Impact of high-risk classification by FISH: an eastern cooperative oncology group (ECOG) study E4A03

Cytogenetic Abnormalities in Multiple Myeloma: Incidence, Prognostic Significance, and Geographic Heterogeneity in Indian and Western Populations

Multiple myeloma (MM) is a genetically complex and heterogeneous neoplasm in which cytogenetics is a major factor playing an important role in the risk stratification of disease. High-risk MM based upon cytogenetic classification includes primary IGH translocations t(4;14), t(14;16), t(14;20), and secondary progressive aberrations such as gain/amp(1q), 1p deletion, del(17p), and hypodiploidy. Several studies have proved that interphase FISH can detect primary as well as secondary cryptic aberrations very efficiently in lowest 5-10% abnormal plasma cell population. The present large-scale study was undertaken to evaluate the incidence of cytogenetic abnormalities, to analyse the correlation of conventional karyotyping with FISH, and to seek the geographic heterogeneity in the incidence of primary as well as secondary aberrations in our Indian versus Western populations. We conducted prospective studies of 1,104 patients consecutively referred from the primary, secondary, and tertiary oncology centres from all over India. Interphase FISH was performed on isolated plasma cells. Karyotype analysis was done as per ISCN 2016 and 2020. FISH could detect cytogenetic abnormalities in 67.6% of the cases with an incidence of 59% non-hyperdiploidy. The incidence of IGH translocation was 26% versus literature frequency of 40-50% which was mainly due to a low incidence (6%) of t(11;14) in contrast to 15-20% in other series. Additionally, the association of secondary progressive aberrations in the hyperdiploid group rather than the non-hyperdiploid group in our patients is not a common finding. A biallelic inactivation of TP53 as an ultra-high risk factor was detected in old-aged patients. These observations disclose the novel findings and strongly indicate the racial disparity which leads to geographic heterogeneity. In contrast to FISH, conventional karyotyping could detect MM-related aberrations in 50% of cases, of which 44% revealed highly complex karyotypes with common aberrations of chromosome 1q. Overall, FISH was found to be a novel, easy approach with high success rate and capability of detection of all cytogenetic abnormalities that add valid information for the risk stratification of disease. This, in future, in combination with mutation profile and gene expression profile will help in further refinement of disease and identification of actionable targets.

Gene Expression Profiling in Multiple Myeloma: Redefining the Paradigm of Risk-Adapted Treatment

Multiple myeloma is a blood cancer characterized by clonal proliferation of plasma cells in the bone marrow. In recent years, several new drugs have been added to the therapeutic landscape of multiple myeloma, which have contributed to increased survival rates. However, while the use of therapeutics has evolved, there is still a group of high-risk patients who do not benefit from current treatment strategies. Risk stratification and risk-adapted treatment are crucial to identify the group of patients with urgent need for novel therapies. Gene expression profiling has been introduced as a tool for risk stratification in multiple myeloma based on the genetic make-up of myeloma cells. In this review we discuss the challenge of defining the high-risk multiple myeloma patient. We focus on the standardized analysis of myeloma cancer cells by gene expression profiling and describe how gene expression profiling provides additional insights for optimal risk-adapted treatment of patients suffering from multiple myeloma.

Prognostic gene expression analysis in a retrospective, multinational cohort of 155 multiple myeloma patients treated outside clinical trials

OBJECTIVES

Typically, prognostic capability of gene expression profiling (GEP) is studied in the context of clinical trials, for which 50%-80% of patients are not eligible, possibly limiting the generalizability of findings to routine practice. Here, we evaluate GEP analysis outside clinical trials, aiming to improve clinical risk assessment of multiple myeloma (MM) patients.

METHODS

A total of 155 bone marrow samples from MM patients were collected from which RNA was analyzed by microarray. Sixteen previously developed GEP-based markers were evaluated, combined with survival data, and studied using Cox proportional hazard regression.

RESULTS

Gene expression profiling-based markers SKY92 and the PR-cluster were shown to be independent prognostic factors for survival, with hazard ratios and 95% confidence interval of 3.6 [2.0-6.8] (P < .001) and 5.8 [2.7-12.7] (P < .01) for overall survival (OS). A multivariate model proved only SKY92 and the PR-cluster to be independent prognostic factors compared to cytogenetic high-risk patients, the International Staging System (ISS), and revised ISS. A substantial number of high-risk individuals could be further identified when SKY92 was added to the cytogenetic, ISS, or R-ISS. In the cytogenetic standard-risk group, ISS I/II, and R-ISS I/II, 13%, 23%, and 23% of patients with adverse survivals were identified.

CONCLUSIONS

For the first time, this study confirmed the prognostic value of GEP markers outside clinical trials. Conventional prognostic models to define high-risk MM are improved by the incorporation of GEP markers.

Multiple Myeloma: Clinical Updates from the American Society of Clinical Oncology Annual Scientific Symposium 2020

The novel clinical data for plasma cell neoplasms (smoldering myeloma, multiple myeloma, and AL amyloidosis) that were presented in the 2020 American Society of Clinical Oncology virtual scientific symposium are summarized here. Data from large phase-3 studies (CASSIOPEIA, ENDURANCE, and TOURMALINE-MM4 trials) and phase-2 studies (SWOG 1211, GMMG CONCEPT trials) for newly diagnosed multiple myeloma patients who are eligible for autologous stem cell transplantation are described. Updates from previous important studies for multiple myeloma (STaMINA) along with studies on three different chimeric antigen receptor (CAR-) T cell products are also described. Results of clinical studies involving the use of anti-myeloma drugs with novel mechanisms of action such as immunoconjugates, selinexor, venetoclax, monoclonal antibodies, and data on minimal residual disease (MRD) are discussed. These data provide an overview of the efficacy and safety of the various treatments in multiple myeloma and could lead to changes in our clinical practice, which could pave the path for a "cure" in myeloma.

High-risk myeloma and minimal residual disease postautologous-HSCT predict worse outcomes

The aim of our study was to determine the impact of high-risk disease (HRD) and MRD on outcomes in myeloma patients receiving bortezomib-based induction followed by autologous hematopoietic stem cell transplant (auto-HSCT). HRD included t(4:14), t(14;16), del 17p, del 1p and/or amplification 1q by cytogenetics/FISH; all others were standard-risk disease (SRD). A subset of 165 newly diagnosed myeloma patients in a 2:1 ratio of HRD:SRD was generated using propensity score based nearest neighbor matching. Multiparametric flow cytometry (MFC) was used to detect MRD after auto-HSCT in select patients. MRD+ status at 3 months post auto-HSCT (hazard ratio (HR = 4.23, p = .028) and HRD (HR = 1.72, p = .026) were associated with a shorter PFS. Similarly, MRD+ 3 months post auto-HSCT (HR = 6.93, p = .08) and HRD (HR = 3.54, p < .001) and were associated with a shorter OS. Despite bortezomib-based induction, upfront auto-HSCT, and use of maintenance therapy, PFS and OS remained worse in MRD+ and HRD patients.

Approach to the Older Adult With Multiple Myeloma

Multiple myeloma (MM) is a disease of aging adults, and numerous therapeutic options are available for this growing demographic. MM treatment of older adults continues to evolve and includes novel combinations, new generations of targeted agents, immunotherapy, and increasing use of autologous stem cell transplantation (ASCT). Understanding age-related factors, independent of chronologic age itself, is an increasingly recognized factor in MM survivorship, especially in understudied populations, such as octogenarians. Octogenarians have inferior survival that cannot be explained by cytogenetic profiles alone. Incorporating assessments of geriatric factors can provide guidance on how to intensify or de-escalate therapeutic options. Functional status, using objective testing, is superior to traditional metrics of performance status and should be implemented to optimize the risk-benefit ratio of ASCT. ASCT is feasible and cost-effective, and chronologic age should not exclude ASCT eligibility. Upfront ASCT remains the standard of care, in the context of a sequential approach that includes pre-transplantation induction and post-transplantation maintenance. High-risk MM is classically defined by disease characteristics, yet shifting frameworks suggest that the high-risk designation could refer to any patient subgroup who is at risk for poorer outcomes-beyond disease-focused outcomes to patient-focused outcomes. Defining the optimal treatment of subgroups of older patients with high-risk disease on the basis of chromosomal abnormalities is unexplored. Here, we review tools to assess individual health status, explore vulnerability in octogenarians with MM, address ASCT decision-making, and examine high-risk MM to understand factors that contribute to survival disparities for older adults with MM.

Clinical Utility of a Diagnostic Approach to Detect Genetic Abnormalities in Multiple Myeloma: A Single Institution Experience

Background

The identification of genetic abnormalities in patients with multiple myeloma (MM) has gained emphasis because genetics-based risk stratification significantly affects overall survival (OS). We investigated genetic abnormalities using conventional cytogenetics and FISH and analyzed the prognostic significance of the identified additional abnormalities in MM.

Methods

In total, 267 bone marrow samples were collected from February 2006 to November 2013 from patients who were newly diagnosed as having MM in a tertiary-care hospital in Korea. The clinical and laboratory data were retrospectively obtained. Cox proportional hazard regression was used to examine the relationship between clinical/genetic factors and survival outcome, using univariate and multivariate models.

Results

Using conventional cytogenetic analysis and FISH, 45% (120/267) and 69% (183/267) patients, respectively, were identified to harbor genetic abnormalities. In the univariate analysis, the following genetic variables were identified to affect OS: abnormal karyotype (P<0.001), aneuploidy (P=0.046), −13 or del(13q) (P=0.002), 1q amplification (P<0.001), and t(4;14) (P=0.020). In the multivariate analysis, the presence of −13 or del(13q) was the only significant genetic factor affecting OS (P=0.012) with a hazard ratio (HR) of 2.131 (95% confidence interval [CI], 1.185–3.832) in addition to the clinical factor of age (>65 years) (P=0.013) with an HR of 2.505 (95% CI, 1.218–5.151).

Conclusions

Our findings highlight the importance of applying a comprehensive approach for detecting genetic abnormalities, which could be closely associated with the prognostic significance of MM.

High-Throughput Copy Number Profiling by Digital Multiplex Ligation-Dependent Probe Amplification in Multiple Myeloma

Multiple myeloma (MM) is a genetically heterogeneous disease with a diverse clinical outcome. Copy number alterations (CNAs), including whole chromosome and subchromosomal gains and losses, are common contributors of the pathogenesis and have demonstrated prognostic impact in MM. We tested the performance of digital multiplex ligation-dependent probe amplification (digitalMLPA), a novel technique combining MLPA and next-generation sequencing, to detect disease-related CNAs. Copy number status at 371 genomic loci was simultaneously analyzed in 56 diagnostic bone marrow samples, which were also examined by conventional MLPA and interphase fluorescence in situ hybridization (iFISH). On average, digitalMLPA identified 4.4 subchromosomal CNAs per patient. The increased number of probes compared with conventional MLPA allowed a detailed mapping of CNAs, especially on chromosome 1, where 24 different patterns were observed in 38 patients harboring loss(1p) and/or gain(1q). iFISH, MLPA, and digitalMLPA results at loci investigated by multiple methods showed a congruency of 95%. Besides precise characterization of hyperdiploid karyotypes not efficiently achievable by iFISH or MLPA, digitalMLPA unraveled 156 CNAs not detected by the other two methods in 45 patients (80%). In addition, we provide proof of principle that digitalMLPA can detect known point mutations, in this case the BRAF^V600E. Our study demonstrates the robustness of digitalMLPA to profile CNAs and to screen point mutations in MM, which could efficiently be used in myeloma diagnostics.

Front-line therapies for elderly patients with transplant-ineligible multiple myeloma and high-risk cytogenetics in the era of novel agents

In multiple myeloma, certain cytogenetic abnormalities, such as t(4;14), t(14;16), and del(17p), are considered high risk and are associated with worse prognosis. Patients with these high-risk cytogenetic abnormalities, as well as those who are elderly and transplant ineligible, have not experienced the same degree of improved survival outcomes that other patients have seen with recent advances in the treatment of multiple myeloma. To date, no treatment regimen has demonstrated sustained and consistent survival benefits in elderly, transplant-ineligible patients with high-risk cytogenetic abnormalities and newly diagnosed multiple myeloma. Thus, there is an unmet need to identify effective treatment options for these patients and achieve outcomes parity with standard-risk patients. In this review, we assessed clinical trials of both doublet and triplet regimens for newly diagnosed multiple myeloma that included elderly, transplant-ineligible patients with high-risk cytogenetic abnormalities and that provided outcomes data stratified by cytogenetic risk status. We concluded that regimens containing an IMiD agent as the foundation of therapy, combined with agents that have synergistic mechanisms of action—including novel therapies—may in future investigations help overcome the poor prognosis of high-risk cytogenetic abnormalities in this vulnerable patient population.

Myeloma: management of the newly diagnosed high-risk patient

Although there have been many definitions for high-risk (HR) myeloma, most recent consensus for classifying risk in patients with newly diagnosed multiple myeloma (NMM) comes from the International Myeloma Working Group. This recently published revised International Staging System includes del(17p) or t(4;14) by fluorescence in situ hybridization, β-2 microglobulin, albumin, and lactate dehydrogenase. These elements should be captured in all NMM patients. The optimal treatments for HR myeloma have not been fully worked out; therefore, these patients should be considered for clinical trials. Outside of the trial setting for those patients who are not eligible for autologous stem cell transplantation (ASCT), a regimen with bortezomib, but not thalidomide, should be considered, with a duration of therapy of at least 1 year. The regimen with the best results to date is bortezomib, melphalan, and predisone. A nonthalidomide maintenance could also be considered. In patients who are eligible for ASCT, an induction regimen with bortezomib and an immunomodulatory drug should be administered for 3 to 6 months followed by 2 ASCTs. Finally, a consolidation/maintenance regimen containing at least 1 year of bortezomib should be administered followed by maintenance thereafter. For patient convenience, an oral agent that is not thalidomide could be prescribed as maintenance. Finally, in patients with HR myeloma, allogeneic SCT may be associated with reasonable outcomes, but this too will require further research.

High-risk multiple myeloma: a multifaceted entity, multiple therapeutic challenges

The term high-risk multiple myeloma is aimed to identify a heterogeneous group of patients who are more likely to progress and die early of their disease. Therefore, recognition of these patients is crucial. With the increase in the number of treatment options, the outcome for high-risk patients has probably improved, although the true extent of this improvement remains unknown, due to both the heterogeneous components of high-risk disease and its under-representation in clinical trials. In this article, we review the definitions of high-risk disease, emphasizing the fact that no single definition can represent the entire high-risk population. In the second part, we review the treatment options available for the management of high-risk myeloma as well as our general approach for high-risk disease. In light of the poor prognosis associated with high-risk myeloma, even in the current era, new approaches for the management of this subset of patients are needed.

Treatment of multiple myeloma with high-risk cytogenetics: a consensus of the International Myeloma Working Group

The International Myeloma Working Group consensus updates the definition for high-risk (HR) multiple myeloma based on cytogenetics Several cytogenetic abnormalities such as t(4;14), del(17/17p), t(14;16), t(14;20), nonhyperdiploidy, and gain(1q) were identified that confer poor prognosis. The prognosis of patients showing these abnormalities may vary with the choice of therapy. Treatment strategies have shown promise for HR cytogenetic diseases, such as proteasome inhibition in combination with lenalidomide/pomalidomide, double autologous stem cell transplant plus bortezomib, or combination of immunotherapy with lenalidomide or pomalidomide. Careful analysis of cytogenetic subgroups in trials comparing different treatments remains an important goal. Cross-trial comparisons may provide insight into the effect of new drugs in patients with cytogenetic abnormalities. However, to achieve this, consensus on definitions of analytical techniques, proportion of abnormal cells, and treatment regimens is needed. Based on data available today, bortezomib and carfilzomib treatment appear to improve complete response, progression-free survival, and overall survival in t(4;14) and del(17/17p), whereas lenalidomide may be associated with improved progression-free survival in t(4;14) and del(17/17p). Patients with multiple adverse cytogenetic abnormalities do not benefit from these agents. FISH data are implemented in the revised International Staging System for risk stratification.

Outcomes of primary refractory multiple myeloma and the impact of novel therapies

Over the past decade, use of novel agents, including immunomodulatory drugs (IMiDs) and proteasome inhibitors (PIs) has resulted in high response rates and improvement in overall survival (OS) for patients with multiple myeloma (MM); however, the prognostic significance of refractoriness to these agents when used as initial therapy has not been extensively studied. We reviewed the outcomes of 816 consecutive patients treated for MM at our institution since 2006 to evaluate the survival difference between those achieving at least a partial response (PR) to induction therapy and those who were primary refractory. The median OS from start of therapy was significantly shorter for the primary refractory group at 3.6 vs. 7.6 years for the responding patients (P < 0.001). The difference in median OS persisted when only patients receiving a novel agent as part of induction therapy were considered (3.6 vs. 7.9 years, P < 0.001) and in a 4-month landmark analysis (4.2 vs. 7.6 years, P < 0.001). The median OS for patients achieving a complete response (CR), very good partial response (VGPR), PR, or less than PR was not reached (NR), 6.1, 6.4, and 4.2 years from the 4-month landmark, respectively (P < 0.001). The comparatively poor outcomes of patients refractory to induction therapy in the current era of novel agents suggests that this high-risk subpopulation must be further studied for predictors of resistance and, when identified, should be targeted for clinical trials.

Prognostic indicators of lenalidomide for multiple myeloma: consensus and controversy

The long-term outcome of multiple myeloma (MM) has been greatly improved through new agents, one being lenalidomide (LEN). Based upon the findings of in vitro experiments, its mode of action against MM occurs through a combination of direct tumoricidal effects on myeloma cells, modulatory effects on tumor immunity and tumor microenvironment-regulatory effects. However, it has not been clearly defined whether the clinical response and long-term outcome of MM with LEN treatment truly reflect the mechanisms of action of LEN proposed by in vitro studies. To ascertain what is known and what remains to be elucidated with LEN, we review the current literature on the mode of action of LEN in association with myeloma pathophysiology, and discuss the prognostic indicators in the treatment of MM with LEN.

Front-line lenalidomide therapy in patients with newly diagnosed multiple myeloma

The availability of novel drugs with different and innovative mechanisms of action such as proteasome inhibitors such as bortezomib and immunomdulatory agents as thalidomide and lenalidomide have changed the landscape of the treatment of patients with newly diagnosed multiple myeloma, allowing the development of several new therapeutic regimens both for transplant-eligible and -ineligible patients. Among these new agents, lenalidomide has become one of the most commonly used in these patients. In this article, we review the current state-of-the-art of different induction and maintenance lenalidomide-containing regimens administered in transplant-eligible and -ineligible patients with newly diagnosed multiple myeloma. We also discuss the safety profile and potential long-term side effects of this drug and analyze its utility in certain subgroups of patients like those with high-risk disease or different degrees of renal impairment.

Proof of the concept to use a malignant B cell line drug screen strategy for identification and weight of melphalan resistance genes in multiple myeloma

In a conceptual study of drug resistance we have used a preclinical model of malignant B-cell lines by combining drug induced growth inhibition and gene expression profiling. In the current report a melphalan resistance profile of 19 genes were weighted by microarray data from the MRC Myeloma IX trial and time to progression following high dose melphalan, to generate an individual melphalan resistance index. The resistance index was subsequently validated in the HOVON65/GMMG-HD4 trial data set to prove the concept. Biologically, the assigned resistance indices were differentially distributed among translocations and cyclin D expression classes. Clinically, the 25% most melphalan resistant, the intermediate 50% and the 25% most sensitive patients had a median progression free survival of 18, 32 and 28 months, respectively (log-rank P-value  = 0.05). Furthermore, the median overall survival was 45 months for the resistant group and not reached for the intermediate and sensitive groups (log-rank P-value  = 0.003) following 38 months median observation. In a multivariate analysis, correcting for age, sex and ISS-staging, we found a high resistance index to be an independent variable associated with inferior progression free survival and overall survival. This study provides clinical proof of concept to use in vitro drug screen for identification of melphalan resistance gene signatures for future functional analysis.

Initial treatment of transplant-ineligible patients in multiple myeloma

Over two-thirds of newly diagnosed multiple myeloma are over 65 years. The treatment goals for the non-transplant-eligible patients should be to prolong survival by achieving the best response, while ensuring quality of life. New upfront treatment combinations based on first generation of novel proteasome inhibitors and immunomodulatory drugs plus alkylating agents, the historical platform, have significantly improved outcomes in the past 10 years. Other non-alkylator induction regimens, essentially lenalidomide plus low-dose dexamethasone are also available and provide a novel backbone that may be combined with novel second- and third-generation drugs. Data indicate that prolonged treatment extends the progression-free survival. In summary, this group requires individualized and dose-modified regimens to improve tolerability and efficacy, while maintaining their quality of life.

Lenalidomide in multiple myeloma-a practice guideline

BACKGROUND

Promising new drugs such as lenalidomide, an immunomodulatory agent, are available for the treatment of multiple myeloma. We describe the process of creating a provincial guideline for the use of lenalidomide, alone or in combination with other drugs, in relapsed, refractory, or newly diagnosed disease (including smoldering and symptomatic patients, and candidates and non-candidates for transplant) and in maintenance treatment (after transplant or non-transplant therapy); and for strategies to manage lenalidomide-related toxicities.

METHODS

Outcomes of interest included overall survival, event-free survival, progression-free survival, time to progression, time to next treatment, response rate, and incidence of serious toxicity. The medline, embase, and Cochrane Library databases, as well as meeting abstracts and the Web sites of relevant organizations, were systematically searched for relevant literature.

RESULTS

Recommendations were developed using the evidence from published studies and the clinical expertise of the working group and of the Cancer Care Ontario Hematology Disease Site Group.

CONCLUSIONS

Lenalidomide in combination with dexamethasone can be recommended for both previously untreated and treated patients with multiple myeloma. Guidelines for the management of cytopenias, venous thromboembolism, and second primary malignancies are discussed.

How should we treat newly diagnosed multiple myeloma patients?

Multiple myeloma (MM) is the second most frequent hematological disease. Two-thirds of newly diagnosed MM patients are more than 65 years of age. Elsewhere in this issue, McCarthy et al discuss the treatment of transplantation candidates; this chapter focuses on the data available concerning therapy for non-transplantation-eligible MM patients. Treatment goals for these non-transplantation-eligible patients should be to prolong survival by achieving the best possible response while ensuring quality of life. Until recently, treatment options were limited to alkylators, but new up-front treatment combinations based on novel agents (proteasome inhibitors and immunomodulatory drugs) plus alkylating agents have significantly improved outcomes. Other nonalkylator induction regimens are also available and provide a novel backbone that may be combined with novel second- and third-generation drugs. Phase 3 data indicate that maintenance therapy or prolonged treatment in elderly patients also improves the quality and duration of clinical responses, extending time to progression and progression-free survival; however, the optimal scheme, appropriate doses, and duration of long-term therapy have not yet been fully determined. The potential for novel treatment regimens to improve the adverse prognosis associated with high-risk cytogenetic profiles also requires further research. In summary, although we have probably doubled the survival of elderly patients, this group requires close monitoring and individualized, dose-modified regimens to improve tolerability and treatment efficacy while maintaining their quality of life.

Improving overall survival and overcoming adverse prognosis in the treatment of cytogenetically high-risk multiple myeloma

Multiple myeloma (MM) is a heterogeneous disease with certain genetic features [e.g., t(4;14), del17p] associated with worse outcome. The introduction of thalidomide, lenalidomide, and bortezomib has dramatically improved the outlook for patients with MM, but their relative benefit (or harm) for different genetic patient subgroups remains unclear. Unfortunately, the small number of patients in each subgroup frequently limits the analysis of high-risk patients enrolled in clinical trials. Strategies that result in survival of high-risk genetic subgroups approximating that of patients lacking high-risk features are said to overcome the poor prognostic impact of these high-risk features. This outcome has been difficult to achieve, and studies in this regard have so far been limited by inadequate sample size. In contrast, strategies that compare the survival of high-risk genetic subgroups randomized to different treatment arms can identify approaches that improve survival. This type of analysis is clinically useful, even if the absolute gains do not improve outcomes to levels seen in patients without high-risk cytogenetics. Reviewing available data in high-risk MM from this perspective, it appears that bortezomib has frequently been associated with improved survival, whereas thalidomide maintenance has sometimes been associated with a shorter survival.