ALBERT

Description: Introduction: Great progress achieved in treatment of multiple myeloma (MM) over the past decade changed overall perception of importance of minimal residual disease (MRD) assessment. Since new drugs induce deep responses, MRD must be evaluated using sensitive techniques, such as allele specific PCR (ASO-PCR), next-generation sequencing (NGS) or flow cytometry. MM is a genetically heterogeneous cancer of plasma cells characterized by multiple focal lesions in the bone marrow (BM). Hence, a single-site biopsy can create a sampling bias. In spite of this, BM samples are typically used for MRD analysis, but currently an alternative approach called liquid biopsies, which utilizes body fluids for analysis of various molecules and cells, is intensively studied. Cell-free DNA (cfDNA) as one type of the molecule which can be analyzed using liquid biopsy approach showed promising results previously. In our study, patient-specific, clonotypic rearrangement of immunoglobulin heavy chain (IgH) gene, identified in bone marrow samples, was used for qPCR analysis of cfDNA samples from peripheral blood. We demonstrate that dynamics and quantity of patient-specific, clonotypic IgH rearrangement found in cfDNA can predict the outcomes and response of MM patients. Methods: Total of 45 patients enrolled in the study. Samples of BM were collected at diagnosis, and CD138+ cell fraction was sorted using magnetic activated cell sorting. At diagnosis and at three-month intervals, samples of peripheral blood (PB) were collected for cfDNA extraction and analysis until a patient reached complete remission (CR). If CR was not reached, samples were collected for 24 months after diagnosis. Two more samples of PB were collected (CR+3, CR+6) if patients reached CR. Patient-specific VDJ rearrangement was identified using previously described PCR method from genomic DNA extracted from CD138+ cell fraction; based on the results, patient-specific primers and probes were designed for use in ASO-qPCR. Obtained data were evaluated by absolute and relative frequencies of categorical variables and median (minimum-maximum) of quantitative variables. Results: First, we assessed time to CR. Patients were classified according to the quantity of cfDNA measured at time of diagnosis into three groups: negative, PNQ (= positive non-quantifiable) and positive. As PNQ had a similar profile to negative-classified samples (in K-M plot), PNQ were grouped together with negative results except extremely high values (〉 5, n = 2) which were reclassified from PNQ to positive group. The Kaplan-Meier estimates at 12 months were reported and supplemented by the 95% confidence interval derived using Greenwood formula. The results show that significantly higher number of patients classified as negative or PNQ with quantity 〈 5 have reached CR in contrast to patients classified as positive or PNQ with quantity 〉 5. The same trend applies to association of quantity of tumor-specific cfDNA with time to CR where Cox proportional-hazards model was adopted. Patients classified as negative or PNQ with quantity 〈 5 have significantly increased chance of achieving CR (2.7 times) in comparison to patients classified as positive or PNQ with quantity 〉 5. Conclusion: Our results demonstrate that MM patient-specific cfDNA fragments are released into the bloodstream and that patients either with no or very few DNA fragments have a higher chance of achieving better treatment response eventually. Work was supported by grant AZV 17-29343A Disclosures Hajek: Amgen: Consultancy, Honoraria, Research Funding; Bristol-Myers Squibb: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding.

Description: Introduction: Multiple myeloma patients over the age of 65 represent the majority of myeloma population. The main goal was to evaluate treatment outcomes in terms of overall survival for elderly patients based on initial choice of anti-myeloma drugs, and to find potential factors affecting survival. Patients and Methods: This is a retrospective registry based analysis from the Registry of monoclonal gammopathies of the Czech Myeloma Group. Patients with multiple myeloma diagnosed between 2007-2016 over the age of 65 with symptomatic myeloma were included in the analysis. Basic demographic data and disease characteristics were obtained. The Kaplan-Meier estimates were completed by the Greenwood confidence interval. The log-rank test was used to estimate the statistical significance of the difference between the curves. The Cox proportional hazards model was performed to explore the univariate significance of risk factors. Results: Data from 1410 MM patients were obtained. Gender [HR 1.316 (1.124-1.541), p=0.001], age [above 75 vs. 66-75, HR 1.437 (1.221-1.692), p〈 0.001], creatinine levels [at cutoff 152 µmol/L, HR 1.613 (1.365-1.905), p〈 0.001] and ECOG performance status [0-1 vs. 2-4, 1.869 (1.594-2.191), p〈 0.001] were found to significantly affect overall survival. Moreover these risk factors have cumulative effect on overall survival of the patients. Overall survival of patients regardless to above mentioned risk factors treated with upfront bortezomib (N = 880) was median OS 40.4 months (CI: 36.1-44.7), patients treated with upfront thalidomide (N = 370) had median OS 48.1 months (CI: 41.0-55.2), for lenalidomide (N = 64) median overall survival was 53.2 months (CI: 44.6-61.8) and for combination of bortezomib and thalidomide (N = 46) 32.2 months (CI: 26.6-37.8). When any of these risk factors was present the OS in each group shortened. In the group of patients with no risk factors (N = 255) the median OS for bortezomib (N = 126) was not reached, for thalidomide (N = 96) the median OS was 66.3 months (CI: 43.1-89.6), for lenalidomide (N = 17) 71.1 months (CI: 44.8-97.4) and for combination of bortezomib and thalidomide (N=8) was not reached. In the group of patients with 1 risk factor (N = 514) the median OS for bortezomib (N = 303) was 46.1 months (CI: 36.2-56.1), for thalidomide (N = 141) 56.2 months (CI: 47.5-64.9), for lenalidomide (N = 29) 49.0 months (CI: 9.7-88.2) and for combination of bortezomib and thalidomide (N=20) was not reached. In the group of patients with 2 risk factors (N = 420) the median OS for bortezomib (N = 288) was 34.0 months (CI: 24.7-43.4), for thalidomide (N = 87) 31.9 months (CI: 22.8-40.9), for lenalidomide (N = 14) 33.2 months (CI: 0.0-67.6) and for combination of bortezomib and thalidomide (N=20) 29.4 months (CI: 7.6-51.1). In the group of patients with 3-4 risk factors (N = 221) the median OS for bortezomib (N = 163) was 19.2 months (CI: 14.9-23.5), for thalidomide (N = 46) 18.9 months (CI: 13.0-24.7), for lenalidomide (N = 4) 6.1 months (CI: 0.0-63.0) and for combination of bortezomib and thalidomide (N=3) 14.3 months (CI:-). Conclusion: The overall survival of patients above the age of 65 shows promising results with the use of novel agents. The treatment outcomes seem to be generally affected by overall condition, age and gender of the patient rather than treatment modality used upfront. Figure. Figure. Disclosures Hajek: Amgen: Consultancy, Honoraria, Research Funding; Bristol Myers Squibb: Consultancy, Honoraria; Takeda: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Novartis: Research Funding. Maisnar:Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees.

Description: Background Multiple myeloma (MM) is the second most common hematological malignancy characterized by plasma cell (PC) infiltration of the bone marrow. Unfortunately, better imaging techniques convey multiple reports about increased incidence of the so-called extramedullary disease of MM (EM), an aggressive, mostly resistant entity with poor prognosis for patients. EM probably develops because of 'bone marrow escape' of PC subclone that migrates out of the BM infiltrating soft tissues losing dependence on the BM microenvironment, either partially or completely. There are two types of EM - primary, found at the time of MM diagnosis, and secondary, found at the time of MM relapse. However, there are very few reports about EM. Aims This study aims to analyze risk factors connected to EM development. Methods Data from the Registry of Monoclonal Gammopathies (RMG) were analyzed. The RMG represents a database for collection of clinical data concerning diagnosis, treatment and follow-up of Czech MM and other monoclonal gammopathies patients. In total, data of 4985 MM patients were collected into the RMG database between 2007 and June 2017. Our analysis compared patients who developed EM at initiation of first or higher line of therapy with patients without EM during at least 5-year-long follow-up (patients who died earlier included). Logistic regression analysis was used to assess the association of baseline characteristics at MM diagnosis with EM occurrence at first line and relapse, respectively. Results In total, 4985 MM patients data were collected into the RMG database between 2007 and 2017. Patients were treated with bortezomib, lenalidomide, thalidomide, pomalidomide, ixazomib and daratumumab. Regardless of treatment, EM patients responded worse than MM patients did to any form of treatment. While primary EM patients had similar PFS as MM patients, OS was significantly worse (48.7 vs 60.6 months, resp.). Secondary EM patients did even worse, with PFS 8.7 months and OS 23.8 months only. We found 543 MM patients (10.9%) who developed EM during the entire follow-up. Out of these EM patients, we found 309 patients who were diagnosed with primary EM at initiation of first line of therapy. At initiation of 2nd line of treatment, we found 111 secondary EM patients. At 3rd, 4th and 5th, we found 61, 39 and 23 EM patients, resp. Finally, 309 patients who developed EM at initiation of 1st line and 234 patients who developed EM at initiation of further treatments were compared to 2092 patients who did not develop EM during the entire course of the disease. Overall, occurrence of EM at 1st or higher lines of treatment was associated with younger age, male sex, low ISS, D-S substage A, low B2 microglobulin, low creatinine, high hemoglobin, elevated thrombocytes, other types of M-Ig than IgG and presence of bone lesions. For EM cases found only at initiation of 1st line (primary EM), we found association with high ECOG status, low LDH, low M-protein quantity and low % of plasma cells infiltration in the bone marrow. For EM cases found at MM relapse (secondary EM), we found association with high D-S stage, high LDH, high CRP, high Ca, del13q and gain1q. Conclusion EM remains an aggressive disease with poor prognosis regardless of use of novel drugs. Surprisingly, in our group of patients, most EM disease developed early in the course of the disease - more than 60% at first relapse. We analyzed risk factors connected to development of EM and found that LDH, hemoglobin, thrombocytes and M-Ig status were associated with EM development. We suggest that in such patients, PET/CT or whole body MRI should be performed regularly to ensure early detection of EM. Grant support: AZV 17-29343A. Disclosures Maisnar: BMS: Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Hajek:Amgen: Consultancy, Honoraria, Research Funding; Bristol-Myers Squibb: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding.

Description: Immunoglobulin (Ig) secretion by terminally differentiated B-cells is important in the immune response to pathogens. Its over production is a defining characteristic of many B-cell malignancies, including Waldenström Macroglobulinemia (WM), where elevated IgM is associated with significant morbidity and poor prognosis. Thus, the identification and characterization of the mechanisms controlling Ig secretion are of great importance for the development of future therapeutic approaches for these diseases. Here, we define a novel pathway involving the oncogenic transcription factor, GLI2, modulating IgM secretion via regulation of IL-6 receptor alpha subunit (IL6Rα) expression in WM cells. We have previously identified components of the Hedgehog (HH)-GLI pathway as modulators of Ig secretion. Pharmacological (GANT61) and genetic (shRNA) inhibition of GLI proteins resulted in no significant effect on cell proliferation or viability, while there was a significant reduction in IgM secretion (60%) in BCWM.1 (p