795 proteins were found to be differentially expressed in the MM and sPCL samples. Gene ontology analysis indicated a metabolic shift towards aerobic glycolysis in sPCL as well as marked down-regulation of enzymes involved in glycan synthesis, potentially mediating altered glycosylation of surface receptors. There was no significant change in overall genomic 5-methylcytosine or 5-hydroxymethylcytosine at the two stages, indicating that epigenetic dysregulation was not a major driver of transformation to sPCL. The present study constitutes the first attempt to provide a comprehensive map of the altered protein expression profile accompanying transformation of MM to sPCL in a single patient, identifying several candidate proteins that can be targeted by currently available small molecule drugs. Our dataset furthermore constitutes a reference dataset for further proteomic analysis of sPCL transformation.

p53 dysregulation in B-cell malignancies: More than a single gene in the pathway to hell

TP53 deletion or mutation is frequent in B-cell malignancies and is associated with a low response rate. We describe here the p53 landscape in B-cell malignancies, from B-Acute Lymphoblastic Leukemia to Plasma Cell Leukemia, by analyzing incidence of gain or loss of function of actors both upstream and within the p53 pathway, namely MYC, RAS, ARF, MDM2, ATM and TP53. Abnormalities are not equally distributed and their incidence is highly variable among malignancies. Deletion and mutation, usually associated, of ATM or TP53 are frequent in Diffuse Large B-Cell Lymphoma and Mantle Cell Lymphoma. MYC gain, absent in post-GC malignancies, is frequent in B-Prolymphocytic-Leukemia, Multiple Myeloma and Plasma Cell Leukemias. RAS mutations are rare except in MM and PCL. Multiple Factorial Analysis notes that MYC deregulation is closely related to TP53 status. Moreover, MYC gain, TP53 deletion and RAS mutations are inversely correlated with survival. Based on this landscape, we further propose targeted therapeutic approaches for the different B-cell malignancies.

Prognostic impact of circulating plasma cells in patients with multiple myeloma: implications for plasma cell leukemia definition

The presence of circulating plasma cells in patients with multiple myeloma is considered a marker for highly proliferative disease. In the study herein, the impact of circulating plasma cells assessed by cytology on survival of patients with multiple myeloma was analyzed. Wright-Giemsa stained peripheral blood smears of 482 patients with newly diagnosed myeloma or plasma cell leukemia were reviewed and patients were classified into 4 categories according to the percentage of circulating plasma cells: 0%, 1–4%, 5–20%, and plasma cell leukemia with the following frequencies: 382 (79.2%), 83 (17.2%), 12 (2.5%) and 5 (1.0%), respectively. Median overall survival according to the circulating plasma cells group was 47, 50, 6 and 14 months, respectively. At multivariate analysis, the presence of 5 to 20% circulating plasma cells was associated with a worse overall survival (relative risk 4.9, 95% CI 2.6–9.3) independently of age, creatinine, the Durie-Salmon system stage and the International Staging System (ISS) stage. Patients with ≥5% circulating plasma cells had lower platelet counts (median 86×10⁹/L vs. 214×10⁹/L, P<0.0001) and higher bone marrow plasma cells (median 53% vs. 36%, P=0.004). The presence of ≥5% circulating plasma cells in patients with multiple myeloma has a similar adverse prognostic impact as plasma cell leukemia.

Successful Intrathecal Chemotherapy Combined with Radiotherapy Followed by Pomalidomide and Low-Dose Dexamethasone Maintenance Therapy for a Primary Plasma Cell Leukemia Patient

Primary plasma cell leukemia (PPCL) is a rare aggressive variant of plasma cell disorder and frequently presents with extramedullary disease. Central nervous system (CNS) involvement with PPCL has an extremely poor prognosis. We describe a 46-year-old man with PPCL treated with a combination of lenalidomide, bortezomib, and dexamethasone as induction therapy following upfront allogeneic stem cell transplantation (allo-SCT). Despite achieving a very good partial response, the patient suffered from an isolated CNS relapse 12 months after allo-SCT. He was immediately started on concurrent intrathecal chemotherapy (IT) and cranial irradiation (RT). Subsequently, pomalidomide and low-dose dexamethasone (Pd) were given as maintenance therapy. He has been without CNS recurrence for more than 18 months. Our case suggests that concurrent IT and RT followed by Pd maintenance therapy may be an effective option to control CNS relapse of PPCL after allo-SCT.

Radiographic features of plasma cell leukemia in the maxilla: A case report

Plasma cell leukemia (PCL) is an aggressive form of multiple myeloma where there is hematogenous spread of abnormal plasma cells into the periphery. This is opposed to multiple myeloma, where the abnormal plasma cells stay in the bone marrow. PCL is more common in males than females, and is also more common in African-Americans than Caucasians. Signs and symptoms of PCL include, but are not limited to, renal insufficiency, hypercalcemia, anemia, lytic bone lesions, thrombocytopenia, hepatomegaly, and splenomegaly. Here, we discussed a case of a 71-year-old Caucasian female recently diagnosed with primary PCL with radiographic features of this disease throughout the body, with an emphasis on the maxillofacial skeleton and relevance from a dental standpoint.

Concomitant MDS with isolated 5q deletion and MGUS: case report and review of molecular aspects

Patients with monoclonal gammopathy of undetermined significance (MGUS) have a higher risk for the development of concomitant primary cancers such as multiple myeloma (MM) and myelodysplastic syndrome (MDS). We report the case of patient initially suffering from MGUS of the IgG lambda subtype for more than 10 yr, which evolved to MM and MDS with deletion (5q) with severe pancytopenia. Due to pancytopenia, he received dose-reduced treatment with lenalidomide and dexamethasone. He achieved an ongoing transfusion independency after about 1 month of treatment. Bone marrow taken 14 months after start of treatment showed a complete cytogenetic response of the del(5q) clone and a plasma cell infiltration below 5%. In contrast to the development of MM in MGUS patients, the subsequent occurrence of MDS after diagnosis of MGUS is infrequent. Moreover, the biological association of MDS with MGUS is not sufficiently understood, but the non-treatment-related occurrence supports the pathogenetic role of pre-existing alterations of stem cells. Here, we summarize data on concomitant MDS and MGUS/MM with particular emphasis on molecular aspects.

[Primary plasma cell leukemia: about 3 cases]

La leucémie à plasmocytes est une hémopathie maligne rare définie par la présence de plus de 20 % de plasmocytes de la formule leucocytaire ou un nombre de plasmocytes circulants supérieur à 2 × 10⁹/L (2G/L). Elle peut être primitive, dans 60% des cas, et se manifeste d'emblée sur un mode leucémique ou secondaire, dans 40% des cas, compliquant un myélome multiple connu. Vu la rareté de cette affection, seuls quelques cas ont été rapportés dans la littérature. Elle est caractérisée par son agressivité et son mauvais pronostic. A travers 03 cas diagnostiqués au laboratoire d'hématologie de l'hôpital militaire Mohammed V les auteurs présentent les particularités cliniques, biologiques et pronostic de cette affection.

Outcomes in patients with multiple myeloma with TP53 deletion after autologous hematopoietic stem cell transplant

TP53 gene deletion is associated with poor outcomes in multiple myeloma (MM). We report the outcomes of patients with MM with and without TP53 deletion who underwent immunomodulatory drug (IMiD) and/or proteasome inhibitor (PI) induction followed by autologous hematopoietic stem cell transplant (auto-HCT). We identified 34 patients with MM and TP53 deletion who underwent IMiD and/or PI induction followed by auto-HCT at our institution during 2008-2014. We compared their outcomes with those of control patients (n = 111) with MM without TP53 deletion. Median age at auto-HCT was 59 years in the TP53-deletion group and 58 years in the control group (P = 0.4). Twenty-one patients (62%) with TP53 deletion and 69 controls (62%) achieved at least partial remission before auto-HCT (P = 0.97). Twenty-three patients (68%) with TP53 deletion and 47 controls (42%) had relapsed disease at auto-HCT (P = 0.01). Median progression-free survival was 8 months for patients with TP53 deletion and 28 months for controls (P < 0.001). Median overall survival was 21 months for patients with TP53 deletion and 56 months for controls (P < 0.001). On multivariate analysis of both groups, TP53 deletion (hazard ratio 3.4, 95% confidence interval 1.9-5.8, P < 0.001) and relapsed disease at auto-HCT (hazard ratio 2.0, 95% confidence interval 1.2-3.4, P = 0.008) were associated with a higher risk of earlier progression. In MM patients treated with PI and/or IMiD drugs, and auto-HCT, TP53 deletion and relapsed disease at the time of auto-HCT are independent predictors of progression. Novel approaches should be evaluated in this high-risk population. Am. J. Hematol. 91:E442-E447, 2016. © 2016 Wiley Periodicals, Inc.

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.

VOLIN and KJON-Two novel hyperdiploid myeloma cell lines

Multiple myeloma can be divided into two distinct genetic subgroups: hyperdiploid (HRD) or nonhyperdiploid (NHRD) myeloma. Myeloma cell lines are important tools to study myeloma cell biology and are commonly used for preclinical screening and testing of new drugs. With few exceptions human myeloma cell lines are derived from NHRD patients, even though about half of the patients have HRD myeloma. Thus, there is a need for cell lines of HRD origin to enable more representative preclinical studies. Here, we present two novel myeloma cell lines, VOLIN and KJON. Both of them were derived from patients with HRD disease and shared the same genotype as their corresponding primary tumors. The cell lines' chromosomal content, genetic aberrations, gene expression, immunophenotype as well as some of their growth characteristics are described. Neither of the cell lines was found to harbor immunoglobulin heavy chain translocations. The VOLIN cell line was established from a bone marrow aspirate and KJON from peripheral blood. We propose that these unique cell lines may be used as tools to increase our understanding of myeloma cell biology. © 2016 Wiley Periodicals, Inc.

Whole-exome sequencing of primary plasma cell leukemia discloses heterogeneous mutational patterns

Primary plasma cell leukemia (pPCL) is a rare and aggressive form of plasma cell dyscrasia and may represent a valid model for high-risk multiple myeloma (MM). To provide novel information concerning the mutational profile of this disease, we performed the whole-exome sequencing of a prospective series of 12 pPCL cases included in a Phase II multicenter clinical trial and previously characterized at clinical and molecular levels. We identified 1, 928 coding somatic non-silent variants on 1, 643 genes, with a mean of 166 variants per sample, and only few variants and genes recurrent in two or more samples. An excess of C > T transitions and the presence of two main mutational signatures (related to APOBEC over-activity and aging) occurring in different translocation groups were observed. We identified 14 candidate cancer driver genes, mainly involved in cell-matrix adhesion, cell cycle, genome stability, RNA metabolism and protein folding. Furthermore, integration of mutation data with copy number alteration profiles evidenced biallelically disrupted genes with potential tumor suppressor functions. Globally, cadherin/Wnt signaling, extracellular matrix and cell cycle checkpoint resulted the most affected functional pathways. Sequencing results were finally combined with gene expression data to better elucidate the biological relevance of mutated genes. This study represents the first whole-exome sequencing screen of pPCL and evidenced a remarkable genetic heterogeneity of mutational patterns. This may provide a contribution to the comprehension of the pathogenetic mechanisms associated with this aggressive form of PC dyscrasia and potentially with high-risk MM.

Plasma cell leukaemia

Plasma cell leukaemia (PCL) is a rare and aggressive disease. Diagnosis is made when there are >2000/#mL circulating plasma cells in peripheral blood or plasmacytosis >20% of total leukocyte count. We report a case of a 51-year old man with generalized bone pain and constitutional symptoms. Blood peripheral smear revealed leukocytosis with 39% plasma cells. Bone marrow biopsy showed plasma cell invasion, which confirmed the diagnosis of PCL. Additionally, the patient had markers of advanced disease. Chemotherapy with vincristine, adriamycin and dexamethasone was started. Despite an initial favourable response, the patient died 2 months later due to an infectious complication. PCL has no established treatment and has a dismal prognosis, requiring the achievement of better data to improve the disease course.

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.

Genetic aberrations in multiple myeloma characterized by cIg-FISH: a Brazilian context

Genetic abnormalities are critical prognostic factors for patients diagnosed with multiple myeloma (MM). This retrospective, multicenter study aimed to contribute with the genetic and clinical characterization of MM patients in a country with continental dimensions such as Brazil. Genetic abnormalities were assessed by cIg-fluorescent in situ hybridization (cIg-FISH) in a series of 152 MM patients (median age 55 years, 58.5% men). Overall, genetic abnormalities were detected in 52.7% (80/152) of patients. A 14q32 rearrangement was detected in 33.5% (n=51), including t(11;14), t(4;14) and t(14;16) in 18.4, 14.1, and 1% of cases, respectively. del(13q) was identified in 42.7% (n=65) of patients, of whom 49.2% (32/65) presented a concomitant 14q32 rearrangement. del(17p) had a frequency of 5.2% (n=8). del(13q) was associated with high plasma cell burden (≥50%, P=0.02), and del(17p) with advanced ISS stages (P=0.05) and extramedullary disease (P=0.03). t(4;14) was associated with advanced Durie-Salmon stages (P=0.008), renal insufficiency (P=0.01) and was more common in patients over 60 years old. This study reports similar frequencies of genetic abnormalities to most series worldwide, whereas the t(14;16) and del(17p), two high risk factors for newly diagnosed patients, exhibited lower frequencies. Our results expand the knowledge on the molecular features of MM in Brazil, a country where innovative therapies that could overcome a poor prognosis for some genetic abnormalities are not always available.

Laboratory testing requirements for diagnosis and follow-up of multiple myeloma and related plasma cell dyscrasias

Monoclonal immunoglobulins are markers of plasma cell proliferative diseases and have been described as the first (and perhaps best) serological tumor marker. The unique structure of each monoclonal protein makes them highly specific for each plasma cell clone. The difficulties of using monoclonal proteins for diagnosing and monitoring multiple myeloma, however, stem from the diverse disease presentations and broad range of serum protein concentrations and molecular weights. Because of these challenges, no single test can confidently diagnose or monitor all patients. Panels of tests have been recommended for sensitivity and efficiency. In this review we discuss the various disease presentations and the use of various tests such as protein electrophoresis and immunofixation electrophoresis as well as immunoglobulin quantitation, free light chain quantitation, and heavy-light chain quantitation by immuno-nephelometry. The choice of tests for inclusion in diagnostic and monitoring panels may need to be tailored to each patient, and examples are provided. The panel currently recommended for diagnostic screening is serum protein electrophoresis, immunofixation electrophoresis, and free light chain quantitation.

Genomic Aberrations in Multiple Myeloma

Multiple myeloma (MM) is a genetically complex disease. The past few years have seen an evolution in cancer research with the emergence of next-generation sequencing (NGS), enabling high throughput sequencing of tumors-including whole exome, whole genome, RNA, and single-cell sequencing as well as genome-wide association study (GWAS). A few inherited variants have been described, counting for some cases of familial disease. Hierarchically, primary events in MM can be divided into hyperdiploid (HDR) and nonhyperdiploid subtypes. HRD tumors are characterized by trisomy of chromosomes 3, 5, 7, 9, 11, 15, 19, and/or 21. Non-HRD tumors harbor IGH translocations, mainly t(4;14), t(6;14), t(11;14), t(14;16), and t(14;20). Secondary events participate to the tumor progression and consist in secondary translocation involving MYC, copy number variations (CNV) and somatic mutations (such as mutations in KRAS, NRAS, BRAF, P53). Moreover, the dissection of clonal heterogeneity helps to understand the evolution of the disease. The following review provides a comprehensive review of the genomic landscape in MM.

Risk of Early Mortality in Patients With Newly Diagnosed Multiple Myeloma

The overall survival of patients with multiple myeloma (MM) has been improved greatly over the last 2 decades with the broader use of novel drugs and autologous tandem transplantation. However, more than one tenth of myeloma patients still die shortly after diagnosis. We therefore aim to investigate the risk factors of early mortality (death within 60 days after diagnosis) in patients with MM. We included in this study 451 consecutive patients with MM, newly diagnosed at an Asian tertiary medical center between January 1, 2002 and April 30, 2015. A total of 57 subjects who experienced early mortality were identified. Risk factors for early mortality in myeloma patients were collected and analyzed. Early mortality occurred in 57 (12.6%) of the myeloma patients. In the multivariate analysis, being male (adjusted OR 2.93, 95% CI 1.17-7.31), serum albumin < 3.5  g/dL (adjusted OR 2.71, 95% CI 1.09-6.74), primary plasma cell leukemia (adjusted OR 17.61, 95% CI 1.01-306.05), serum albumin (adjusted OR 2.70, 95% CI 1.15-6.38), corrected serum calcium ≥ 12  mg/dL (adjusted OR 2.94, 95% CI 1.21-7.14), and LDH ≥ 250  U/L (adjusted OR 3.07, 95% CI 1.50-6.27) were identified as independent risk factors of early mortality. Pneumonia with other infections contributed most to early mortality (n = 36, 65%), followed by renal failure and cardiac failure. The early mortality rate is high (12.6%) in patients with MM. Patients who are male and those with primary plasma cell leukemia, low serum albumin, high-corrected serum calcium, or LDH are at risk of early mortality. Nearly two thirds of the myeloma patients who experienced early mortality in our study (37 of 57, 65%) died of infection. Once a high-risk group is identified, much effort is required to target new approaches for prevention, early detection, and treatment of infections.

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.

The t(11;14)(q13;q32) translocation as a poor prognostic parameter for autologous stem cell transplantation in myeloma patients with extramedullary plasmacytoma

INTRODUCTION

Fluorescence in-situ hybridization (FISH)-detected abnormalities, including del(17p), del(13q), and t(4;14), have been associated with inferior prognosis. However, there are few data about the prognostic significance of cytogenetic abnormalities for autologous stem cell transplantation (ASCT) in multiple myeloma (MM) patients with extramedullary plasmacytoma (EMP).

PATIENTS AND METHODS

Between April 2004 and December 2012, 290 MM patients underwent ASCT at 3 centers. FISH data for bone marrow samples obtained at diagnosis were available for 58 patients who had EMP at diagnosis or during treatment.

RESULTS

The t(11;14), t(4;14), del(13q), and 1q gain abnormalities were seen in 14.9%, 6.3%, 25.6%, and 42.9%, respectively. No t(14;16) or del(17p) cytogenetic abnormality was detected in the examined patients. Patients with t(11;14) had a lower response rate compared to patients with other cytogenetic abnormalities. EMP-specific relapse was higher in patients with t(11;14) than in patients with other cytogenetic abnormalities (42.9% vs. 10%-33.3%). Each of the 4 cytogenetic abnormalities predicted shorter median progression-free survival (6-12 months vs. 27-37 months) and shorter overall survival (16-22 months vs. 68 months or not reached) compared to no cytogenetic abnormality. The t(11;14) translocation was an important prognostic factor for both progression-free survival (hazard ratio, 25.154; P < .001) and overall survival (hazard ratio, 7.484; P = .024) in the multivariate analysis.

CONCLUSION

In the current study, t(11;14), t(4;14), del(13q), and 1q gain were associated with worse survival in MM patients with EMP. The role of t(11;14) as a prognostic parameter for ASCT in MM patients with EMP should be confirmed with a large, well-designed study.

Staging and prognostication of multiple myeloma

Multiple myeloma (MM) is a heterogeneous disease that, over the past 15 years, has seen an increased understanding of its biology and of novel therapeutic options. Distinctive subtypes of the disease have been described, each with different outcomes and clinic-pathological features. Even though a detailed classification of MM into at least seven or eight major subtypes is possible, a more practical clinical approach can classify the disease into high-risk and non-high-risk MM. Such classification has permitted a more personalized approach to the management of the disease. Additionally, risk stratification should be included in outcome discussions with patients, as survival differs significantly by high-risk status. Nowadays, test for risk stratification are widely available and can be routinely used in the clinic. A greater understanding of the genetic abnormalities underlying the biology of MM will allow for the development of novel targeted therapies and better prognostic markers of the disease.

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.

Trends in survival of patients with primary plasma cell leukemia: a population-based analysis

Primary plasma cell leukemia (pPCL) is a rare malignancy with an aggressive course and poor outcome. There has been significant improvement in the survival of multiple myeloma patients over the past decade as a result of incorporating autologous stem cell transplantation (ASCT) and novel agents into treatment regimens. However, it is unknown whether these therapies have had a similar impact on the survival of patients with pPCL. We conducted an analysis of the Surveillance, Epidemiology, and End Results database to evaluate the trends in survival of 445 patients with pPCL between 1973 and 2009. The widespread availability of ASCT and use of novel agents in the upfront setting of multiple myeloma and pPCL began after 1995 and 2006, respectively. The median overall survival based on periods of diagnosis were 5, 6, 4, and 12 months for those diagnosed during 1973-1995, 1996-2000, 2001-2005, and 2006-2009, respectively (P = .001). Thus, the current study confirms the recent survival improvement in pPCL within a large US population that may be associated with the use of better therapeutic strategies.

MicroRNA: important player in the pathobiology of multiple myeloma

Recent studies have revealed a pivotal role played by a class of small, noncoding RNAs, microRNA (miRNA), in multiple myeloma (MM), a plasma cell (PC) malignancy causing significant morbidity and mortality. Deregulated miRNA expression in patient's PCs and plasma has been associated with tumor progression, molecular subtypes, clinical staging, prognosis, and drug response in MM. A number of important oncogenic and tumor suppressor miRNAs have been discovered to regulate important genes and pathways such as p53 and IL6-JAK-STAT signaling. miRNAs may also form complex regulatory circuitry with genetic and epigenetic machineries, the deregulation of which could lead to malignant transformation and progression. The translational potential of miRNAs in the clinic is being increasingly recognized that they could represent novel biomarkers and therapeutic targets. This review comprehensively summarizes current progress in delineating the roles of miRNAs in MM pathobiology and management.