Single agent daratumumab in advanced multiple myeloma possesses significant efficacy even in an unselected "real-world" population.

OBJECTIVE: The treatment of relapsed and refractory multiple myeloma (RRMM) remains challenging. The outcomes in highly pretreated populations are unsatisfactory and there is urgent need for novel and safe therapeutic approaches. Recently, daratumumab has been approved for RRMM with promising results even in monotherapy. The aim of this study was to assess the efficacy of single agent daratumumab outside a clinical trial. PATIENTS AND METHODS: 14 patients with RRMM and significant pretreatment (median 4.5 previous lines) entered a specific healthcare program and received treatment with single agent daratumumab. They were followed for therapeutic response based on IMWG criteria, and incidence of adverse events. The data were collected using the Registry of Monoclonal Gammopathies. RESULTS: The overall response rate was 38.5%. 23.1% of patients reached very good partial response, 15.4% reached partial remission, 15.4% had minimal response, 38.5% had stable disease and 7.7% had progressive disease. The median progression free survival was 4.6 months and median overall survival was not achieved. The toxicities were mostly mild, only infectious complications and hematological toxicity reached grade III. CONCLUSION: We conclude that daratumumab has significant activity in highly pretreated RRMM even as a single agent, with an acceptable toxicity profile and survival impact.

Cardiac amyloidosis: from clinical suspicion to morphological diagnosis.

Amyloidosis is a heterogeneous group of diseases characterised by extracellular accumulation of amyloid in various tissues and organs of the body, leading to alteration and destruction of tissues. Heart involvement is the most important prognostic factor in patients with systemic amyloidosis and the diagnosis and typing of amyloid must be made properly. The clinical picture shows congestive heart failure with predominant right-sided heart failure symptoms in fully developed disease, various types of arrhythmias and characteristic electrocardiography and echocardiography findings. Blood and urine monoclonal protein studies and cardiac biomarkers belong to the spectrum of standard laboratory examinations. Cardiac cardiomyopathy is connected with amyloid based on immunoglobulin light chains, serum amyloid A, transthyretin, atrial natriuretic factor or apolipoprotein A1. In the routine diagnostic algorithm, biopsy specimens are examined using special histological staining, immunohistochemistry and immunofluorescence; proteomic analysis is only performed in specialised centres.

Serum protein fingerprinting by PEA immunoassay coupled with a pattern-recognition algorithms distinguishes MGUS and multiple myeloma.

Serum protein fingerprints associated with MGUS and MM and their changes in MM after autologous stem cell transplantation (MM-ASCT, day 100) remain unexplored. Using highly-sensitive Proximity Extension ImmunoAssay on 92 cancer biomarkers (Proseek Multiplex, Olink), enhanced serum levels of Adrenomedullin (ADM, Pcorr= .0004), Growth differentiation factor 15 (GDF15, Pcorr= .003), and soluble Major histocompatibility complex class I-related chain A (sMICA, Pcorr= .023), all prosurvival and chemoprotective factors for myeloma cells, were detected in MM comparing to MGUS. Comparison of MGUS and healthy subjects revealed elevation of angiogenic and antia-poptotic midkine (Pcorr= .0007) and downregulation of Transforming growth factor beta 1 (TGFB1, Pcorr= .005) in MGUS. Importantly, altered serum pattern was associated with MM-ASCT compared to paired MM at the diagnosis as well as to healthy controls, namely by upregulated B-Cell Activating Factor (sBAFF) (Pcorr< .006) and sustained elevation of other pro-tumorigenic factors. In conclusion, the serum fingerprints of MM and MM-ASCT were characteristic by elevated levels of prosurvival and chemoprotective factors for myeloma cells.

CD38-negative relapse in multiple myeloma after daratumumab-based chemotherapy.

We present a case report of a patient relapsing after anti-CD38 treatment (daratumumab). The phenotype of the disease changed during this treatment, and the myeloma clone became CD38 negative and daratumumab refractory. We expected clonal shift, however, based on immunophenotyping, cytogenetics and arrayCGH; the clone was identical as before daratumumab-based treatment with the exception of CD38 negativity. We suggest that the downregulation or loss of CD38 might be an epigenetic "escape mechanism" of malignant plasma cells from antibody-based treatment. The aim of our study was to point out the pitfalls of immunophenotyping and cytogenetics in both assessing the minimal residual disease and clone detection after monoclonal antibody-based therapy.

A first Czech analysis of 1887 cases with monoclonal gammopathy of undetermined significance.

INTRODUCTION: Monoclonal gammopathy of undetermined significance (MGUS) is a premalignant condition with a risk of malignant conversion. PATIENTS AND METHODS: With the aim to estimate the cumulative risk MGUS progression to hematologic malignancies, we analyzed a nationwide population-based cohort of 1887 MGUS patients from the Czech Registry of Monoclonal Gammopathies (RMG) between 2007 and 2013. RESULTS: During the follow-up period (median 4 years; range 0.6-34.8), progression to hematologic malignancies was observed in 8.6% (162 of 1887) of patients. Factors associated with progression were as follows: M-protein concentration ≥1.5 g/dL, pathological sFLC (<0.26 or >1.65) ratio, bone marrow plasma cells (BMPCs) in cytology >5%, immunoparesis, age ≥69 years, and the level of serum hemoglobin at baseline <12.0 g/dL. Combining these factors, we propose a new risk model (CMG model). The risk of progression at 10 years was 1.6%, 16.9%, 22.9%, 39.4%, and 52.3%, respectively, if 0 (reference group), one, two, three, or four to five risk factors are present (P<.001) with HR 63 times higher compared to the reference MGUS group. CONCLUSION: The new CMG model was established with an advantage for better identification of MGUS patients at low risk.

[Analysis of serum free light chains κ/λ ratio and heavy/light chain pairs of immunoglobulin to the stratification of multiple myeloma according to Mayo Stratification of Myeloma and Revised International Staging System]. / Analýza vztahu volných lehkých retezcu κ/λ a páru tezkých/lehkých retezcu imunoglobulinu ke stratifikaci mnohocetného myelomu podle Mayo Stratification of Myeloma and Revised International Staging System.

INTRODUCTION: Assessment of serum levels of free light chains (FLC-κ and FLC-λ) and recently heavy/light chain pairs of immunoglobulin (HLC-κ and HLC-λ) and their ratio (FLC-r and HLC-r) has significantly enriched traditional algorithm of multiple myeloma (MM) evaluation. The aim of the presented study was to assess the relationship of classical prognostic parameters of MM, standard FLC-κ/λ and HLC-κ/λ ratio ((s)FLC-r and (s)HLC-r), modified ratio of "involved/uninvolved" FLC and HLC ((m)FLC-r and (m)HLC-r ), the difference between "involved - uninvolved" FLC and HLC (FLC-dif. and HLC-dif.) to current stratification models of MM based on the result of cytogenetic analysis. PATIENTS AND METHODS: In a group of 97 patients with MM we assessed serum levels of FLC by FreeliteTM method, and we calculated (s)FLC-r, (m)FLC-r and FLC-dif. indices by HevyliteTM method. For cytogenetic analysis we used FICTION (fluorescence immunophenotyping and interphase cytogenetics as a tool for the investigation of neoplasms). For MM stratification we used standard staging systems according to Durie-Salmon (D-S) and International Staging System (ISS) as well as novel stratification systems based on the results of cytogenetic analysis, ie. "Mayo Stratification of Myeloma and Risk-Adapted Therapy" (mSMART) and "Revised International Staging System" (R-ISS). RESULTS: Stratification mSMART and R-ISS has significantly different representation of "standard" or "low-risk" (71, 15.5, 11.3 a 29.9 %), "intermediate risk" (15.5, 53.6, 34 a 33 %) and "high risk" patients (13.4, 30.9, 54.7 a 37.1 %) compared to standard staging systems. mSMART stratification was compared to prognostic factors of MM (Hb, albumin, ß(2)-M, creatinine and LDH), and the only significant relationship was found in the case of ß(2)-M, R-ISS had relationship only to Hb and creatinine. In the case of D-S staging we found significant relationship of stages 1-3 and substages A and B to the levels of (m)FLC-r, FLC-dif. and (m)HLC-r, ISS had moreover relationship to k HLC-dif. and MIg concentration. Analysis of mSMART stratification showed primarily significant relationship of risk categories 1-3 to (m)FLC-r and (s)HLC-r indices, and R-ISS to (m)HLC-r index and MIg concentration. In both cytogenetics-based stratifications there was a lack of relationship to (s)FLC-r, FLC-dif. and HLC-dif. indices. CONCLUSION: Comparison of the results of standard staging systems according to D-S and ISS with cytogenetics based models mSMART and R-ISS showed different representation of risk groups, and significantly different relationship to classical prognostic factors together with original relationship of sMART stratification to (m)FLC-r and (s)HLC-r, and R-ISS to (m)HLC-r and MIg concentration.

Molecular Cytogenetic Analysis of Chromosome 8 Aberrations in Patients With Multiple Myeloma Examined in 2 Different Stages, at Diagnosis and at Progression/Relapse.

BACKGROUND: The genome of multiple myeloma (MM) clonal plasma cells is characterized by genetic changes of prognostic importance. Disease progression is accompanied by a number of secondary chromosomal aberrations including chromosome 8. We focused on the detection of chromosome 8 aberrations in patients with MM who were examined at 2 different phases: diagnosis and progression/relapse. PATIENTS AND METHODS: A total of 62 patients with MM were examined at the time of diagnosis and at relapse/progression. The median age was 64 years (range, 39-78 years); the study included 29 males and 33 females. We analyzed bone marrow samples for detecting aberrations on chromosome 8 by the fluorescence immunophenotyping and interphase cytogenetics as a tool for the investigation of neoplasms (FICTION) and fluorescence in situ hybridization methods with specific probes. RESULTS: Chromosome 8 aberrations were detected in 24 (38.7%) patients at diagnosis and in 29 (46.8%) patients at progression/relapse. Only 5 (8%) patients developed additional chromosome 8 changes at progression/relapse. The aberrations were heterogeneous, involving numerical and structural changes of the MYC gene. Aberrations of the short arm of chromosome 8, involving the genes TRAIL-R1/-R2, were less frequent (4 of 62 patients, 6.4%). All aberrations of chromosome 8 were accompanied with additional changes and with an advanced clinical phase of the disease. This finding significantly influenced the overall survival of patients. CONCLUSION: In the current study, chromosome 8 aberrations were highly heterogeneous, were presented at diagnosis in patients with advanced clinical stage, and were associated with worse overall survival. We have not confirmed the increase of frequency aberration of chromosome 8 in disease progression. The findings demonstrate the importance of fluorescence in situ hybridization examination of chromosome 8 in newly diagnosed patients with MM.

Prospective comparison of conventional radiography, low-dose computed tomography and magnetic resonance imaging in monoclonal gammopathies.

AIMS: We carried out a prospective study in order to identify the best imaging approach for patients with newly diagnosed multiple myeloma (MM) and monoclonal gammopathy of undetermined significance (MGUS). METHODS: We assessed the extent of myeloma bone disease (MBD) in 112 individuals - 84 patients with MM and 28 individuals with MGUS. For the detection of osteolytic involvement we used whole-body magnetic resonance imaging (WB-MRI), low-dose computed tomography (LD-CT) and conventional radiography (CR). Each method assessed the presence of osteolytic involvement, compressive fractures and extramedullary involvement in the following regions: skull, spine and chest, pelvis and humerus and femur. We compared the difference in the number and extent of osteolytic involvement, especially the findings in CR negative patients. RESULTS: Conventional radiography showed no superiority in any of the evaluated regions, and failed in the detection of extramedullary massess and spine involvement. WB-MRI was best at imaging the spine including extramedullary involvement, however, detection of osteolytic lesions of the skull was limited in comparison with both CR and LD-CT. Both WB-MRI and LD-CT were comparable in imaging of lesions of pelvis, humerus, femur and the presence of extramedullary masses. LD-CT showed superiority in detection of skull lesions but lower sensitivity in spine compared to WB-MRI. CONCLUSIONS: Our results confirm that relying solely on CR in the diagnostics of MM is insufficient. We suggest that the most suitable method for primary assessment of osteolytic involvement in monoclonal gammopathies should include either whole-body MRI together with CR of the skull or, with an equivalent sensitivity, whole body LD-CT.

Prospective study of signalling pathways in myeloma bone disease with regard to activity of the disease, extent of skeletal involvement and correlation to bone turnover markers.

AIMS: The aim of our study was to address the utility of serum levels of selected parameters of myeloma bone disease (MBD) signalling with regard to the pathogenesis of multiple myeloma (MM), activity, markers of bone turnover and extent of skeletal changes. PATIENTS AND METHODS: We assessed prospectively 77 individuals with monoclonal gammopathies - 46 patients with active MM (AMM), 12 patients with smouldering MM (SMM) and 19 individuals with monoclonal gammopathy of undetermined significance (MGUS) to determine the role of HGF, MIP-1α, Syndecan-1, osteoprotegerin, Activin A, DKK1, Annexin A2 and NF-κB. RESULTS: We found significant differences of most of the parameters between MGUS and AMM, and with respect to the activity of MM assessed by International Staging System. Most of the parameters of MBD signalling correlated with traditional markers of bone turnover. CONCLUSIONS: All the signalling pathways were activated in MM with more pronounced osteoclastogenesis in comparison with bone formation but not in MGUS regardless of its risk category, suggesting that MBD is not activated in MGUS until the process of transformation into MM. The parameters of MBD signalling might precede the increase of conventional parameters of bone turnover suggesting their possible role in early indication of anti-resorption therapy.

Relationship of differences in immunoglobulin heavy/light chain pairs (Hevylite), selected laboratory parameters and stratification systems in different immunochemical types of multiple myeloma.

BACKGROUND AND AIMS: Advances in the diagnosis and treatment of multiple myeloma (MM), place increasing demands on accurate stratification of patients as the starting point for optimal individualized therapy. The present study focused on assessing the association between HLC levels and the HLC-r to parameters of MM activity, prognosis and tumor mass volume.The objective was to assess the correlation of immunoglobulin (Ig), heavy/light chain (HLC) pairs (IgG-κ and-λ, IgA-κ and -λ HLC) and the ratio of monoclonal involved-HLC (i-HLC) to polyclonal uninvolved (u-HLC) Ig concentrations assessed by the Hevylite(TM) method with the free light chain κ/λ ratio (FLC-r), selected prognostic laboratory parameters i.e. Hb, platelets, albumin, ß2-microglobulin (ß2-M), Ca, lactate dehydrogenase (LDH), creatinine and the Durie-Salmon (D-S) and International Staging System (ISS), stages (1-3) for MM. METHODS: Hevylite assays were done on the sera of 132 MM patients at the time of diagnosis (IgG 94, IgA 38). HLC-r was calculated in the case of i-HLC-κ from the i-HLC-κ/u-HLC-λ ratio and for i-HLC-λ from the i-HLC-λ/u-HLC-κ ratio. D-S and ISS stages were evenly distributed. RESULTS: Md IgG-κ HLC-r was 64.8 (2.7-2222) and of IgG-λ HLC-r 49.6 (0.7-465.1), in the case of IgA-κ, Md HLC-r was 408.9 (3.4-3966) and for IgA-λ HLC-r the Md was 180.0 (0.1-3110). Normal levels of HLC pairs and HLC-r did not always rule out the diagnosis of MM. HLC-r correlated with FLC-r in IgG (r = 0.244, P = 0.018), but not in the IgA type. For IgG, HLC-r values were significantly different in patients with abnormal vs normal levels of Hb (P < 0.0001), albumin (P < 0.043), ß2-M (P < 0.0001) and creatinine (P = 0.034) but not thrombocyte count, Ca or LDH. For the IgA isotype, we found a significant difference in HLC-r values only for thrombocyte count (P = 0.026) and ß2-M (P = 0.016) but not for Hb, albumin, Ca, LDH or creatinine. For the IgG isotype there was a significant relationship of HLC-r index to stages 1-3 (P = 0.038) and substage A vs B (P = 0.048) according to D-S, and with high significance to stages 1-3 according to ISS (P = 0.005) and between stages 1 vs 3 (P = 0.001). For the IgA isotype, we found significant differences in HLC-r only between stages 1-3 (P = 0.025) according to D-S but not in the case of ISS. There were no significant correlations between i-HLC Ig levels and D-S or ISS stages in both IgG-κ and λ and IgA-κ and λ. Exceptions were significant differences for stages 1 vs 3 (P = 0.012) and 2 vs 3 (P = 0.017) for the IgG-λ isotype. There were no correlations of the HLC-r and u-HLC levels for either D-S or ISS stratifications in all HLC isotypes. CONCLUSION: We found a significant positive contribution of HLC-r using the i-HLC/u-HLC ratio even in the case of i-HLC-λ i.e. i-HLC-λ/u-HLC-κ. Variable results for the relationship of important laboratory parameters and D-S and ISS stratifications (stage 1-3) to HLC-r values in IgG and IgA isotypes make separate interpretation of the Hevylite method results necessary in clinical practice.

[Analysis of serum levels of Dickkopf-1 (DKK-1) in monoclonal gammopathy of undetermined significance and multiple myeloma]. / Analýza sérových hladin Dickkopf-1 (DKK-1) u monoklonální gamapatie nejistého významu a mnohocetného myelomu.

BACKGROUND: Several recent studies aim at the detection of biological parameters that enable more precise diagnostics and stratification of monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma (MM). The objective of our study was to assess the potential contribution of serum levels of Dickkopf-1 (DKK-1) in MGUS and MM from the point of more specific differentiation of both conditions, and the relationship of DKK-1 to selected laboratory parameters, individual forms and clinical stages of both conditions. METHODS AND RESULTS: The analyzed cohort consisted of 46 individuals with MGUS and 152 patients with MM at the time of diagnosis. For the assessment of serum levels of DKK-1 we used ELISA method. We assessed also serum levels of free light chains (FLC) κ and λ using the Freelite system, and ß2-microglobulin (ß2-M) using the Immulite 1000 method. For statistical estimation we used: Pearson χ2-test, U-test according to Mann-Whitney and Kruskal-Wallis test. Our analysis revealed that there was no significant difference between the levels of DKK-1 in MGUS risk groups (0-3) and between the states with different FLC concentration including the κ/λ index of monoclonality. In MM there was a significant relationship of DKK-1 to the level of hemoglobin (p<0.008) but not to the levels of FLC, creatinine or ß2-microglobulin. Within the Durie-Salmon staging system, there were significant differences of DKK-1 between the stages I vs. III (p=0.001) and I vs. II+III (p=0.002). In the International Staging System (ISS) there were significant differences only between stages 1 vs. 2+3 (p=0.045). Although there was no overall significant difference of DKK-1 levels between MGUS and MM, there was a difference between MGUS vs stage III (p=0.001) and II+III (p=0.001) according to Durie-Salmon, and also MGUS vs. stage 2 (p=0.005) and vs. stages 2+3 (p=0,012) according to ISS. There were no significant differences in DKK-1 between MGUS and initial/asymptomatic form of MM (stage I). CONCLUSION: Although there was a significant difference of serum levels of DKK-1 between MGUS and initial/asymptomatic stage of MM when compared to advanced stage MM, and in patients with different Hb levels, we do not find the evaluation of serum levels of DKK-1 useful for routine discrimination of MGUS and MM, and for the specification of temporary stratification systems.

Subcutaneous bortezomib in multiple myeloma patients induces similar therapeutic response rates as intravenous application but it does not reduce the incidence of peripheral neuropathy.

OBJECTIVE: Subcutaneous (SC) application of bortezomib has been recently introduced as a new application route in multiple myeloma (MM) patients. We performed an analysis to compare the outcomes of bortezomib-based therapy in multiple myeloma (MM) patients treated using either intravenous (IV) or subcutaneous (SC) route of administration. PATIENTS AND METHODS: During January 2012 through December 2013, we performed a retrospective analysis of 446 patients with MM treated with bortezomib-based regimens (either once weekly - 63% or twice weekly - 27%) in both, the first line setting, and in relapse, with separate analysis of patients undergoing autologous stem cell transplantation. We assessed the response rates and toxicity profiles in both, IV and SC route of bortezomib administration. RESULTS: The response rates in both IV and SC arm were similar with overall response rate 71.7% vs 70.7%, complete remissions in 13.9% vs 8.6%, very good partial remissions in 30.8% vs 34.5% and partial remissions in 27% vs 27.6%. The most frequent grade ≥ 3 toxicities were anemia, thrombocytopenia and neutropenia, with no significant differences between IV and SC group. There were no significant differences in the rate of peripheral neuropathy (PN). PN of any grade was present in 48% in the IV arm and in 41% in the SC arm. PN grade ≥ 2 was present in 20% vs 18% and PN grade ≥ 3 was present in 6% vs 4%. CONCLUSIONS: We conclude that subcutaneous application of bortezomib has similar therapeutic outcomes and toxicity profile as intravenous route of application. In our cohort there was no difference in the incidence of PN, suggesting that PN is dose dependent and might be reduced by lower intensity schemes rather than by the route of administration.

[The role of the assessment of heavy/light chain pairs of immunoglobulin in monoclonal gammopathies]. / Význam vysetrení páru tezkých/lehkých retezcu imunoglobulinu u monoklonálních gamapatií

The aim of the paper is to inform about the contribution of novel, highly sensitive analytic technique for the assessment of serum immunoglobulins (Hevylite), enabling separate quantitative assessment of heavy/light chain pairs of immunoglobulin (HLC), i. e. the monoclonal ("involved") and polyclonal ("noninvolved") isotype including their ratio (HLC-r) in monoclonal gammopathies. We particularly target the characteristics of this technique, the compari-son of its clinical contribution with standard methods used in the diagnostics, course and the detection of relapse and progression of the disease, as well as the stratification, assessment of therapeutic outcome and prognosis in monoclonal gammopathy of undetermined significance, multiple myeloma, Waldenström´s macroglobulinemia, systemic AL-amyloidosis and some non-Hodgkin lymphomas. Present results show that in comparison with existing routinely used techniques the Hevylite method enriches clinical practice with the assessment of serum levels of "uninvolved" Ig. It enables the evaluation of the depth of "immunoparesis", and the determination of HLC-r index that is needful for the stratification of MM into "risk cohorts". It also contributes to prognostic assessment and improvement of the evaluation of the depth of therapeutic response. In MGUS individuals the HLC-r index provides information about the risk of malignant transformation. We await the results of ongoing validation studies that are expected to provide specific indications for Hevylite technique for MG in routine practice.

Analysis of thymidine kinase serum levels by novel method DiviTum in multiple myeloma and monoclonal gammopathy of undetermined significance - comparison with imaging methods 99mTc-MIBI scintigraphy and 18F-FDG PET/CT.

AIMS: The study aimed at comparing two methods for evaluating thymidinekinase TK in serum - an older RIA method and novel DiviTum - in patients with MM and MGUS, and also comparing them with biochemical markers and degree of activity evaluated by imaging methods 99mTc-MIBI scintigraphy and 18F-FDG PET/CT. METHODS: Serum thymidinekinase TK levels were evaluated by DiviTum and an RIA method (TK REA kit by Immunotech);The study analyzed correlation of TK activity in serum with biochemical markers reflecting activity of MM: ß2-m, LDH, the ratio of kappa to lambda (κ/λ) free light chains and percentage of bone marrow plasma cells (BMPC). 99mTc-MIBI scintigraphy and 18F-FDG PET/CT were performed at the time of diagnosis. The degree of activity was expressed semiquantitatively. Scans were classified as 0 (normal activity), 1 (diffuse positivity) or 2 (focal positivity). RESULTS: We found a strong positive correlation between TK in serum evaluated by DiviTum and by TK REA.. The DiviTum analytic method extended the detection range and was able to detect higher levels of TK than the RIA method. DiviTum technique found positive correlation with ß2-m (r = 0.497) and LDH (r = 0.502) and moderate positive correlation with BMPC (r = 0.368). Significantly higher TK values measured by TK REA and DiviTum in the group of patients with MM (stages I, II or III) than in those with MGUS. Increased TK levels were observed in MIBI- or PET/CT-positive patients. Analysis of repeated measurements of TK in serum during treatment of MM patients found a correlation between change in TK measured by DiviTum and LDH during treatment. CONCLUSIONS: Analysis revealed a significant correlation between TK in serum and LDH, ß2-m and BMPC. Increased levels of TK in serum were observed in MIBI- or PET/CT-positive patients. Combination of positivity of imaging methods which can localize active tumor lesions and increased levels of TK in serum can have an impact on decision-making and optimization of the therapeutic approach.

[Analysis of the relationship of heavy/light chain pairs of immunoglobulin (Hevylite) to the results of gel electrophoresis and nefelometric examination of serum proteins at the time of multiple myeloma diagnosis]. / Analýza vztahu sérových hladin páru tezkých/lehkých retezcu imunoglobulinu (Hevylite) k výsledkum standardní gelové elektroforézy a nefelometrického vysetrení bílkovin séra pri diagnóze mnohocetného myelomu.

BACKGROUND: The diagnostics and treatment of multiple myeloma (MM) requires precise analysis of serum immunoglobulins, which might be limited by the sensitivity of standard examination methods. Hevylite method enables quantitative analysis of heavy/light chain pairs (HLC) of normal and tumor IgG and IgA immunoglobulin and their ratio (HLC-r). The aim of the study was to assess the contribution of Hevylite method in the diagnostics of MM in comparison with nephelometry (NEF), standard protein electrophoresis (SPE), immunofixation electrophoresis (IFE) and the examination of serum free light chains (FLC) of immunoglobulin using Freelite test and heavy/light chain pairs of immunoglobulin (HLC) using Hevylite. METHODS: Using the methods Hevylite, NEF, SPE, IFE and Freelite, we examined a cohort of 134 individuals fulfilling the International Myeloma Working Group (IMWG) criteria. 96 patients were of IgG and 38 of IgA type. RESULTS: The levels of HLC-kappa (K) and HLC-lambda (L), as well as HLC-r were independent of age and gender. Abnormal HLC levels were present in 84-100%, pathological HLC-r was in 92-100% cases based on MIg isotype. We found strong positive correlation between IgG and IgA (NEF) and the sum of HLC IgG-K + IgG-L (Hevylite) (r = 0.80, p < 0.0001) and HLC IgA-K + IgA-L (r = 0.75, p < 0.0001). Very strong positive correlation was between the concentration of MIg (SPE) and the levels of HLC (Hevylite) in IgG-K (r = 0.73), IgG-L (r = 0.76), IgA-K (r = 0.70) and IgA-L (r = 0.89), p < 0,0001. Systematic difference between Hevylite vs. MIg (SPE) was confirmed by Bland-Altmann test in the case of HLC IgA-K and IgA-L (not HLC IgG-K and IgG-L), and in the correlation of HLC with IgG and IgA (NEF). The most significant correlation between SPE (patients with < 15 g/L) vs. Hevylite was found within the analysis of HLC IgG-K+ IgA-K (r = 0.85, p < 0.0001), and in the whole cohort of MM patients, i.e. IgG + IgA-kappa and lambda (r = 0.76, p < 0.0001), confirmed by Bland-Altmann test. Tight positive correlation was between HLC-r and index of monoclonality FLC-K/L in MM of IgG and IgA type MM (p < 0.0001). CONCLUSION: Hevylite method, especially the assessment of HLC-r of IgA type MM is more sensitive in comparison with SPE evaluated by NEF, and increases the diagnostic sensitivity and the extent of tumor mass examination. Despite its limitation in the case of high levels of IgG type MIg, Hevylite technique has a promising potential to enrich the standard analytic tools as it enables to assess the concentration and ratio of the levels of both tumor and physiological immunoglobulins e.g. depth of immunoparesis, valid especially in MM with low levels of MIg.

[Bortezomib-based therapy in patients with light chain deposition disease]. / Lécba bortezomibem u pacientu s onemocnením z depozice lehkých retezcu imunoglobulinu.

Light chain deposition disease (LCDD) is a rare systemic condition caused by monoclonal proliferation of terminally differentiated B-lymphocytes with production of free light chains and their deposition in kidneys or other organs. The aim of our study is to show the pitfalls of the diagnostics, and to demonstrate the effect of bortezomib-based therapy on a series of 4 patients with LCDD, from the point of hematological and organ therapeutic response. We include that bortezomib based treatment provides rapid and effective hematological response. It is, however, often accompanied by adverse events, especially within intensive treatment schedules. The most serious adverse effects includes peripheral neuropathy, which might be dose or treatment-limiting. Less intensive regimens ("bortezomib weekly") suggest an alternative with expectation of lower incidence of adverse effects. Autologous stem cell transplantation is a recommended and relatively safe approach in convenient candidates. Organ response is significantly delayed after hematological response, and organ damage by light chain deposits might not be fully reversible.

10 years of experience with thalidomide in multiple myeloma patients: report of the Czech Myeloma Group.

We analyzed 1156 multiple myeloma (MM) patients treated with thalidomide. The overall response rate was 63.6%, with complete remission in 13.4%. Combined regimens had better outcomes than thalidomide plus dexamethasone or single agent thalidomide. Thalidomide was not able to overcome adverse cytogenetics. Superior results were seen in patients undergoing subsequent autologous stem cell transplantation. The rate of adverse events was low. Thalidomide has a strong potential to improve response and survival measures in patients with standard risk MM. Combined regimens should be used, with lower doses of thalidomide. High risk myelomas should be treated individually.

Comparison of imaging methods in POEMS syndrome.

BACKGROUND: POEMS syndrome is a clinical condition with a very heterogeneous clinical manifestation. Its presentation as well as monitoring is complex and dependent on the clinician's experience. One of the leading presenting symptoms is based on evaluation of skeletal damage with typical osteosclerotic or mixed lesions. AIMS AND METHODS: Our aim was to compare the usefulness of different imaging methods in the diagnostics of POEMS syndrome, such as conventional radiography, densitometry, technetium scintigraphy, PET/CT scan, MRI and angiography on a series of three patients with POEMS syndrome with different clinical manifestations and course of disease. RESULTS: Our series demonstrates different types of skeletal involvement in POEMS syndrome. Although conventional X-ray is the imaging method mostly used for the evaluation, its sensitivity and specificity is low. Under specific conditions, other imaging methods should be considered, giving a more complex outlook of the disease's skeletal involvement. Nevertheless, FDG-PET/CT confirmed its superiority in defining both skeletal lesions as well as the activity of the neoplastic process. CONCLUSIONS: We conclude that the different manifestation of the disease implies the necessity of a complex evaluation of imaging methods in mutual concordance. FDG-PET/CT emerges as the most contributive method for the evaluation of both the extent and activity of the disease.