The spectrum of somatic mutations in monoclonal gammopathy of undetermined significance indicates a less complex genomic landscape than that in multiple myeloma.

Monoclonal gammopathy of undetermined significance is a pre-malignant precursor of multiple myeloma with a 1% risk of progression per year. Although targeted analyses have shown the presence of specific genetic abnormalities such as IGH translocations, RB1 deletion, 1q gain, hyperdiploidy or RAS gene mutations, little is known about the molecular mechanism of malignant transformation. We performed whole exome sequencing together with comparative genomic hybridization plus single nucleotide polymorphism array analysis in 33 flow-cytometry-separated abnormal plasma cell samples from patients with monoclonal gammopathy of undetermined significance to describe somatic gene mutations and chromosome changes at the genome-wide level. Non-synonymous mutations and copy-number alterations were present in 97.0% and in 60.6% of cases, respectively. Importantly, the number of somatic mutations was significantly lower in monoclonal gammopathy of undetermined significance than in myeloma (P<10-4) and we identified six genes that were significantly mutated in myeloma (KRAS, NRAS, DIS3, HIST1H1E, EGR1 and LTB) within the monoclonal gammopathy of undetermined significance dataset. We also found a positive correlation with increasing chromosome changes and somatic gene mutations. IGH translocations, comprising t(4;14), t(11;14), t(14;16) and t(14;20), were present in 27.3% of cases and in a similar frequency to myeloma, consistent with the primary lesion hypothesis. MYC translocations and TP53 deletions or mutations were not detected in samples from patients with monoclonal gammopathy of undetermined significance, indicating that they may be drivers of progression to myeloma. Data from this study show that monoclonal gammopathy of undetermined significance is genetically similar to myeloma, however overall genetic abnormalities are present at significantly lower levels in monoclonal gammopathy of undetermined significant than in myeloma.

Genomewide association study on monoclonal gammopathy of unknown significance (MGUS).

OBJECTIVES: To identify germ line variants contributing to the development of monoclonal gammopathy of undetermined significance (MGUS), an asymptomatic premalignant precursor for multiple myeloma (MM). METHODS: We conducted the first genomewide association study (GWAS) on MGUS on 243 German cases with a replication on 294 Czech cases. Identified loci were further analyzed in 1508 German MM patients. New MM loci recently reported in a meta-analysis were also tested in the MGUS GWAS. RESULTS: In GWAS, we identified 10 loci contributing to development of MGUS at P-value threshold of 10-5 . The Czech cohort gave support for two associations (6q26, rs6933936; 7p21.3 rs10251201). In GWAS, rs974120 (8p23.2) reached genomewide significance (P=2.94×10-9 ), with a nominal significance in MM. The locus of rs974120 shows marks of transcriptional activity in leukemia according to ENCODE data. rs10251201 (7p21.3), rs9318227 (13q22.1), and rs10405859 (19q13.32) were associated with markers related to leukemogenesis and immune and inflammatory responses. Two newly identified candidate loci for MM, rs1948915 (8q24.21) and rs8058578 (16p11.2), were nominally associated with MGUS. CONCLUSIONS: These data allow a cautious first proposal for a germ line architecture of MGUS with links to leukemia and autoimmune conditions, the latter agreeing with a family study showing clustering of MGUS with autoimmune diseases.

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.

Multicentered patient-based evidence of the role of free light chain ratio normalization in multiple myeloma disease relapse.

INTRODUCTION: The normalization of free light chain ratio (FLCr) has been introduced as a marker of stringent complete remission (CR) of multiple myeloma (MM). There is currently a lack of literature assessing the role of FLCr on MM disease progression and remission status. PATIENTS AND METHODS: A multicentered retrospective review of 125 patients with MM in CR and various FLCr values was completed. Parameters of interest included patient demographics, FLCr values, complete remission (CR)/relapse status, and time to progression (TTP). The FLCr values were recorded to provide time-dependent findings on the role of FLCr on progression-free survival and overall survival (OS). RESULTS: The mean follow-up time of 125 patients from five hospitals in the Czech Republic was 31 months. A total of 47.2% of patients relapsed (54 of 125) during the follow-up period. The median TTP of patients with normal FLCr (n = 66) was 54.4 and 40.2 months for patients with abnormal FLCr (n = 59) (P = 0.217). None of the patients reached median overall survival regardless of FLCr values (P = 0.821). In the subgroup of newly diagnosed patients after upfront autologous stem cell transplantation (ASCT), there were 55.6% of patients (35 of 63) with normal FLCr and 44.4% (28 of 64) with abnormal FLCr. A total of 34.9% of patients (22 of 63) relapsed in this subgroup. Within the abnormal FLCr patients, a median TTP was 56.3 months, but no median TTP was reached among the normal FLCr patients (P = 0.746). Median OS in patients with normal (nFLCr) and abnormal FLCr (aFLCr) was not reached (P = 0.787). CONCLUSION: We did not observe any benefit from FLCr normalization in CR in myeloma patients in terms of progression-free survival or overall survival.

Genomewide profiling of copy-number alteration in monoclonal gammopathy of undetermined significance.

Monoclonal gammopathy of undetermined significance (MGUS) is a benign condition with an approximate 1% annual risk of symptomatic plasma cell disorder development, mostly to multiple myeloma (MM). We performed genomewide screening of copy-number alterations (CNAs) in 90 MGUS and 33 MM patients using high-density DNA microarrays. We identified CNAs in a smaller proportion of MGUS (65.6%) than in MM (100.0%, P = 1.31 × 10-5 ) and showed median number of CNAs is lower in MGUS (3, range 0-22) than in MM (13, range 4-38, P = 1.82 × 10-10 ). In the MGUS cohort, the most frequent losses were located at 1p (5.6%), 6q (6.7%), 13q (30.0%), 14q (14.4%), 16q (8.9%), 21q (5.6%), and gains at 1q (23.3%), 2p (6.7%), 6p (13.3%), and Xq (7.8%). Hyperdiploidy was detected in 38.9% of MGUS cases, and the most frequent whole chromosome gains were 3 (25.6%), 5 (23.3%), 9 (37.8%), 15 (23.3%), and 19 (32.2%). We also identified CNAs such as 1p, 6q, 8p, 12p, 13q, 16q losses, 1q gain and hypodiploidy, which are potentially associated with an adverse prognosis in MGUS. In summary, we showed that MGUS is similar to MM in that it is a genetically heterogeneous disorder, but overall cytogenetic instability is lower than in MM, which confirms that genetic abnormalities play important role in monoclonal gammopathies.

Clinical characteristics and outcomes in risk-stratified patients with smoldering multiple myeloma: data from the Czech Republic Registry of Monoclonal Gammopathies.

Smoldering multiple myeloma (SMM) is an asymptomatic precursor to active multiple myeloma (MM). The aim of this study was to report clinical characteristics and outcomes of patients with SMM stratified based on their risk of progression to MM using the Mayo 20/2/20 criteria. Data were leveraged from the Czech Myeloma Group Registry of Monoclonal Gammopathies (RMG). Key outcomes included progression-free survival from SMM diagnosis to active MM diagnosis or death (PFS), progression-free survival from SMM diagnosis to progression on first line (1 L) MM treatment or death (PFS2), and overall survival (OS). Of 498 patients, 174 (34.9%) were classified as high risk and 324 (65.1%) as non-high risk. Median follow-up was approximately 65 months. During follow-up, more patients in the high-risk vs non-high-risk group received 1 L MM treatment (76.4% vs 46.6%, p < 0.001). PFS, PFS2, and OS were significantly shorter in high-risk vs non-high-risk patients (13.2 vs 56.6 months, p < 0.001; 49.9 vs 84.9 months, p < 0.001; 93.2 vs 131.1 months, p = 0.012, respectively). The results of this study add to the growing body of evidence that patients with high-risk vs non-high-risk SMM have significantly worse outcomes, including OS.

Similar efficacy of thalidomide- and bortezomib-based regimens for first relapse of multiple myeloma.

Many regimens containing novel drugs have been developed for multiple myeloma (MM). It is not yet clear whether some of the novel agents are better than others. In a retrospective study, we have analyzed the outcomes of patients with first relapse of MM treated with thalidomide-based (T) regimens (n=105) or bortezomib-based (B) regimens (n=106). Both T and B groups were comparable regarding basic clinical parameters and first-line therapies. Combination of thalidomide with an alkylating drug (A) and dexamethasone (D) was used in 91 cases, T with D in five cases, and T alone in nine cases. A combination of bortezomib with A and D was used in 58 patients, B with D or A in 40 patients, and B alone in eight patients. In the T group, ORR was 51%, median TTP from the start of treatment for relapse of 13.1 months, and median OS of 30.4 months. In the B group, ORR was 50% with median TTP of 16.7 months and median OS of 37.2 months. No significant differences in ORR (p=0.774), TTP (p=0.207), or OS (p=0.889) were observed between the two groups. In conclusion, T- and B-based regimens appear to be equally effective in the treatment of first MM relapse.

Gain of 1q21 is an unfavorable genetic prognostic factor for multiple myeloma patients treated with high-dose chemotherapy.

The prognostic significance of 1q21 gain, del(13)(q14), del(17)(p13), t(4;14)(p16.3;q32), and t(11;14)(q13;q32) detected by interphase fluorescein in situ hybridization (FISH) was studied in a cohort of 91 patients with newly diagnosed multiple myeloma (MM). 1q21 gain was detected in 37 of 91 patients (40.7%). In comparison with patients lacking 1q21 gain, patients with 1q21 gain had significantly shorter progression-free survival (PFS) (14.9 versus 27.4 months; P = .044) and worse 4-year overall survival (OS) (40.1% versus 76.2% of patients; P = <.001). PFS or OS were not influenced by the presence or absence of the other studied chromosomal abnormalities. Although the occurrence of 1q21 gain correlated with deletion of 13q14, the presence of 1q21 gain can be considered an independent prognostic factor, as no impact of del(13)(q14) as an isolated chromosomal abnormality on either PFS or OS has been observed. In comparison with patients lacking 1q21 gain, patients with 1q21 gain were significantly more likely to discontinue the preplanned treatment protocol because of disease progression or death. We conclude that 1q21 gain defines a prognostically unfavorable group of MM patients.

Real-world Outcomes of Multiple Myeloma: Retrospective Analysis of the Czech Registry of Monoclonal Gammopathies.

INTRODUCTION: Real-world data on patient outcomes and treatment patterns in multiple myeloma (MM) are limited. MATERIALS AND METHODS: The present noninterventional, observational, retrospective analysis of prospectively collected Czech patient medical record data from the Registry of Monoclonal Gammopathies estimated real-world outcomes in adults with a diagnosis of symptomatic MM made between May 2007 and June 2014. RESULTS: In total, 2446 patients had initiated first-line treatment. The median overall survival since the diagnosis (primary endpoint) was 50.3 months (95% confidence interval, 46.1-54.5 months) and decreased with each successive treatment line. A similar trend was observed for progression-free survival and the depth of response. In line with European guidelines and clinical practice, bortezomib-, thalidomide-, and lenalidomide-based regimens were most commonly used across all treatment lines (42.3%, 28.9%, and 18.4%, respectively). In the first line, bortezomib and thalidomide were used most often, with lenalidomide the most commonly used agent in the relapse setting (second to fourth lines). Exploratory analyses revealed that younger age (≤ 65 years), lower international staging system stage, and previous stem cell transplantation were associated with significant improvements in overall and progression-free survival, especially in the early treatment lines. CONCLUSION: The present study is the first analysis of Czech data from the Registry of Monoclonal Gammopathies, and it provides important insights into the real-world management of MM for physicians and healthcare providers.

Adjusted comparison of daratumumab monotherapy versus real-world historical control data from the Czech Republic in heavily pretreated and highly refractory multiple myeloma patients.

OBJECTIVES: We conducted an adjusted comparison of progression-free survival (PFS) and overall survival (OS) for daratumumab monotherapy versus standard of care, as observed in a real-world historical cohort of heavily pretreated multiple myeloma patients from Czech Republic. METHODS: Using longitudinal chart data from the Registry of Monoclonal Gammopathies (RMG) of the Czech Myeloma Group, patient-level data from the RMG was pooled with pivotal daratumumab monotherapy studies (GEN501 and SIRIUS; 16 mg/kg). RESULTS: From the RMG database, we identified 972 treatment lines in 463 patients previously treated with both a proteasome inhibitor and an immunomodulatory drug. Treatment initiation dates for RMG patients were between March 2006 and March 2015. The most frequently used treatment regimens were lenalidomide-based regimens (33.4%), chemotherapy (18.1%), bortezomib-based regimens (13.6%), thalidomide-based regimens (8.0%), and bortezomib plus thalidomide (5.3%). Few patients were treated with carfilzomib-based regimens (2.5%) and pomalidomide-based regimens (2.4%). Median observed PFS for daratumumab and the RMG cohort was 4.0 and 5.8 months (unadjusted hazard ratio [HR], 1.14; 95% confidence interval [CI], 0.94-1.39), respectively, and unadjusted median OS was 20.1 and 11.9 months (unadjusted HR, 0.61; 95% CI, 0.48-0.78), respectively. Statistical adjustments for differences in baseline characteristics were made using patient-level data. The adjusted HRs (95% CI) for PFS and OS for daratumumab versus the RMG cohort were 0.79 (0.56-1.12; p = .192) and 0.33 (0.21-0.52; p < .001), respectively. CONCLUSIONS: Adjusted comparisons between trial data and historical cohorts can provide useful insights to clinicians and reimbursement decision makers on relative treatment efficacies in the absence of head-to-head comparison studies for daratumumab monotherapy.

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.

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.

Complex karyotype and translocation t(4;14) define patients with high-risk newly diagnosed multiple myeloma: results of CMG2002 trial.

The prognostic impact of chromosomal abnormalities was evaluated by fluorescence in situ hybridization with cytoplasmic immunoglobulin light chain staining (cIg-FISH) and by classical metaphase cytogenetics in a cohort of 207 patients with newly diagnosed multiple myeloma who were treated with high-dose therapy followed by autologous stem cell transplantation in the CMG2002 clinical trial. The incidence of chromosomal abnormalities detected by FISH was as follows: 52.7% for del(13)(q14), 6.5% for del(17)(p13), 18.6% for t(11;14)(q13;q32), 22.8% for t(4;14)(p16;q32) and 45.7% for gain(1)(q21). Metaphase cytogenetic analysis revealed a complex karyotype in 19.1% and hyperdiploidy in 21.7% of patients. The overall response rate was not influenced by the presence of any studied chromosomal abnormality. Patients with a complex karyotype, those with translocation t(4;14) and those with gain of the 1q21 locus had a shorter time to progression (TTP) and overall survival (OS). Other genomic changes such as translocation t(11;14) and del(13q) had less impact on TTP and OS. In multivariate analysis, complex karyotype, translocation t(4;14) and ß(2)-microglobulin level > 2.5 mg/L were independent prognostic factors associated with poor overall survival. Their unfavorable prognostic impact was even more pronounced if they were present in combination. Patients with t(4;14) present together with a complex karyotype had the worst prognosis, with a median OS of only 13.2 months, whereas patients with a normal karyotype or karyotype with ≤ 2 chromosomal changes had the best outcome, with 3-year OS of 85.9%. In conclusion, complex karyotype, gain of 1q21 region and translocation t(4;14) are major prognostic factors associated with reduced survival of patients with newly diagnosed multiple myeloma treated with autologous stem cell transplantation.