Soft-tissue extramedullary multiple myeloma prognosis is significantly worse in comparison to bone-related extramedullary relapse

Extramedullary Multiple Myeloma: Challenges and Opportunities

Extramedullary multiple myeloma (EMM), defined in this review as soft tissue plasmacytomas resulting from hematogenous spread, is characterized by the ability of MM cells to proliferate outside of the bone marrow microenvironment. It is aggressive, often associated with high-risk cytogenetics and early relapse, and independently portends significantly shorter progression-free and overall survival, even in the era of highly effective immunotherapies. The molecular and microenvironmental factors underlying extramedullary MM dissemination continue to be studied to inform the development of better treatments. In this review, we discuss our current understanding of the biology of EMM, focusing on its distinct molecular and microenvironmental characteristics vis-à-vis MM. We also review the current treatment strategies, acknowledging the paucity of large, randomized studies specific to this population.

Extramedullary disease in multiple myeloma at diagnosis and over the course of the disease

Extramedullary disease (EMD) is an aggressive manifestation of multiple myeloma (MM) and is categorized into two distinct types: extramedullary-bone-related (EM-B) and extramedullary-extraosseous (EM-E). We aimed to investigate differences in the characteristics of disease and outcomes between these two types. This single-center, retrospective study included 132 patients with EMD who were diagnosed with MM between January 2010 and January 2020. Patients were divided into EM-B (n = 93) and EM-E (n = 39), and clinicopathological features and survival outcomes were analyzed. EMD was observed in 98 (74.2%) patients at initial diagnosis and in 34 (25.8%) during a relapse. EM-E was significantly associated with ≥ 2 involved sites, high bone marrow plasma cell percentage, high LDH and beta-2 microglobulin levels, anemia, and high-risk fluorescence in situ hybridization abnormalities compared to EM-B. Patients with EM-E had significantly shorter progression-free survival and overall survival than those with EM-B. Anemia, hypercalcemia, high LDH, EMD at relapse, ≥ 2 involved sites, and not receiving autologous stem cell transplantation were independent poor risk factors for survival. In conclusion, EMD is a heterogeneous entity, and this study demonstrated that patients with EM-E presented with different clinicopathological characteristics and had worse survival compared to those with EM-B.

Extramedullary myeloma in the era of CAR T-cell and bispecific antibody therapies

Despite the significant advancements in multiple myeloma therapy over the last decade, current unmet needs include populations of patients who continue to have inferior outcomes, such as those with high-risk cytogenetics, elderly and frail patients, plasma cell leukemia, central nervous system involvement, and extramedullary disease. Though T-cell redirecting therapies have shown excellent efficacy in advanced multiple myeloma, the ability of these therapies to overcome high-risk disease such as extramedullary involvement in myeloma is an area of critical attention. In this review, we seek to examine the specific impact of currently available data of T-cell redirecting therapies, including approved and investigational chimeric antigen receptor T-cell and bispecific antibody therapies, on outcomes in patients with extramedullary myeloma.

Talquetamab plus Teclistamab in Relapsed or Refractory Multiple Myeloma

BACKGROUND

Talquetamab (anti-G protein-coupled receptor family C group 5 member D) and teclistamab (anti-B-cell maturation antigen) are bispecific antibodies that activate T cells by targeting CD3 and that have been approved for the treatment of triple-class-exposed relapsed or refractory multiple myeloma.

METHODS

We conducted a phase 1b-2 study of talquetamab plus teclistamab in patients with relapsed or refractory multiple myeloma. In phase 1, we investigated five dose levels in a dose-escalation study. Talquetamab at a dose of 0.8 mg per kilogram of body weight plus teclistamab at a dose of 3.0 mg per kilogram every other week was selected as the recommended phase 2 regimen. The primary objective was to evaluate adverse events and dose-limiting toxic effects.

RESULTS

A total of 94 patients received treatment, with the recommended phase 2 regimen used in 44. The median follow-up was 20.3 months. Three patients had dose-limiting toxic effects (including grade 4 thrombocytopenia in 1 patient with the recommended phase 2 regimen). Across all dose levels, the most common adverse events were cytokine release syndrome, neutropenia, taste changes, and nonrash skin events. Grade 3 or 4 adverse events, most commonly hematologic events, occurred in 96% of the patients. Grade 3 or 4 infections occurred in 64% of the patients. With the recommended phase 2 regimen, a response occurred in 80% of the patients (including in 61% of those with extramedullary disease); across all dose levels, a response occurred in 78%. The likelihood of patients continuing in response at 18 months was 86% with the recommended phase 2 regimen (82% among those with extramedullary disease) and 77% across all dose levels.

CONCLUSIONS

The incidence of grade 3 or 4 infections with talquetamab plus teclistamab was higher than has been observed with either therapy alone. A response was observed in a high percentage of patients across all dose levels, with durable responses with the recommended phase 2 regimen. (Funded by Janssen Research and Development; RedirecTT-1 ClinicalTrials.gov number, NCT04586426.).

Enhancing prognosis in multiple myeloma bone disease: insights from a retrospective analysis of surgical interventions

Background

Multiple myeloma (MM) is a hematological malignancy characterized by bone marrow infiltration and osteolytic tumor formation. Despite advancements in the treatment of this disease, MM remains incurable and often leads to complications, such as multiple myeloma bone disease (MMBD). Surgical intervention is frequently necessary to manage symptoms associated with bone disease, including pain and fractures.

Methods

A retrospective review was conducted on 135 patients diagnosed with MMBD who had undergone surgery, compared to 190 patients diagnosed with MM who had not undergone surgery and served as controls. Surgical interventions were performed based on typical clinical presentations of myeloma-related bone disease, as indicated by imaging results. Patients who had only undergone percutaneous kyphoplasty or vertebroplasty (PKP/PVP) were excluded from this study.

Results

Among patients who underwent surgery, the spine was the most common site of bone metastasis, accounting for 50% of cases. The number of operations (overall survival [OS], p = 0.82; progression-free survival [PS], p = 0.41) and the order of surgery and chemotherapy treatment (OS, p = 0.85; PS, p = 0.83) did not significantly impact the outcomes. Further, MM patients with surgery exhibited a significant prognostic difference compared to those without surgery (OS, p < 0.0001). The International Staging System (ISS) stage serves as a prognostic factor for MMBD who have undergone surgery, with higher ISS stages indicating worse prognoses.

Conclusions

These results indicate that surgery and chemotherapy together improved patient survival rates compared to chemotherapy alone, thereby facilitating patients' acceptance of systemic chemotherapy. Furthermore, the appropriate timing of surgery contributes to the positive prognoses of patients with MMBD.

MYC translocation is a valuable marker for the development and relapse of extramedullary disease in multiple myeloma

OBJECTIVE

To study the cytogenetic characteristics of extramedullary disease (EMD) in patients with multiple myeloma (MM) and their impact on prognosis.

METHODS

Patients with newly diagnosed MM (NDMM) at Peking Union Medical College Hospital (Beijing, China) between June 2007 and December 2019 were recruited for this study. Demographic information, clinical data, fluorescence in situ hybridization (FISH) results of marrow and tissue samples, and survival outcome data were collected.

RESULTS

A total of 439 patients with NDMM were divided into those without EMD (non-EMD, n = 339), those with EMD with primary paraosseous plasmacytoma (pEMD-B, n = 48), those with primary EMD with soft-tissue involvement (pEMD-S, n = 33), and those with secondary EMD (sEMD, n = 19). The incidence of EMD was 18.5% (81/439) at diagnosis and 22.8% (100/439) throughout the disease course. Comparison of FISH results showed a higher proportion of RB1 deletion (n = 20; 60.0% vs. 20.0%, p = .013) and MYC translocation (n = 12; 44.4% vs. 12.5%, p = .041) in the extramedullary tissues than in the paired bone marrow samples. At diagnosis, the percentage of MYC translocations in the sEMD group was notably higher than that in the non-EMD group (55.6% vs. 15.5%, p = .012). The median overall survival (OS) of patients with pEMD-S (32 months) and sEMD (17 months) was significantly shorter (both p = .001) than that of non-EMD patients (60 months).

CONCLUSION

Soft-tissue EMD can be considered a high-risk condition, even in the era of novel agents. MYC translocation can serve as a valuable marker that correlates with extramedullary spread and relapse in patients with MM and should be considered for inclusion in routine FISH panels in clinical practice.

Daratumumab-based regimen for newly diagnosed multiple myeloma patients with paraskeletal plasmacytomas: a retrospective study in a single center

OBJECTIVE

To analyze the efficacy of daratumumab-based regimen in newly diagnosed multiple myeloma(NDMM) patients with paraskeletal plasmacytomas (PPs).

METHODS

The medical data of 28 NDMM patients with PPs were retrospectively analyzed. The daratumumab-based regimen was divided into group A, and the daratumumab-free regimen was divided into group B. The risk factors, efficacy, and overall survival (OS) were compared between the two groups.

RESULTS

The results of univariate COX regression analysis showed that only the grouping and creatinine were statistically significant. The HR value of group A was 0.30(0.10-0.88, p = 0.029), which was a protective factor for patient survival, and the HR value of creatinine was 1.00(1.00-1.01, p = 0.026), which was a risk factor for patient survival. There was a statistically significant difference in efficacy between the two groups, P = 0.025 < 0.05. The results showed that the efficacy of group A was better. There was a statistically significant difference in OS between the two groups (54:27, P = 0.002).

CONCLUSIONS

The results indicated that the treatment regimens containing daratumumab could prolong the OS of patients, suggesting that for MM patients with extramedullary disease(EMD), daratumumab-based combination treatment regimens can be given priority.

BCMA CAR-T therapy combined with pomalidomide is a safe and effective treatment for relapsed/refractory multiple myeloma

BACKGROUND

B-cell maturation antigen (BCMA)-targeted chimeric antigen receptor T-cell (CAR T-cell) therapy has exhibited remarkable efficacy in refractory or relapsed multiple myeloma (R/R MM), but recurrence and rapid progression of disease are still observed within a short time after treatment. Long-term pomalidomide therapy, which potentiates T-cell functionality, might enhance the efficacy of BCMA CAR T-cell therapy.

METHODS

We performed a single-center retrospective clinical study. Patients with relapsed or refractory multiple myeloma who received BCMA CAR T-cell infusion were enrolled in our study, and were followed by long-term pomalidomide treatment (4 mg/day) or not one month after infusion. The response and adverse events were assessed after infusion. The effect of pomalidomide on BCMA CAR T-cells was assessed in vitro.

RESULTS

The objective response rate (ORR) of BCMA-CART was 100%. Three months following CAR T-cell infusion, of the 8 patients receiving pomalidomide, except for 2 patients who stopped maintenance therapy and were lost to follow-up, all patients (6/6) achieved VGPR (very good partial response) or CR (complete response), while only 5 patients (5/8) who did not receive pomalidomide treatment achieved VGPR or better. At a median follow-up of 27 months, for the 8 patients who did not receive pomalidomide administration, the median TTP (time to progression) was 5.85 (1-14) months, while the OS (overall survival) was 10.7 (1.2-16) months. Of the 8 patients who received pomalidomide therapy after CAR T-cell infusion, the median TTP was 13 (7-13) months, while the OS was not reached. Moreover, neither long-term hematological toxicity nor drug-induced liver damage was observed during the follow-up period. Mechanistically, pomalidomide promotes antimyeloma efficacy of BCMA CAR T-cells by inhibiting cell apoptosis and enhancing cytoxicity.

CONCLUSIONS

Our results confirmed that BCMA CAR T-cell therapy combined with long-term pomalidomide had a low recurrence rate and manageable therapy-related side effects, providing a promising option for treating R/R MM.

Challenges in the treatment of soft-tissue plasmacytoma: a retrospective analysis of 120 patients with extramedullary multiple myeloma

PURPOSE

Despite the development of novel drugs and the widespread use of hematopoietic cell transplantation, the prognosis of patients (pts) with multiple myeloma and extramedullary involvement (soft-tissue plasmacytoma, STP) is rather unfavorable.

METHODS

A retrospective analysis of 120 pts with STP treated between 2007 and 2022 was performed. The effects of demographic and clinical characteristics on treatment response, progression-free survival (PFS), and overall survival (OS) were evaluated.

RESULTS

The rate of serological response to first-line STP treatment (at least partial remission) was 67%, and the rate of imaging response was 59%. With a median follow-up of 84.2 months, the median PFS was 10.5 months (primary STP: 20.2 months; secondary STP: 5.8 months), and the median OS was 24.5 months (primary STP: 34.5 months; secondary STP: 12.4 months). Based on the multivariate regression analysis, secondary STP (HRPFS 2.75; HROS 2.63) and organ involvement (HRPFS 1.45; HROS 1.68) were found to be negative prognostic factors of both PFS and OS. In a prognostic model, pts with at least one of these factors had a significantly worse PFS (HRPFS 3.31) and OS (HROS 3.45) than those with none risk factor.

CONCLUSION

In pts with STP, risk-adapted treatment strategies including immunotherapies and cell therapies are urgently required.

Liquid biopsy of peripheral blood using mass spectrometry detects primary extramedullary disease in multiple myeloma patients

Multiple myeloma (MM) is the second most prevalent hematological malignancy, characterized by infiltration of the bone marrow by malignant plasma cells. Extramedullary disease (EMD) represents a more aggressive condition involving the migration of a subclone of plasma cells to paraskeletal or extraskeletal sites. Liquid biopsies could improve and speed diagnosis, as they can better capture the disease heterogeneity while lowering patients' discomfort due to minimal invasiveness. Recent studies have confirmed alterations in the proteome across various malignancies, suggesting specific changes in protein classes. In this study, we show that MALDI-TOF mass spectrometry fingerprinting of peripheral blood can differentiate between MM and primary EMD patients. We constructed a predictive model using a supervised learning method, partial least squares-discriminant analysis (PLS-DA) and evaluated its generalization performance on a test dataset. The outcome of this analysis is a method that predicts specifically primary EMD with high sensitivity (86.4%), accuracy (78.4%), and specificity (72.4%). Given the simplicity of this approach and its minimally invasive character, this method provides rapid identification of primary EMD and could prove helpful in clinical practice.

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

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

1q21+ is associated with poor prognosis in newly diagnosed multiple myeloma patients with extramedullary disease: a retrospective study

1q21+ is a common cytogenetic abnormality in multiple myeloma (MM) and is considered an independent predictor of poor prognosis; however, its impact on extramedullary disease (EMD) remains unknown. Our study reviewed the clinical relevance and prognostic value of 1q21+ status in 92 patients with NDMM and EMD. 1q21+ was detected in 23.9% (22/92) of patients. Patients with 1q21+ presented with advanced International Staging System stages (P = 0.006), lower level of hemoglobin (P = 0.004), higher percentage of plasma cells in the bone marrow (P < 0.001), higher level of serum β2-microglobulin (7.24 g/L vs. 3.85 g/L, P = 0.003), and higher levels of lactic dehydrogenase (LDH) (206.5 U/L vs. 177 U/L, P = 0.019). The prevalence of soft tissue-related EMD (EMD-S) (54.5% vs. 18.6%, P < 0.001), renal dysfunction (50.5% vs. 17.7%, P = 0.002), and hypercalcemia (27.3% vs. 7.1%, P = 0.011) was also higher. 1q21+ was strongly associated with other high-risk cytogenetic abnormalities, including IgH/FGFR3 (22.7% vs. 4.3%, P = 0.007) and IgH/MAF translocations (22.7% vs. 1.4%, P < 0.001). 1q21+ patients had significantly shorter overall survival (OS) and progression-free survival (PFS) (OS: 24 months vs. 47 months, P = 0.002; PFS: 14 months vs. 38 months, P < 0.001); the poor survival outcomes could not be reversed by autologous hematopoietic stem cell transplantation. Multivariate analysis suggested that 1q21+ , EMD-S, elevated lactate dehydrogenase (LDH) levels, and P53 deletion were independent risk factors for poor prognosis in patients with EMD. In patients with 1q21+ EMD, hypercalcemia, elevated LDH levels, and P53 deletion were independent adverse risk prognostic factors.

Bone marrow stromal cells induce chromatin remodeling in multiple myeloma cells leading to transcriptional changes

The natural history of multiple myeloma is characterized by its localization to the bone marrow and its interaction with bone marrow stromal cells. The bone marrow stromal cells provide growth and survival signals, thereby promoting the development of drug resistance. Here, we show that the interaction between bone marrow stromal cells and myeloma cells (using human cell lines) induces chromatin remodeling of cis-regulatory elements and is associated with changes in the expression of genes involved in the cell migration and cytokine signaling. The expression of genes involved in these stromal interactions are observed in extramedullary disease in patients with myeloma and provides the rationale for survival of myeloma cells outside of the bone marrow microenvironment. Expression of these stromal interaction genes is also observed in a subset of patients with newly diagnosed myeloma and are akin to the transcriptional program of extramedullary disease. The presence of such adverse stromal interactions in newly diagnosed myeloma is associated with accelerated disease dissemination, predicts the early development of therapeutic resistance, and is of independent prognostic significance. These stromal cell induced transcriptomic and epigenomic changes both predict long-term outcomes and identify therapeutic targets in the tumor microenvironment for the development of novel therapeutic approaches.

Prognostic Implications of Circulating Plasma Cell Percentage in Multiple Myeloma and Primary Plasma Cell Leukemia Defined by New Criteria

INTRODUCTION

The definition of primary plasma cell leukemia (pPCL) has been revised from ≥20% to ≥5% circulating plasma cells (CPC). However, the precise prognosis associated with CPC remains controversial. This study aimed to investigate prognostic biomarkers for myeloma patients based on CPC presence.

METHODS

A comprehensive analysis was conducted on 309 consecutive patients diagnosed with either multiple myeloma or pPCL, utilizing peripheral blood smears stained with Wright-Giemsa.

RESULTS

Patients were grouped by CPC percentage: 0% (221, 71.5%), 1-4% (49, 15.9%), 5-19% (16, 5.2%), ≥20% (23, 7.4%). CPC >5% correlated with unfavorable characteristics, including anemia, renal dysfunction, and advanced International Staging System. Common cytogenetic abnormalities such as 1q21 amplification, 17p deletion, and Myc rearrangement were prevalent among CPC-positive patients. Median progression-free survival (PFS) and overall survival (OS) were shorter in patients with CPC ≥5% (29.47 vs. 10.03 months; 64.10 vs. 12.30 months). Additionally, PFS and OS were shorter in CPC-positive patients without autologous hematopoietic stem cell transplantation (ASCT) and those with response < partial remission to the first-line regimen. Furthermore, an association emerged between soft tissue-related extramedullary disease and inferior PFS, while Myc rearrangement correlated with abbreviated OS.

CONCLUSION

Biological characteristics displayed greater aggressiveness in patients with positive CPC, leading to significantly shorter PFS and OS. The presence of CPC, ASCT, and overall response rate were independent prognostic factors. While no new threshold for pPCL with CPCs is proposed, Myc rearrangements and CPC positivity could serve as ultra-high-risk factors for multiple myeloma.

INTRODUCTION

The definition of primary plasma cell leukemia (pPCL) has been revised from ≥20% to ≥5% circulating plasma cells (CPC). However, the precise prognosis associated with CPC remains controversial. This study aimed to investigate prognostic biomarkers for myeloma patients based on CPC presence.

METHODS

A comprehensive analysis was conducted on 309 consecutive patients diagnosed with either multiple myeloma or pPCL, utilizing peripheral blood smears stained with Wright-Giemsa.

RESULTS

Patients were grouped by CPC percentage: 0% (221, 71.5%), 1-4% (49, 15.9%), 5-19% (16, 5.2%), ≥20% (23, 7.4%). CPC >5% correlated with unfavorable characteristics, including anemia, renal dysfunction, and advanced International Staging System. Common cytogenetic abnormalities such as 1q21 amplification, 17p deletion, and Myc rearrangement were prevalent among CPC-positive patients. Median progression-free survival (PFS) and overall survival (OS) were shorter in patients with CPC ≥5% (29.47 vs. 10.03 months; 64.10 vs. 12.30 months). Additionally, PFS and OS were shorter in CPC-positive patients without autologous hematopoietic stem cell transplantation (ASCT) and those with response < partial remission to the first-line regimen. Furthermore, an association emerged between soft tissue-related extramedullary disease and inferior PFS, while Myc rearrangement correlated with abbreviated OS.

CONCLUSION

Biological characteristics displayed greater aggressiveness in patients with positive CPC, leading to significantly shorter PFS and OS. The presence of CPC, ASCT, and overall response rate were independent prognostic factors. While no new threshold for pPCL with CPCs is proposed, Myc rearrangements and CPC positivity could serve as ultra-high-risk factors for multiple myeloma.

CD38 expression by plasma cells in extramedullary multiple myeloma

Not available.

Doxorubicin-loaded PEG-CdTe QDs conjugated with anti-CXCR4 mAbs: a novel delivery system for extramedullary multiple myeloma treatment

Extramedullary multiple myeloma (EMM) is defined as the presence of plasma cells outside the bone marrow of multiple myeloma patients, and its prognosis is poor. High-dose chemotherapy with autologous stem cell transplantation, as a good option on early lines of therapy, has retained the survival benefit of youny EMM patients, but is intolerant for the majority of old patients because of drug cytotoxicity. To essentially address the intolerance above, we designed a CXCR4-PEG-CdTe-DOX (where CXCR4: chemokine receptor 4; PEG-CdTe: polyethylene glycol-modified cadmium telluride; DOX:doxorubicin) nanoplatform. First, CXCR4 is highly expressed in extramedullary plasma cells. Second, PEG-CdTe a drug carrier that controls drug release, can reduce adverse reactions, prolong drug (e.g, DOX) circulation time in the body, and form a targeting carrier after connecting antibodies. In vitro experiments showed CXCR4-PEG-CdTe-DOX facilitated intracellular drug accumulation through active CXCR4 targeting and released DOX into the microenvironment in a pH-controlled manner, enhancing the therapeutic efficacy and apoptosis rate of myeloma cells (U266). Therefore, targeted chemotherapy mediated by CXCR4-PEG-CdTe-DOX is a promising option for EMM treatment.

CDK6 protein expression is associated with disease progression and treatment resistance in multiple myeloma

Multiple myeloma (MM) is a heterogeneous malignancy of plasma cells. Despite improvement in the prognosis of MM patients after the introduction of many new drugs in the past decades, MM remains incurable since most patients become treatment-resistant. Cyclin-dependent kinase 6 (CDK6) is activated in many types of cancer and has been associated with drug resistance in MM. However, its association with disease stage, genetic alterations, and outcome has not been systematically investigated in large cohorts. Here, we analyzed CDK6 expression using immunohistochemistry in 203 formalin-fixed paraffin-embedded samples of 146 patients and four healthy individuals. We found that 61.5% of all MM specimens express CDK6 at various levels. CDK6 expression increased with the progression of disease with a median of 0% of CDK6-positive plasma cells in monoclonal gammopathy of undetermined significance (MGUS) (n = 10) to 30% in newly diagnosed MM (n = 78) and up to 70% in relapsed cases (n = 55). The highest median CDK6 was observed in extramedullary myeloma (n = 12), a highly aggressive manifestation of MM. Longitudinal analyses revealed that CDK6 is significantly increased in lenalidomide-treated patients but not in those who did not receive lenalidomide. Furthermore, we observed that patients who underwent lenalidomide-comprising induction therapy had significantly shorter progression-free survival when their samples were CDK6 positive. These data support that CDK6 protein expression is a marker for aggressive and drug-resistant disease and describes a potential drug target in MM.

Survival trends and prognostic factors of patients with newly diagnosed multiple myeloma accompanied with extramedullary disease

Background: Extramedullary disease (EMD) is an unusual event in patients with MM. This study aimed to assess the prognostic impact of EMD and develop an EMD-based risk model to estimate the survival of patients with newly diagnosed multiple myeloma (NDMM).Methods: A total of 518 patients were enrolled in this study, of which 121 presented with EMD at the initial diagnosis. Patients were divided into non-EMD, extramedullary-bone-related (EM-B) and extramedullary-extraosseous (EM-E) groups. Clinical characteristics were compared using the chi-squared test or Fisher's exact test. Survival curves were plotted using the Kaplan-Meier method, and a nomogram was constructed based on the Cox proportional hazards model.Results: Compared to patients without EMDs, patients with EM-E were younger (p = 0.028), and those with EM-B had less renal damage (p < 0.001). The EM-E group had the worst progression-free survival (PFS) and overall survival (OS). In addition, patients with multiple sites of EMD invasion or high Ki67 expression had poor OS. Lenalidomide-based treatment showed the worst outcome, and autologous stem cell transplantation (ASCT) remarkably improved the survival of patients with EMD. A prognostic model (MM prognostic index, MM-PI) comprising lactate dehydrogenase (LDH), circulating plasma cells (CPC), del(17p), and type of extramedullary involvement was developed, and a 4-factor nomogram.Conclusions: We established a risk model incorporating extramedullary disease that provides accurate and individualized survival estimates for patients with NDMM.

Difficult-to-treat patients with relapsed/refractory multiple myeloma: A review of clinical trial results

Overall outcomes for multiple myeloma have improved due to the availability of new therapies, but patients with relapsed/refractory multiple myeloma harbouring certain factors continue to pose a therapeutic challenge. These challenging features include high-risk cytogenetics, renal impairment, patient characteristics such as age and frailty, and extramedullary disease. Prior refractory status and number of prior lines add further complexity to the treatment of these patients. While newer regimens are available and have suggested efficacy in these patient populations through subgroup analyses, differences in trial definitions and cut-offs make meaningful comparisons difficult. This review aims to examine the available clinical trial data for patients with high-risk cytogenetics, renal impairment, age and frailty and extramedullary disease.

Definers and drivers of functional high-risk multiple myeloma: insights from genomic, transcriptomic, and immune profiling

Traditional prognostic models for newly diagnosed patients with multiple myeloma (MM), including International Staging System criteria and number of high-risk chromosomal abnormalities, are based on disease characteristics at diagnosis. However, the identification of patients at risk of more rapidly progressive MM is inherently a dynamic assessment. In a subset of patients with MM, adverse disease biology only becomes evident after the failure of first-line therapy. We define this entity as functional high-risk MM (FHRMM), encompassing relapse within 18 months of treatment initiation and/or within 12 months of frontline autologous stem cell transplantation. FHRMM is not adequately captured by traditional prognostic models, and there is a need for better understanding of mechanisms or risk factors for early relapse or progression. In this review, we explore potential definitions of FHRMM before delving into its underlying drivers based on genetic, transcriptomic, and immune cell profiling studies. Emerging data suggest that specific features of both myeloma cells and immune cells can enable the FHRMM phenotype. We conclude our review by discussing ongoing and future studies that seek to identify and intervene upon patients with FHRMM preemptively.

Efficacy of Bendamustine, Pomalidomide, and Dexamethasone (BPD) Regimen in Relapsed/Refractory Extramedullary Myeloma: A Retrospective Single-Centre Study, Real-Life Experience

BACKGROUND AND OBJECTIVES

Relapsed/refractory extramedullary myeloma (RREMM) is an uncommon and aggressive subtype of multiple myeloma defined by plasma cell proliferation outside the bone marrow. Therapeutic options for RREMM are limited, and the prognosis is generally unfavorable. This research aimed to assess the effectiveness of the bendamustine, pomalidomide, and dexamethasone (BPD) regimen in patients with RREMM.

MATERIAL AND METHODS

We carried out a retrospective investigation of 11 RREMM patients who underwent BPD treatment. The primary endpoint was progression-free survival. The secondary endpoints of the study were two-year survival and overall response rate (ORR). We analyzed the sociodemographic and clinical features of the patients.

RESULTS

The average age of the patients was 62 years. They had a median of four prior treatment lines, and eight patients had previously received autologous stem-cell transplantation. After eight BPD treatment cycles, the ORR stood at 54%, with one very good partial response (VGPR), five partial responses (PR), three progressive diseases (PD), and two stable diseases (SD). The median follow-up was 15 months, with a two-year PFS rate of 71.3% and a two-year survival rate of 81.8%.

CONCLUSIONS

The BPD regimen demonstrated promising effectiveness in RREMM patients, yielding favorable ORR and survival rates. To corroborate these findings and explore additional treatment alternatives for this patient group, larger prospective studies are required.

Paraskeletal plasmacytoma presenting as a chest wall mass

Extramedullary involvement in multiple myeloma is uncommon. It can present as a plasma cell mass in the soft tissue surrounding the bony structures through direct extension or in various other organs via hematogenous spread. Here, we report a case of paraskeletal plasmacytoma that manifested as a chest wall mass in a 60-year-old man.

Genetic Abnormalities in Extramedullary Multiple Myeloma

Extramedullary multiple myeloma (or extramedullary disease, EMD) is an aggressive form of multiple myeloma (MM) that occurs when malignant plasma cells become independent of the bone marrow microenvironment. This may occur alongside MM diagnosis or in later stages of relapse and confers an extremely poor prognosis. In the era of novel agents and anti-myeloma therapies, the incidence of EMD is increasing, making this a more prevalent and challenging cohort of patients. Therefore, understanding the underlying mechanisms of bone marrow escape and EMD driver events is increasingly urgent. The role of genomics in MM has been studied extensively; however, much less is known about the genetic background of EMD. Recently there has been an increased focus on driver events for the establishment of distant EMD sites. Generally, high-risk cytogenetic abnormalities and gene signatures are associated with EMD, alongside mutations in RAS signalling pathways. More recently, changes in epigenetic regulation have also been documented, specifically the hypermethylation of DNA promoter regions. Therefore, the focus of this review is to summarize and discuss what is currently known about the genetic background of EMD in MM.

Tetraplegic spinal cord injury as a presentation of multiple myeloma: A case report

Spinal cord injury is a devastating complication of cancers that exert physical compression on the spinal cord. Multiple myeloma is known predominantly as a condition that involves bony structures and can manifest with complications such as pathological fractures. However, involvement of other structures including spinal cord is a possible complication, with potentially catastrophic consequences. We describe a case of multiple myeloma presenting initially as severe paraplegia secondary to spinal cord compression in a 79-year-old man.

Daratumumab with lenalidomide and dexamethasone in relapsed or refractory multiple myeloma patients - real world evidence analysis

We performed real world evidence (RWE) analysis of daratumumab, lenalidomide and dexamethasone (Dara-Rd) versus lenalidomide and dexamethasone (Rd) treatment in relapsed/refractory multiple myeloma patients (RRMM). In total, 240 RRMM patients were treated with Dara-Rd from 2016 to 2022 outside of clinical trials in all major Czech hematology centers. As a reference, 531 RRMM patients treated with Rd were evaluated. Patients' data were recorded in the Czech Registry of Monoclonal Gammopathies (RMG). Partial response (PR) or better response (ORR) was achieved in significantly more patients in Dara-Rd than in Rd group (91.2% vs. 69.9%; p < 0.001). The median progression free survival (PFS) was 26.9 months in the Dara-Rd and 12.8 months in the Rd group (p < 0.001). Median overall survival (OS) was not reached in the Dara-Rd compared to 27.2 months in the Rd group (p = 0.023). In patients with 1-3 previous treatment lines, there was significant PFS benefit of Dara-Rd compared to Rd (median PFS not reached vs. 13.2 months; p < 0.001). In patients with > 3 previous treatment lines, there was no significant PFS benefit of Dara-Rd treatment (7.8 months vs. 9.9 months; p = 0.874), similarly in patients refractory to PI + IMIDs (11.5 months vs. 9.2 months; p = 0.376). In RWE conditions, the median PFS in RRMM patients treated with Dara-Rd is shorter when compared to clinical trials. In heavily pretreated RRMM patients, efficacy of Dara-Rd treatment is limited; best possible outcomes of Dara-Rd are achieved in minimally pretreated patients.

Management of Relapsed-Refractory Multiple Myeloma in the Era of Advanced Therapies: Evidence-Based Recommendations for Routine Clinical Practice

Multiple myeloma (MM) is the second most common hematologic malignancy in adults worldwide. Over the past few years, major therapeutic advances have improved progression-free and overall survival, as well as quality of life. Despite this recent progress, MM remains incurable in the vast majority of cases. Patients eventually relapse and become refractory to multiple drug classes, making long-term management challenging. In this review, we will focus on the treatment paradigm of relapsed/refractory MM (RRMM) in the era of advanced therapies emphasizing the available novel modalities that have recently been incorporated into routine practice, such as chimeric antigen receptor T-cell therapy, bispecific antibodies, and other promising approaches. We will also discuss major factors that influence the selection of appropriate drug combinations or cellular therapies, such as relapse characteristics, and other disease and patient related parameters. Our goal is to provide insight into the currently available and experimental therapies for RRMM in an effort to guide the therapeutic decision-making process.

Outcomes after biochemical or clinical progression in patients with multiple myeloma

Almost all patients with multiple myeloma (MM) eventually relapse, either asymptomatically or with end-organ damage. However, it remains unclear whether initiating therapy at the time of biochemical progression (BP) improves the outcomes compared with initiating therapy at the clinical progression (CP) stage. Here, we retrospectively assessed 1347 patients with relapsed MM. Most progressions were BP (60.4%); 39.6% had CP. The most prevalent symptoms at relapse were new or evolving bone disease (80.9%), anemia (38.0%), and renal failure (12.7%). Patients with BP had longer median time from second-line treatment to the next treatment compared with patients who had CP (17.0 vs 9.6 months; P < .001) as well as longer median overall survival from first relapse (59.4 vs 26.2 months; P < .001). Male sex (odds ratio [OR], 1.49; 95% confidence interval [CI], 1.02-2.18; P = .04), plasma cell labeling index ≥2% (OR, 1.58; 95% CI, 1.02-2.45; P = .04), and extramedullary disease at diagnosis (OR, 1.84; 95% CI, 1.08-3.13; P = .03) were associated with higher risk of CP, whereas very good partial remission or better had decreased risk of CP (OR, 0.62; 95% CI, 0.43-0.91; P = .02). To conclude, patients with CP have inferior postprogression outcomes compared with patients who have BP. Patients with deeper response to first-line therapy are less likely to develop CP. The presence of a specific CRAB (C, hypercalcemia; R, renal failure; A, anemia; B, bone disease) symptom at diagnosis predicts for the development of similar CRAB symptoms at relapse.

[Features of performing surgical dental operations in patients with blood tumor diseases]

OBJECTIVE

The aim of the study is the increasing the efficiency and improving the quality of dental surgical care for patients with tumor diseases of the blood system.

MATERIAL AND METHODS

For the period from 2020 to 2022 The authors examined and treated 15 patients with tumor diseases of the blood system who were hospitalized at the National Medical Research Center for Hematology of the Ministry of Health of the Russian Federation. Of these, 11 provided dental surgical benefit. There were 5 men (33%), women - 10 (67%). The mean age of the patients was 52 years. A total of 12 surgical operations were performed: biopsies - 5; opening of the infiltrate - 3; imposition of secondary sutures - 1; bougienage of the salivary gland ducts - 1, removal of the salivary gland -1 and amputation of the tooth root - 1. Four patients underwent conservative treatment.

RESULTS

The use of methods of local hemostasis made it possible to minimize the number of hemorrhagic complications. Thus, the development of external bleeding from the postoperative wound was observed in 1 (20%) (out of 5) patients in the group of acute leukemia. Hematoma was diagnosed in 2 patients. The sutures were removed on the 12th day. Finally, the wounds were epithelialized by an average of 17 days.

CONCLUSION

The authors believe that the most common surgical intervention in patients with tumorous blood diseases is a biopsy, which should be performed with partial resection of the tissue surrounding the tumor. In the course of dental interventions, hematological patients may develop complications caused by suppression of immunity and fatal bleeding.

Relapsed/Refractory Multiple Myeloma: A Review of Available Therapies and Clinical Scenarios Encountered in Myeloma Relapse

Multiple myeloma remains an incurable disease with the usual disease course requiring induction therapy, autologous stem cell transplantation for eligible patients, and long-term maintenance. Risk stratification tools and cytogenetic alterations help inform individualized therapeutic choices for patients in hopes of achieving long-term remissions with preserved quality of life. Unfortunately, relapses occur at different stages of the course of the disease owing to the biological heterogeneity of the disease. Addressing relapse can be complex and challenging as there are both therapy- and patient-related factors to consider. In this broad scoping review of available therapies in relapsed/refractory multiple myeloma (RRMM), we cover the pharmacologic mechanisms underlying active therapies such as immunomodulatory agents (IMiDs), proteasome inhibitors (PIs), monoclonal antibodies (mAbs), traditional chemotherapy, and Venetoclax. We then review the clinical data supporting the use of these therapies, organized based on drug resistance/refractoriness, and the role of autologous stem cell transplant (ASCT). Approaches to special situations during relapse such as renal impairment and extramedullary disease are also covered. Lastly, we look towards the future by briefly reviewing the clinical data supporting the use of chimeric antigen receptor (CAR-T) therapy, bispecific T cell engagers (BITE), and Cereblon E3 Ligase Modulators (CELMoDs).

A prognostication system based on clinical parameters and [18F]-FDG PET/CT in patients with newly diagnosed multiple myeloma

PURPOSE

This study aimed to assess prognosis of patients with newly diagnosed multiple myeloma (NDMM) by combining [¹⁸F]-FDG positron emission tomography (PET)/CT parameters and clinical indices.

METHODS

Clinical data and PET/CT parameters of 133 NDMM patients were retrospectively analyzed for associations between clinical indices and PET/CT parameters. Independent predictors of progression-free survival (PFS) and overall survival (OS) were determined. A new prognostic prediction system (NPPS) was constructed based on our findings. Prediction effectiveness was compared among the NPPS, International Staging System (ISS), Revised ISS (R-ISS), and R2-ISS.

RESULTS

Prevalence of elevated β2-microglobulin, serum creatinine (sCr), serum calcium (sCa), and C-reactive protein concentrations was higher in patients with higher SUVmax (≥ 5.3). Prevalence of elevated sCa, sCr, and extramedullary disease (EMD) was higher in patients with a higher number of focal lesions (≥ 10). SUVmax, serum free-light chain (sFLC) ratio, and EMD were independent predictors of PFS and OS. The NPPS used SUVmax, sFLC ratio, and EMD could effectively predict OS and was more effective at prognostication than the ISS, R-ISS, and R2-ISS.

CONCLUSIONS

[¹⁸F]-FDG PET/CT parameters play a significant role in predicting prognosis in NDMM patients. The NPPS based on SUVmax, sFLC ratio, and EMD outperformed the ISS, R-ISS, and R2-ISS in prognostication.

Analysis of High-Risk Extramedullary Relapse Factors in Newly Diagnosed MM Patients

Extramedullary relapse of multiple myeloma (MM) is often resistant to existing treatments, and has an extremely poor prognosis, but our understanding of extramedullary relapse is still limited. The incidence, clinical characteristics, impact on the prognosis of extramedullary relapse, and the risk factors for extramedullary relapse in NDMM patients were analyzed. Among the 471 NDMM patients, a total of 267 patients had disease relapse during follow-up, including 64 (24.0%) patients with extramedullary relapse. Extramedullary relapse was more common in patients with younger age, IgD subtype, elevated LDH, extensive osteolytic lesions, extramedullary involvement, and spleen enlargement at the time of MM diagnosis. Survival analysis showed that extramedullary relapse patients had significantly worse median OS than patients with relapse but without extramedullary involvement (30.8 months vs. 53.6 months, p = 0.012). Multivariate analysis confirmed that elevated LDH (OR = 2.09, p = 0.023), >2 osteolytic lesions (OR = 3.70, p < 0.001), extramedullary involvement (OR = 3.48, p < 0.001) and spleen enlargement (OR = 2.27, p = 0.011) at the time of MM diagnosis were independent risk factors for extramedullary relapse in NDMM patients. Each of the above four factors was assigned a value of 1 to form the extramedullary relapse prediction score, and the 3-year extramedullary relapse rates of patients in the 0−2 and 3−4 score groups were 9.0 % and 76.7 %, respectively. This study suggested that extramedullary relapse was associated with poor clinical characteristics and poor prognosis in NDMM patients. The extramedullary relapse prediction score model composed of LDH, osteolytic lesions, extramedullary involvement and spleen enlargement has a better ability to predict extramedullary relapse than the existing ISS and R-ISS stages.

A prognostic model for patients with primary extramedullary multiple myeloma

Background: Extramedullary disease is a manifestation of multiple myeloma, the prognosis of which remains poor even in the era of novel drugs. Therefore, we aimed to develop a predictive model for patients with primary extramedullary multiple myeloma (EMM). Methods: Clinical and laboratory data of patients diagnosed with primary EMM between July 2007 and July 2021 were collected and analyzed. Univariate and least absolute shrinkage and selection operation Cox regression analyses (LASSO) were used to select prognostic factors for overall survival (OS) to establish a nomogram prognostic model. The performance of the model was evaluated using concordance index which was internally validated by bootstraps with 1,000 resample, area under the curve (AUCs), and calibration curves. Results: 217 patients were included in this retrospective study. Patients with EMM had a higher rate of belonging to the male sex, age >50 years, advanced Durie-Salmon stage III, hypercalcemia, and low hemoglobin level. Compared with patients with bone-related extramedullary disease, those with extraosseous-related extramedullary disease had a higher frequency of advanced Durie-Salmon stage III, lower rate of hypercalcemia, and elevated prothrombin time. The OS and progression-free survival (PFS) of patients with bone-related extramedullary disease were significantly higher than those of patients with extraosseous-related extramedullary disease. After the univariate and LASSO analyses, six prognostic factors, including performance status, number of extramedullary involved sites, β2-microglobulin, lactate dehydrogenase, monocyte-lymphocyte ratio, and prothrombin time, were integrated to establish a nomogram. The model showed robust discrimination with a concordance index (C-index) of 0.775 (95% confidence interval [CI], 0.713-0.836), internally validated with the corrected C-index of 0.756, and excellent performance in time-dependent AUCs compared with other staging systems. The AUCs for 1-, 3-, and 5-year OS were 0.814, 0.744, and 0.832, respectively. The calibration curves exhibited good consistency between the observed and nomogram-predicted OS. The 5-year OS of patients in the high-risk group (23.3%; 95% CI, 13.9%-39.3%) was much worse than that in the low-risk group (73.0%; 95% CI, 62.5%-85.4%; p < 0.001). Conclusion: The nomogram predictive model based on six clinical variables showed good prognostic performance and could better predict individual survival in patients with EMM.

Involvement of Small Non-Coding RNA and Cell Antigens in Pathogenesis of Extramedullary Multiple Myeloma

Extramedullary multiple myeloma (EMD) is an aggressive disease; malignant plasma cells lose their dependence in the bone marrow microenvironment and migrate into tissues. EMD is a negative prognostic factor of survival. Using flow cytometry and next-generation sequencing, we aimed to identify antigens and microRNAs (miRNAs) involved in EMD pathogenesis. Flow cytometry analysis revealed significant differences in the level of clonal plasma cells between MM and EMD patients, while the expression of CD markers was comparable between these two groups. Further, miR-26a-5p and miR-30e-5p were found to be significantly down-regulated in EMD compared to MM. Based on the expression of miR-26a-5p, we were able to distinguish these two groups of patients with high sensitivity and specificity. In addition, the involvement of deregulated miRNAs in cell cycle regulation, ubiquitin-mediated proteolysis and signaling pathways associated with infections or neurological disorders was observed using GO and KEGG pathways enrichment analysis. Subsequently, a correlation between the expression of analyzed miRNAs and the levels of CD molecules was observed. Finally, clinicopathological characteristics as well as CD antigens associated with the prognosis of MM and EMD patients were identified. Altogether, we identified several molecules possibly involved in the transformation of MM into EMD.

Clinical Characteristics and Prognosis of Multiple Myeloma With Myelomatous Pleural Effusion: A Retrospective Single-Center Study

Objectives: Myelomatous pleural effusion is a rare presentation of extramedullary disease in multiple myeloma, which has been reported with dismal prognosis. We aimed to explore whether it has distinctive clinical characteristics and outcomes compared to other anatomic locations of extramedullary involvements. Methods: Multiple myeloma patients diagnosed at our institution from 2010 to 2020 were retrieved retrospectively. In total, 42 pairs of patients with and without extramedullary disease were enrolled, including 13 with myelomatous pleural effusion. The clinical and laboratory parameters were collected and compared between different groups. Prognostic effect of myelomatous pleural effusion was assessed in cox regression model and Kaplan-Meier curves. Results: Myelomatous pleural effusion patients presented a higher level of β2-microglobulin (P = .041), greater prevalence of multisites extramedullary lesions (69.2% vs 38.0%, P = .036) and International Staging System stage III (76.9% vs 44.8%, P = .016). Median overall survival was 60.6 months in patients without extramedullary disease versus 35.0 months in patients with extramedullary disease (P = .045). Notably, median overall survival was 13.0 months in myelomatous pleural effusion patients versus 37.0 months in other extramedullary disease patients with a significant difference (P = .029). Furtherly, multivariate analysis recognized myelomatous pleural effusion as an independent prognostic indicator (Hazard ratio: 2.669, 95% CI [1.132-6.293], P = .025). Conclusion: Myelomatous pleural effusion patients presented heavier tumor burden and worse outcomes than other extramedullary diseases.

Unexpected Heterogeneity of Newly Diagnosed Multiple Myeloma Patients with Plasmacytomas

In multiple myeloma (MM), malignant plasma cells infiltrate the bone marrow. In some cases, plasma cells migrate out of the bone marrow creating either para-skeletal plasmacytomas (PS) or infiltrating soft tissues as extramedullary plasmacytomas (EMD). The aim of this study was to define risk groups in newly diagnosed MM (NDMM) patients with PS and EMD plasmacytomas. In total, 523 NDMM patients with PS plasmacytomas and 196 NDMM patients with EMD plasmacytomas were diagnosed in the Czech Republic between 2004 and 2021 using modern imaging methods. Patients’ data were analyzed from the Registry of Monoclonal Gammopathies of the Czech Myeloma Group. In NDMM patients with PS plasmacytomas, we found a subgroup with <5% of bone-marrow plasma cells to have the best prognosis (mPFS: 58.3 months (95% CI: 33.0−NA); mOS: not reached). The subgroup with >5% of bone-marrow plasma cells and ≥3 plasmacytomas had the worst prognosis (mPFS: 19.3 months (95% CI: 13.4−28.8), p < 0.001; mOS: 27.9 months (95% CI: 19.3−67.8), p < 0.001). Our results show association between tumor burden and prognosis of NDMM patients with plasmacytomas. In the case of PS plasmacytomas, NDMM patients with low BM PC infiltration have an excellent prognosis.

Paraskeletal and extramedullary plasmacytomas in multiple myeloma at diagnosis and at first relapse: 50-years of experience from an academic institution

From January 1970 to December 2018, 1304 patients were diagnosed with multiple myeloma (MM) at our institution and 256 (19.6%) had plasmacytomas (Ps) (paraskeletal –PPs- 17.6%, extramedullary –EMPs-1.9%). Patients with Ps had lower serum M-protein and less advanced ISS stage than those without. At first relapse, 192 out of 967 patients (19.8%) developed Ps (PPs 14.6%, EMPs 5.1%). The only factor associated with Ps at relapse was the presence of Ps at diagnosis (46% vs 13%, p < 0.00001) with no impact with exposure to novel drugs or previous autologous stem-cell transplantation (ASCT). The median overall survival (OS) was 45, 44 and 20 months for patients without Ps, PPs and EMPs, respectively (p = 0.013). Patients with PPs who underwent ASCT had similar OS than those without Ps (98 vs. 113 months) and significantly longer than those with EMPs (98 vs 47 months, p = 0.006). In patients non-eligible for ASCT the presence of PPs or EMPs was associated with shorter OS compared with patients without Ps (32 vs. 24 vs. 6 months, p = 0.009). In the relapsed setting, a significant survival benefit was observed beyond the year 2000, but still with significant differences among patients without Ps, PPs and EMPs (37 vs 22 vs 16 months, p = 0.003). Importantly, rescue therapy with combinations of proteasome-inhibitors plus immunomodulatory drugs was associated with prolonged OS from first relapse (over 6 years), even in patients with EMPs.

Evaluation of isatuximab in patients with soft-tissue plasmacytomas: An analysis from ICARIA-MM and IKEMA

The Phase 3 ICARIA-MM (NCT02990338) and IKEMA (NCT03275285) studies demonstrated that isatuximab (Isa) plus pomalidomide (P) and dexamethasone (d; Isa-Pd) or carfilzomib (K) and d (Isa-Kd) improved progression-free survival (PFS) versus Pd or Kd in patients with relapsed and/or refractory multiple myeloma. In this post hoc analysis of patients with soft-tissue plasmacytomas, we evaluated Isa-Pd/Isa-Kd efficacy using central radiology and central laboratory assessments. Given the low incidence of soft-tissue plasmacytomas (7.8 %, ICARIA-MM; 6.3 %, IKEMA), efficacy data were pooled across the two studies. PFS (HR, 0.47; 95 % CI, 0.21-1.08), overall response rate (50.0 % vs 17.7 %), and very good partial response or better rate (26.9 % vs 11.8 %) were improved with Isa-Pd/Isa-Kd versus Pd/Kd, with consistent improvements within individual studies. Patients with soft-tissue plasmacytomas who received Isa-Pd/Isa-Kd had similar median PFS compared with those without soft-tissue plasmacytomas and received Pd/Kd. Safety is reported individually per study. Longer median treatment duration and more Grade ≥ 3 treatment-emergent adverse events occurred in the Isa versus control arms in ICARIA-MM (36.9 vs 8.4 weeks; 85.7 % vs 70.0 %) and IKEMA (41.9 vs 29.9 weeks; 100.0 % vs 57.1 %); however, Isa did not increase the percentage of patients with fatal events or drug discontinuation. Isa-Pd or Isa-Kd is a potential new treatment option and partially overcomes the poor prognosis associated with soft-tissue plasmacytomas in relapsed and/or refractory multiple myeloma.

Testicular Plasmacytoma Masking as Epididymo-orchitis in a Known Multiple Myeloma Patient

BACKGROUND/AIM

Extramedullary plasmacytoma (EMP) is defined as a localized plasma cell neoplasm that arises in tissues other than the bone. The most common sites of involvement of EMP are the upper airways followed by lymph nodes, gastrointestinal tract, thyroid gland, skin, brain, liver, and lungs. Testicular plasmacytoma has a very rare occurrence with about 70 cases reported in literature to date.

CASE REPORT

We describe a 52-year-old-male with a diagnosis of multiple myeloma presenting with lytic lesions of the axial skeleton. He had lambda light chain restricted, R-ISS stage II with high risk cytogenetics as he tested positive for t(4;14). He underwent four cycles of cyclophosphamide, bortezomib and dexamethasone followed by auto-peripheral stem cell transplantation. He was kept on ixazomib, lenalidomide and dexamethasone maintenance therapy, but relapsed soon after and was diagnosed with plasmacytoma of the left lung. Therapy was switched to daratumumab, carfilzomib and dexamethasone and the patient received radiation of his left lung. He then developed left painless testicular mass which was treated with six weeks course of antibiotics. However due to persistence of concerning features on scrotal ultrasound post-treatment, the patient underwent radical orchiectomy with pathology coming back positive for plasma cells.

CONCLUSION

The testes serve as a sanctuary site for hematological malignancies due to the presence of the testicular-blood barrier. Hence, it is imperative to keep a high index of suspicion for testicular plasmacytoma in the right clinical context when evaluating a patient with known multiple myeloma.

Minimal residual disease detection by next-generation sequencing in multiple myeloma: Promise and challenges for response-adapted therapy

Assessment of minimal residual disease (MRD) is becoming a standard diagnostic tool for curable hematological malignancies such as chronic and acute myeloid leukemia. Multiple myeloma (MM) remains an incurable disease, as a major portion of patients even in complete response eventually relapse, suggesting that residual disease remains. Over the past decade, the treatment landscape of MM has radically changed with the introduction of new effective drugs and the availability of immunotherapy, including targeted antibodies and adoptive cell therapy. Therefore, conventional serological and morphological techniques have become suboptimal for the evaluation of depth of response. Recently, the International Myeloma Working Group (IMWG) introduced the definition of MRD negativity as the absence of clonal Plasma cells (PC) with a minimum sensitivity of <10⁻⁵ either by next-generation sequencing (NGS) using the LymphoSIGHT platform (Sequenta/Adaptative) or by next-generation flow cytometry (NGF) using EuroFlow approaches as the reference methods. While the definition of the LymphoSIGHT platform (Sequenta/Adaptive) as the standard method derives from its large use and validation in clinical studies on the prognostic value of NGS-based MRD, other commercially available options exist. Recently, the LymphoTrack assay has been evaluated in MM, demonstrating a sensitivity level of 10⁻⁵, hence qualifying as an alternative effective tool for MRD monitoring in MM. Here, we will review state-of-the-art methods for MRD assessment by NGS. We will summarize how MRD testing supports clinical trials as a useful tool in dynamic risk-adapted therapy. Finally, we will also discuss future promise and challenges of NGS-based MRD determination for clinical decision-making. In addition, we will present our real-life single-center experience with the commercially available NGS strategy LymphoTrack-MiSeq. Even with the limitation of a limited number of patients, our results confirm the LymphoTrack-MiSeq platform as a cost-effective, readily available, and standardized workflow with a sensitivity of 10⁻⁵. Our real-life data also confirm that achieving MRD negativity is an important prognostic factor in MM.

EMD originates from hyaluronan-induced homophilic interactions of CD44 variant-expressing MM cells under shear stress

Extramedullary disease (EMD) is known to be associated with chemoresistance and poor prognosis in multiple myeloma (MM); however, the mechanisms of its development are not fully understood. Elucidating the mechanism of EMD development and its therapeutic targeting would greatly contribute to further improvement of treatment outcome in patients with MM. Here, we show that bone marrow stroma cell-derived hyaluronan (HA) elicits homophilic interactions of MM cells by binding to surface CD44, especially long-stretch variants, under physiological shear stress and generates cell clusters that might develop into EMD. We recapitulated the development of EMD via administration of HA in a syngeneic murine MM model in a CD44-dependent manner. HA-induced MM cell clusters exhibited the specific resistance to proteasome inhibitors (PIs) in vitro and in murine models via γ-secretase-mediated cleavage of the intracellular domains of CD44, which in turn transactivated PI resistance-inducible genes. Treatment of HA-injected mice with anti-CD44 antibody or γ-secretase inhibitors readily suppressed the development of EMD from transplanted MM cells and significantly prolonged the survival of recipients by overcoming PI resistance. The HA-CD44 axis represents a novel pathway to trigger EMD development and could be a target of the prediction, prevention, and treatment of EMD in patients with MM.

Advances in the treatment of extramedullary disease in multiple myeloma

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Extramedullary multiple myeloma results in an adverse prognosis.

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Novel agents such as bortezomib, lenalidomide, pomalidomide, isatuximab and selinexor showed efficacy and were recommended to treat EMD.

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For EMD at special sites, marizomib has advantages in the treatment of CNS-MM; Daratumumab combining with intrapleural bortezomib administration is active in treating myelomatous pleural effusion.

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Based on treatment experience of EMD in our department, we summarized treatment approach for EMD.

Extramedullary disease (EMD) is characterized by plasma cells outside of bone marrow in multiple myeloma (MM) patients, which results in an adverse prognosis. The cornerstone of treatment consists of combination therapy including proteasome inhibitors, immunomodulatory agents, steroids, followed by consolidative autologous hematopoietic stem cell transplantation in eligible patients. This review summarized the recent advances in the treatment of EMD. Bortezomib based therapy showed efficacy and was recommended to treat EMD. Marizomib had advantages in the treatment of central nervous system-multiple myeloma (CNS-MM) because of its good central nervous system penetrability. Immunomodulatory drugs such as lenalidomide and pomalidomide have been reported to be effective. Isatuximab and selinexor were also active. Based on the treatment experience of EMD in our department, we summarized treatment approach for EMD. However, the benefits of patients with EMD from the new era of novel drugs were limited. Novel drugs combination, monoclonal antibody, molecular targeted therapy, cellular immunotherapy and autologous stem cell transplantation (ASCT) are under investigation. Therapeutic studies and clinical trials specifically target EMD should be conducted. Hopefully, these treatment options for EMD will be demonstrated efficacy in the future.

Central Nervous System Myeloma and Unusual Extramedullary Localizations: Real Life Practical Guidance

Central nervous system localization of multiple myeloma (CNS-MM) accounts for about 1% of all MM during disease course or even rarer at diagnosis. A difference in the origin, i.e., osteodural or primary dural vs leptomeningeal/intraparenchymal, seems to define two distinct types of intracranial myeloma, with different clinical behavior. CNS-MM may occur also as a presentation of MM. Treatment is still unsatisfactory and many treatments have been reported: chemotherapy, intrathecal therapy, and radiotherapy, with dismal prognosis. Other sites of myeloma localization could be also of interest and deserve description. Because of the rarity and aggressiveness of the disease clinicians are often doubtful on how to treat it since there is no general agreement. Moreover, recent drugs such as the anti CD38 monoclonal antibody, immunomodulatory drugs, and proteasome inhibitors have changed the treatment of patients with MM with a significant improvement in overall response and survival. The role of novel agents in CNS MM management and unusual presentations will be discussed as well as the potential role of other new immunomodulatory drugs and proteasome inhibitors that seem to cross the blood-brain barrier. The purpose of this review is to increase awareness of the clinical unusual presentation and neuroradiological findings, give practical diagnostic advice and treatment options algorithm.

High-risk disease in newly diagnosed multiple myeloma: beyond the R-ISS and IMWG definitions

Multiple myeloma (MM) is an acquired malignant plasma cell disorder that develops late in life. Although progression free and overall survival has improved across all age, race, and ethnic groups, a subset of patients have suboptimal outcomes and are labeled as having high risk disease. A uniform approach to risk in NDMM remains elusive despite several validated risk stratification systems in clinical use. While we attempt to capture risk at diagnosis, the reality is that many important prognostic characteristics remain ill-defined as some patients relapse early who were defined as low risk based on their genomic profile at diagnosis. It is critical to establish a definition of high risk disease in order to move towards risk-adapted treatment approaches. Defining risk at diagnosis is important to both effectively design future clinical trials and guide which clinical data is needed in routine practice. The goal of this review paper is to summarize and compare the various established risk stratification systems, go beyond the R-ISS and international myeloma working group risk stratifications to evaluate specific molecular and cytogenetic abnormalities and how they impact prognosis independently. In addition, we explore the wealth of new genomic information from recent whole genome/exome sequencing as well as gene expression data and review known clinical factors affecting outcome such as disease burden and early relapse as well as patient related factors such as race. Finally, we provide an outlook on developing a new high risk model system and how we might make sense of co-occurrences, oncogenic dependencies, and mutually exclusive mutations.

Relapse with plasmacytoma after upfront autologous stem cell transplantation in multiple myeloma

Please present P values consistently.Plasmacytoma has been reported to be associated with a poor prognosis in patients with multiple myeloma (MM). In this study, we evaluated the incidence of relapse with plasmacytoma and survival outcomes after upfront autologous stem cell transplantation (ASCT). This study retrospectively analyzed the data of 303 patients with MM who underwent upfront ASCT between April 2000 and April 2018 at eight institutes in the Republic of Korea. In total, 52 patients (17.1%) had plasmacytoma at MM relapse after upfront ASCT, of whom, 27 had paramedullary plasmacytoma (PMD) and 25 had extramedullary plasmacytoma (EMD). Patients with initial plasmacytoma were more likely to have plasmacytoma at MM relapse than those without initial plasmacytoma (37.1% vs. 11.2%). Over a median follow-up of 66.0 months, patients with plasmacytoma at relapse had significantly inferior overall survival (OS) than those without plasmacytoma (43.9 vs. 100.7 months, P < 0.001), but the OS did not significantly differ between patients with EMD and those with PMD (42.2 vs. 56.6 months, P=0.464). After MM relapse, all patients received salvage therapy, and progression-free survival after relapse was significantly shorter in patients with plasmacytoma than in those without (6.4 vs. 12.4 months, P = 0.007). This study showed that plasmacytoma frequently developed at MM relapse after upfront ASCT in patients with plasmacytoma at the time of diagnosis. Plasmacytoma at relapse was significantly associated with a poor prognosis.

Comparison of clinical features of multiple myeloma with paraosseous and extraosseous plasmacytoma in the era of novel drugs: a systemic review and meta-analysis

BACKGROUND

Extramedullary myeloma constitutes a small portion of multiple myeloma (MM) with a more aggressive clinical course and inferior prognosis. Two types of extramedullary myeloma, paraosseous (PO) and extraosseous (EO) plasmacytoma, differ significantly in pathogenesis, clinical features and outcomes but there have been limited studies comparing them based on large patient cohorts.

METHODS

Relevant studies published before June 2021 were searched in MEDLINE, Embase and Cochrane databases. Two reviewers independently assessed the quality of included studies and discrepancies were evaluated by a third reviewer. Extracted data was analyzed by Stata12.

RESULTS

997 MM patients with PO and 288 with EO plasmacytoma were analyzed. Patients with EO plasmacytoma tended to have larger tumor burden according to International Staging System though it did not reach statistical significance (P=0.1). Newly diagnosed MM (NDMM) patients with EO plasmacytoma had significantly inferior outcome than PO plasmacytoma (OS OR=2.32, 95% CI 1.80-2.98, P<0.001, I²=40.9%; PFS OR=1.66, 95% CI 1.39-1.99, P<0.001, I²=0.0%). No significant difference in OS was found in relapsed MM patients. Auto-HSCT seemed to attenuate the disadvantage in response rate of EO plasmacytoma.

CONCLUSIONS

NDMM patients with EO plasmacytoma had significantly inferior prognosis than PO plasmacytoma, while relapsed MM patients did not show such difference. More strategies are needed to improve its clinical outcome.

Extramedullary disease in multiple myeloma: a systematic literature review

Extramedullary involvement (or extramedullary disease, EMD) represents an aggressive form of multiple myeloma (MM), characterized by the ability of a clone and/or subclone to thrive and grow independent of the bone marrow microenvironment. Several different definitions of EMD have been used in the published literature. We advocate that true EMD is restricted to soft-tissue plasmacytomas that arise due to hematogenous spread and have no contact with bony structures. Typical sites of EMD vary according to the phase of MM. At diagnosis, EMD is typically found in skin and soft tissues; at relapse, typical sites involved include liver, kidneys, lymph nodes, central nervous system (CNS), breast, pleura, and pericardium. The reported incidence of EMD varies considerably, and differences in diagnostic approach between studies are likely to contribute to this variability. In patients with newly diagnosed MM, the reported incidence ranges from 0.5% to 4.8%, while in relapsed/refractory MM the reported incidence is 3.4 to 14%. Available data demonstrate that the prognosis is poor, and considerably worse than for MM without soft-tissue plasmacytomas. Among patients with plasmacytomas, those with EMD have poorer outcomes than those with paraskeletal involvement. CNS involvement is rare, but prognosis is even more dismal than for EMD in other locations, particularly if there is leptomeningeal involvement. Available data on treatment outcomes for EMD are derived almost entirely from retrospective studies. Some agents and combinations have shown a degree of efficacy but, as would be expected, this is less than in MM patients with no extramedullary involvement. The paucity of prospective studies makes it difficult to justify strong recommendations for any treatment approach. Prospective data from patients with clearly defined EMD are important for the optimal evaluation of treatment outcomes.