Beyond the marrow: insights from comprehensive next-generation sequencing of extramedullary multiple myeloma tumors.

Extramedullary multiple myeloma (EMM) is an aggressive form of multiple myeloma (MM). This study represents the most comprehensive next-generation sequencing analysis of EMM tumors (N = 14) to date, uncovering key molecular features and describing the tumor microenvironment. We observed the co-occurrence of 1q21 gain/amplification and MAPK pathway mutations in 79% of EMM samples, suggesting that these are crucial mutational events in EMM development. We also demonstrated that patients with mutated KRAS and 1q21 gain/amplification at the time of diagnosis have a significantly higher risk of EMM development (HR = 2.4, p = 0.011) using data from a large CoMMpass dataset. We identified downregulation of CXCR4 and enhanced cell proliferation, along with reduced expression of therapeutic targets (CD38, SLAMF7, GPRC5D, FCRH5), potentially explaining diminished efficacy of immunotherapy. Conversely, we identified significantly upregulated EZH2 and CD70 as potential future therapeutic options. For the first time, we report on the tumor microenvironment of EMM, revealing CD8+ T cells and NK cells as predominant immune effector cells using single-cell sequencing. Finally, this is the first longitudinal study in EMM revealing the molecular changes from the time of diagnosis to EMM relapse.

Gamma-heavy chain disease.

BACKGROUND: Gamma-heavy chain disease is a rare disease, described so far in approximately 150 cases. The aim of this work was laboratory dia-gnostics of immunoglobulin heavy chain disease. MATERIALS AND METHODS: A 60-year-old patient was referred to the University Hospital in Ostrava for suspected marginal zone lymphoma from gastric bio-psy. Staging examinations including bone marrow trepanobio-psy and PET/CT were added; special examinations required serum protein electrophoresis, immunofixation electrophoresis, determination of polyclonal immunoglobulins, free light chains, and immunoglobulin heavy/light chain pairs. Isoelectric focusing in agarose gel followed by affinity immunoblotting and SDS electrophoresis was added due to unclear findings. RESULTS: 0.1 % of plasma cells were found in the bone marrow, of which 87 % were clonal (pathological) plasma cells, followed by the cyt cytotype LAMBDA + CD38 + CD138 + CD45 + CD19 + CD56- CD27 + CD81- CD117-. Monoclonal heavy chains were found in the patients serum. No monoclonal immunoglobulin heavy or light chains were detected in urine. The PET/CT examination showed generalized lymphadenopathy, splenomegaly and inhomogeneous accumulation of fluorodeoxyglucose in axillary and appendicular skeleton, but without the presence of typical osteolytic lesions. CONCLUSION: Monoclonal heavy chains of immunoglobulins are a rare disease. In contrast to the detection of a complete paraprotein molecule, additional methods must be used to confirm them. The finding of monoclonal heavy chain gamma in the serum of the study patient is related to the presence of marginal zone lymphoma, which was proven from a gastric bio-psy. The study was supported by the project of MH CZ - DRO - FNOs /2017 (Biobank in Teaching Hospital Ostrava) The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.

Bortezomib retreatment is effective in relapsed multiple myeloma patients - real-life clinical practice data.

Nowadays, bortezomib, a proteasome inhibitor, is widely used in treatment of newly diagnosed or relapsed multiple myeloma. The aim of this study was to analyze efficiency of bortezomib retreatment in patients with relapsed or refractory multiple myeloma. From 2004 to 2016, 283 patients were retrospectively evaluated at all hematological centers in the Czech Republic. Bortezomib was administered at the standard dosing and in combined therapy with corticosteroids, chemotherapy or thalidomide. Before bortezomib retreatment, 61% of patients received previous lenalidomide treatment, 40.6% autologous transplantation, and median number of prior lines of therapy was three. In total, 21% of patients were refractory to the first bortezomib treatment. In bortezomib retreatment, overall response rate was 34.5%, median progression-free survival was 7.8 months (95% CI: 6.7-8.9), median duration of response was 10.5 months (95% CI: 8.0-13.0) and median overall survival was 20.3 months (95% CI: 17.9-22.7). Grade 3-4 adverse events included thrombocytopenia, neutropenia, anemia and infection. Neuropathy grade 2 or higher occurred in 19.4% of patients. We conclude that bortezomib retreatment is an effective and safe therapeutic alternative for relapsed or refractory multiple myeloma patients.

Lenalidomide and dexamethasone in treatment of patients with relapsed and refractory multiple myeloma - analysis of data from the Czech Myeloma Group Registry of Monoclonal Gammopathies.

Lenalidomide (LEN) is an immunomodulator with clinical activity against myeloma cells. Based on the pivotal phase 3 trials MM-009 and MM010, the combination of lenalidomide and dexamethasone(DEX) was approved for patients with multiple myeloma who received at least one prior therapy. Here, we evaluated LEN/DEX therapy in unselected population and subsequently in selected sub-groups of patients with relapsed/refractory multiple myeloma followed in the Registry of Monoclonal Gammopathies of the Czech Myeloma Group. Altogether 858 patients were treated with LEN/DEX in the Czech Republic and Slovakia until end of 2017. The analyzed sub-groups were defined as patients with high risk cytogenetic aberrations and patients with relapsed and refractory MM. The overall response rate (ORR; partial remission or better response, PR) in the whole group of patients was 46.3% for all lines of therapy, 26.4% for high-risk group and 32.1% for relapsed and refractory group. Medians of overall survival (OS) in the same cohorts were as follows: 25.6, 15.7 and 18.5 months, progression free survival (PFS) was: 11.2, 6.4 and 9.0 months respectively. The most common adverse events were hematologic and infectious. In conclusion we found that our results correlated with those found in other studies in terms of response rates, survival measures, and also of treatment toxicity.

Simplified novel prognostic score for real-life older adults with multiple myeloma-registry-based analysis.

The main goal was to find a simple prognostic to evaluate overall survival of patients older than 65 years of age with myeloma. Retrospective registry-based analysis from the Registry of Monoclonal Gammopathies was conducted. Patients over 65 years with symptomatic myeloma were included. The four major parameters with impact on survival were identified: male gender, age > 75, creatinine > 152 µmol/L, and ECOG performance status 2-4. The patients were scored as good (0 points), intermediate good (1 point), intermediate poor (2 points), poor (3-4 points). Patients (1410 MM) were included. Median OS (months) was 65.7 (95% CI 49.8-81.7) for good, 51.0 (44.1-57.8) for intermediate good, 32.2 (26.2-38.2) for intermediate poor, and 18.9 (15.1-22.7) for poor. The differences in OS were statistically significant (p < 0.0001). Good score was used as reference for hazard ratios, which for each other score were 1.43 (1.09-1.84) for intermediate good, 2.58 (2.00-3.33) for intermediate poor, and 3.88 (2.94-5.10) for poor. Time to progression showed medians (months) 20.5 (17.4-62.4) for good, 19.3 (17.0-21.7) for intermediate good, 19.6 (16.2-23.0) for intermediate poor, and 13.0 (10.8-15.2) for poor. The suggested scoring system provides readily available information about the prognosis of MM patients above 65 years.

Current applications of multiparameter flow cytometry in plasma cell disorders.

This corrects the article DOI: 10.1038/bcj.2017.90.

[Mosquito-transmitted infections]. / Infektionen durch Stechmücken.

Mosquito-transmitted diseases represent one of the greatest health risks when traveling to tropical and sub-tropical countries. Only Japanese encephalitis and yellow fever can be avoided by inoculation, and only malaria can be prevented by chemoprophylaxis. Exposure prophylaxis is the only protection against all other mosquito-born diseases. These infections need to be carefully considered in the differential diagnosis of returning travelers, taking current epidemiology into account. This review discusses common infectious diseases and the options for their diagnosis and therapy.

Current applications of multiparameter flow cytometry in plasma cell disorders.

Multiparameter flow cytometry (MFC) has become standard in the management of patients with plasma cell (PC) dyscrasias, and could be considered mandatory in specific areas of routine clinical practice. It plays a significant role during the differential diagnostic work-up because of its fast and conclusive readout of PC clonality, and simultaneously provides prognostic information in most monoclonal gammopathies. Recent advances in the treatment and outcomes of multiple myeloma led to the implementation of new response criteria, including minimal residual disease (MRD) status as one of the most relevant clinical endpoints with the potential to act as surrogate for survival. Recent technical progress led to the development of next-generation flow (NGF) cytometry that represents a validated, highly sensitive, cost-effective and widely available technique for standardized MRD evaluation, which also could be used for the detection of circulating tumor cells. Here we review current applications of MFC and NGF in most PC disorders including the less frequent solitary plasmocytoma, light-chain amyloidosis or Waldenström macroglobulinemia.

Biobanking - the First Step to Successful Liquid Biopsy Experiments.

BACKGROUND: Archiving of biological materials in biobanks is considered to be the initial crucial part of research activities. Most often, biobanks are founded for research purposes since they allow collection of sufficient material for analysis of new or testing of previously identified biomarkers. Biobanking needs to quickly react to current needs of researchers as well as clinicians, it is not a rigid system. Laboratory analyses of monoclonal gammopathies are based on separation of plasma cells from bone marrow of patients. A specific problem is usually a lack of tumor cell fraction, which is due to location of tumor cell in bone marrow in combination with low infiltration. One of the challenges in clinical research is the necessity of changes in biobanking for samples allowing detection of minimal residual disease in the bone marrow but also from peripheral blood by the so-called liquid biopsies. AIM: The aim of this review is to show the importance of archiving biological material in the Czech Republic and to show concrete examples of its usage in hematooncology. CONCLUSION: A general problem in solving many research questions is the availability of a critical amount of specimens for statistical analysis. Obtaining critical amount of specimens of biological material can be quickly archived by cooperation of biobanks sharing both methodological standards and informations about the availability of samples for research projects.Key words: archiving - biological material - informed consent - multiple myeloma - plasma cells.

Whole Exome Sequencing of Aberrant Plasma Cells in a Patient with Multiple Myeloma Minimal Residual Disease.

Multiple myeloma is a plasma cell dyscrasia. It is the second most common hematological malignancy which is characterized by proliferation of clonal plasma cells producing harmful monoclonal immunoglobulin. Despite treatment modalities greatly evolved during the last decade, small amount of aberrant residual cells reside in patients after therapy and can cause relapse of the disease. Characterization of the residual, resistant clones can help to reveal important therapeutic targets for application of effective and precious treatment. We use CD38, CD45, CD56 and CD19 sorted aberrant plasma cells to perform next generation sequencing of their exome. Among the 213 genes in which at least one variant was present, the most interesting was found gene NRAS, one of the most often mutated gene in multiple myeloma, and homologs of 88 gene panel previously used for multiple myeloma sequencing among which was a gene previously identified as gene meaningful in bortezomib resistance. Nevertheless, the results of next generation exome sequencing need to be interpreted with caution, since they rely on bioinformatical analysis, which is still being optimized. The results of next generation sequencing will also have to be confirmed by Sanger sequencing. Final results supported by larger cohort of patients will be published soon.Key words: multiple myeloma - minimal residual disease - exome - next generation sequencing.

Diagnostic Tools of Waldenströms Macroglobulinemia - Best Possibilities for Non-invasive and Long-term Disease Monitoring.

Waldenströms macroglobulinemia (WM) is a B-cell malignancy characterized by high level of monoclonal immunoglobulin M (IgM) paraprotein in blood serum and associated with the bone marrow infiltration by malignant cells with lymphoplasmacytic differentiation. WM remains incurable advances in therapy. Most of WM cases are associated with a somatic point mutation L265P in MYD88. Significantly higher risk of progression from the IgM monoclonal gammopathy of undetermined significance (IgM MGUS) to WM for patients with mutated MYD88 gene suggests that this mutation is an early oncogenic event and plays a central role in development of malignant clones. The second, most prevalent mutation in WM is found in the CXCR4 gene and is often associated with drug resistance and aggressive disease presentation. Therefore, detection of these mutations (MYD88L265P and CXCR4S338X) could be useful diagnostic and prognostic tool for the patients with WM. While detection of these mutations in bone marrow sample is common, the aim of our study was to compare sensitivity of detection of mutation from different cell fraction from peripheral blood and bone marrow. The results show possibility to describe MYD88 and CXCR4 mutation status even from peripheral blood sample (sensitivity for MYD88L265P was 100%, for CXCR4S338X 91%), which significantly facilitate material collection. Moreover, comparable detection sensitivity of these mutations in bone marrow and peripheral blood samples examined before and during the therapy offers a promising tool for more routine diagnostic and monitoring of disease progression.Key words: Waldenström macroglobulinemia - hematology - neoplasms - lymphoma - mutation - MYD88 - CXCR4.

Biobanking strategy and sample preprocessing for integrative research in monoclonal gammopathies.

AIMS: Some types of monoclonal gammopathies are typified by a very limited availability of aberrant cells. Modern research use high throughput technologies and an integrated approach for detailed characterisation of abnormal cells. This strategy requires relatively high amounts of starting material which cannot be obtained from every diagnosis without causing inconvenience to the patient. The aim of this methodological paper is to reflect our long experience with laboratory work and describe the best protocols for sample collection, sorting and further preprocessing in terms of the available number of cells and intended downstream application in monoclonal gammopathies research. Potential pitfalls are also discussed. METHODS: Comparison and optimisation of freezing and sorting protocols for plasma cells in monoclonal gammopathies, followed by testing of various nucleic acid isolation and amplification techniques to establish a guideline for sample processing in haemato-oncology research. RESULTS: We show the average numbers of aberrant cells that can be obtained from various monoclonal gammopathies (monoclonal gammopathy of undetermined significance/light chain amyloidosis/multiple myeloma (MM)/MM circulating plasma cells/ minimal residual disease MM-10 123/22 846/305 501/68 641/4000 aberrant plasma cells of 48/30/10/16/37×106 bone marrow mononuclear cells) and the expected yield of nucleic acids provided from multiple isolation kits (DNA/RNA yield from 1 to 200×103 cells was 2.14-427/0.12-123 ng). CONCLUSIONS: Tested kits for parallel isolation deliver outputs comparable with kits specialised for just one type of molecule. We also present our positive experience with the whole genome amplification method, which can serve as a very powerful tool to gain complex information from a very small cell population.

[Daratumumab - Hope for Myeloma Patients, a Challenge for Clinical Laboratories]. / Daratumumab - nadeje pro myelomové pacienty, výzva pro klinické laboratore.

Monoclonal antibodies represent a standard part in the treatment of oncologic patients, but their efficacy in multiple myeloma used to be unsatisfactory. Daratumumab monotherapy was approved by the American FDA in 2015, after unprecedented results were obtained in a heavily pre-treated group of patients. In 2016 daratumumab was approved in combination with lenalidomide and dexamethasone, or bortezomib and dexamethasone, for the treatment of myeloma patients who have received at least one prior therapy.The toxicity of the drug is low, and is dominated by infusion-related reactions in more or less half of patients. The development as well as the management of these sometimes urgent reactions is described in depth in this review. As multiple myeloma is characterized by the presence of paraprotein (monoclonal antibody) and CD38 is a ubiquitous antigen, several unexpected complications have been reported during the administration of the drug. In this review, we aim to describe and offer some solutions for the complications that may be encountered during daratumumab treatment, such as interference with serum protein electrophoresis and immunofixation assays that may confuse the assessment of the hematological response, interference with blood compatibility testing that may cause a delay in the delivery of compatible transfusions, and difficulties that may occur in flow cytometric analysis of minimal residual disease. Because of the high activity of daratumumab and its expected widespread use, clinicians should be aware of its side effects and their management. It is also very important to inform colleagues in clinical laboratories about the initiation of daratumumab treatment in particular patient.Key words: multiple myeloma - daratumumab - infusion related reaction - flow cytometry - transfusionThis work was supported by the Czech Ministry of Education, Youth and Sports (project no. IRP- 201550) and by the Czech Ministry of Health (15-29667A).The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study.The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.Accepted: 22. 8. 2016Submitted: 12. 5. 2016.

Proteasome inhibitors in AL amyloidosis: focus on mechanism of action and clinical activity.

Proteasome inhibitors are the backbone in the treatment of multiple myeloma with 3 of its representatives (bortezomib, carfilzomib, and ixazomib) having already been approved. There is a different situation altogether in the treatment of amyloid light chain (AL) amyloidosis where owing to the rarity of this entity neither of these drugs has currently gained approval. Amyloid light chain plasma cells are possibly more vulnerable to bortezomib than myeloma plasmocytes because of a slightly distinct mechanism of action, which is described in depth in this manuscript. Bortezomib is highly active and rapidly effective as a single agent and even more potent in combination with dexamethasone and alkylators. Bortezomib-based regimens have become a standard part of the initial treatment of AL amyloidosis in the majority of centers. We have reviewed all available data on bortezomib in various combinations and settings. Carfilzomib seems to be effective but also toxic in these fragile patients with a high rate of cardiac events. Oral ixazomib has shown a surprisingly high efficacy with manageable toxicity and has received the Food and Drug Administration Breakthrough Therapy designation in 2014 for relapsed AL amyloidosis patients. In this review we have comprehensively described the current available knowledge of these 3 proteasome inhibitors and their use in AL amyloidosis.

Immunomodulatory drugs in AL amyloidosis.

Immunoglobulin light chain amyloidosis (AL amyloidosis) is indeed a rare plasma cell disorder, yet the most common of the systemic amyloidoses. The choice of adequate treatment modality is complicated and depends dominantly on the risk stratification of these fragile patients. Immunomodulatory drugs (IMiDs) are currently used in newly diagnosed patients as well as in salvage therapy in relapsed/refractory patients. IMiDs have a pleiotropic effect on malignant cells and the exact mechanism of their action has been described recently. Thalidomide is the most ancient representative, effective but toxic. Lenalidomide seems to be more effective, nevertheless the toxicity remains high, especially in patients with renal insufficiency. Pomalidomide is the newest IMiD used in this indication with a good balance between efficacy and tolerable toxicity and represents the most promising compound. This review is focused on the evaluation of all three representatives of IMiDs and their roles in the treatment of this malignant disorder.

PD-1/PD-L1 inhibitors in multiple myeloma: The present and the future.

The introduction of PD-1/PD-L1 pathway inhibitors has marked a significant milestone in the treatment of various types of solid tumors. The current situation in multiple myeloma (MM) is rather unclear, as distinct research groups have reported discordant results. This discrepancy dominantly concerns the expression of PD-1/PD-L1 molecules as well as the identification of the responsible immune effector cell population. The results of monotherapy with PD-1/PD-L1 inhibitors have been unsatisfactory in MM, suggesting that a combination approach is needed. The most logical partners are immunomodulatory agents as they possess many synergistic effects. We are also proposing other rational and promising combinations (e.g., daratumumab, ibrutinib, anti-CD137) that warrant further investigation.

Trends in the epidemiology of dengue fever and their relevance for importation to Europe.

Dengue fever continues to spread globally, causing major epidemics and putting major strain on health systems in affected countries. For imported dengue in Europe, south east Asia is the most important region of origin, followed by Latin America, the Indian subcontinent, the Caribbean, and Africa. Information regarding mosquito protective measures is highly recommended for all travellers to affected areas.

European cluster of imported falciparum malaria from Gambia.

A cluster of 56 patients returning from Gambia with falciparum malaria has been noted in several countries of the European Union since September this year. TropNetEurop, the European Network on Imported Infectious Disease Surveillance, collected and reported the cases. Lack of awareness and, consequently, of prophylactic measures against malaria were apparent in the majority of patients.

Randomized, double-blind, placebo-controlled phase 3 trial of the safety and tolerability of IC51, an inactivated Japanese encephalitis vaccine.

BACKGROUND: Japanese encephalitis (JE) is the most important mosquito-borne viral encephalitis and has a high case fatality rate. It is caused by Japanese encephalitis virus. Improved vaccines are urgently needed for residents in countries of endemicity, travelers, and the military. The aim of the present trial was to evaluate the safety and tolerability of IC51, Intercell's Vero cell-derived, purified, inactivated JE vaccine. METHODS: This was a randomized (3:1), double-blind, placebo-controlled, multicenter phase 3 trial. Healthy subjects were randomized to receive 2 doses of IC51 (n=2012) or placebo (n=663) at a 4-week interval. Adverse events following immunization (AEFI) were documented over a period of 2 months. RESULTS: The rate of severe AEFI was similar in the IC51 group (0.5%) and the placebo group (0.9%). The rate of medically attended AEFI and all AEFI was also similar in the IC51 group and the placebo group. The same applied for all adverse events, including local and systemic tolerability. Importantly, there were no signs of acute allergic reactions. CONCLUSION: The Intercell JE vaccine IC51 had a safety profile similar to that of placebo. These data, together with the immunogenicity data from a recent phase 3 trial, form the basis of application for licensure of this vaccine. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00605058.