Extramedullary multiple myeloma

Multiple myeloma with extramedullary plasmacytoma: pathogenesis and clinical case

Background. Multiple myeloma complicated by extramedullary plasmacytoma is an unfavorable variant of the disease. It remains unknown what triggers tumor transformation. The review presents literature data on the pathogenesis of extramedullary disease, as well as a clinical example of a comprehensive study of the tumor substrate.

Aim. To study the molecular and biological characteristics of the tumor substrate of the bone marrow and extramedullary plasmacytoma using various research methods.

Materials and methods. A 55-year-old patient was admitted to National Medical Research Center for Hematology with a diagnosis of multiple myeloma occurring with extramedullary plasmacytoma of the retroperitoneal space. dNA was isolated from samples of different localization (blood plasma, Cd138+ bone marrow cells, plasmacytoma and buccal epithelial cells). The profile of short tandem dNA repeats (STR) from the obtained samples was studied by multiplex polymerase chain reaction followed by fragment analysis. fluorescent in situ hybridization (fISH) of bone marrow Cd138+ cells was performed using various dNA probes. Comparative genomic hybridization on a microarray (arrayCGH) plasmacytoma dNA was also performed. The mutation profile of the KRAS, NRAS, BRAF genes was studied by Sanger sequencing in tumor samples of various localizations.

Results. The induction therapy (vCd (bortezomib + cyclophosphamide + dexamethasone), vRd (bortezomib + lenalidomide + dexamethasone), daratumumab therapy) was ineffective, death occurred 4 months after the first clinical manifestations appeared. Comparison of STR markers of circulating cell-free tumor dNA (cfdNA), Cd138+ bone marrow cells, and plasmacytoma revealed the largest number of involved loci exactly in plasmacytoma’ dNA. A mutation in the NRAS gene was found only in plasmacytoma’ dNA. This indicates the presence of another clone of tumor cells in the extra-medullary plasmacytoma. Molecular karyotyping of plasmacytoma using the arrayCGH method revealed rearrangements of many chromosomes. 1p32.3 bi-allelic deletion, amplification of 1q21, 8q24/MyC rearrangements and del17p13 were confirmed by arrayCGH molecular karyotyping and fISH studies in bone marrow and plasmacytoma.

Conclusion. A comprehensive molecular genetic study of the extramedullary plasmacytoma’ substrate is necessary to understand the pathogenesis mechanisms and, on this basis, to develop differentiated therapeutic approaches.

Reduced CXCR4 expression in associated with extramedullary and predicts poor survival in newly diagnosed multiple myeloma

BACKGROUND

Multiple myeloma (MM), a bone marrow-resident hematological malignancy of plasma cells, has remained largely incurable despite the recent advancement in novel therapies. The heterogeneity of myeloma cells makes risk stratification of MM important for therapeutic regimen planning.

RESEARCH DESIGN AND METHODS

No immunohistochemical (IHC) predictive and prognostic marker of MM has been constructed yet. Herein, the prognostic value of chemokine (C-X-C motif) receptor 4 (CXCR4) expression in 48 newly diagnosed MM patients was explored using IHC. Correlations between CXCR4 expression and clinical features of MM were analyzed.

RESULTS

CXCR4-positive patients significantly outperformed CXCR4-negative patients in both 3-year estimated overall survival (93.8% vs 45.8%, P = 0.0392) and progression-free survival (57.1% vs 40.9%, P = 0.0436).

CONCLUSIONS

The incidence of extramedullary lesions in CXCR4-negative patients increased significantly compared with CXCR4-positive patients. Plasma cells that reduce CXCR4 expression have poor prognosis and increase the incidence of extramedullary lesions.

Pathways of Angiogenic and Inflammatory Cytokines in Multiple Myeloma: Role in Plasma Cell Clonal Expansion and Drug Resistance

Multiple myeloma (MM) is the second most common hematological malignancy, and despite the introduction of innovative therapies, remains an incurable disease. Identifying early and minimally or non-invasive biomarkers for predicting clinical outcomes and therapeutic responses is an active field of investigation. Malignant plasma cells (PCs) reside in the bone marrow (BM) microenvironment (BMME) which comprises cells (e.g., tumour, immune, stromal cells), components of the extracellular matrix (ECM) and vesicular and non-vesicular (soluble) molecules, all factors that support PCs’ survival and proliferation. The interaction between PCs and BM stromal cells (BMSCs), a hallmark of MM progression, is based not only on intercellular interactions but also on autocrine and paracrine circuits mediated by soluble or vesicular components. In fact, PCs and BMSCs secrete various cytokines, including angiogenic cytokines, essential for the formation of specialized niches called “osteoblastic and vascular niches”, thus supporting neovascularization and bone disease, vital processes that modulate the pathophysiological PCs–BMME interactions, and ultimately promoting disease progression. Here, we aim to discuss the roles of cytokines and growth factors in pathogenetic pathways in MM and as prognostic and predictive biomarkers. We also discuss the potential of targeted drugs that simultaneously block PCs’ proliferation and survival, PCs–BMSCs interactions and BMSCs activity, which may represent the future goal of MM therapy.

Phase II trial of daratumumab with DCEP in relapsed/refractory multiple myeloma patients with extramedullary disease

Extramedullary multiple myeloma (EMD) is an aggressive subentity of multiple myeloma (MM) with poor prognosis. As more innovative therapeutic approaches are needed for the treatment of MM with EMD, we conducted this multicenter, non-randomized phase II trial of daratumumab in combination with dexamethasone, cyclophosphamide, etoposide and cisplatin (DARA-DCEP). A total of 32 patients (median age 59, range 35–73) were treated with DARA-DCEP. Based on the best response during the study, the complete remission (CR) rate was 35.5% and overall response rate (ORR) 67.7%. During the median follow-up of 11 months, the median progression-free survival (PFS) was 5 months and median overall survival (OS) 10 months. There were 7 long-term responders whose median PFS was not reached. The most common grade ≥ 3 hematologic AE was thrombocytopenia. The most common non-hematologic AE was nausea (22.6%), followed by dyspepsia, diarrhea and stomatitis (all 12.9%). Grade ≥ 3 daratumumab infusion-related reaction was noted in 9.7% of the patients. Except for the planned 30% dose adjustment in cycle 1, only 2 patients required DCEP dose reduction. This is one of the very few prospective trials focusing on EMD and we successfully laid grounds for implementing immunochemotherapy in MM treatment.

This is one of the very few prospective trials focusing on refractory multiple myeloma with extramdedullary disease (EMD).

We successfully laid grounds for implementing immunochemotherapy in EMD treatment.

Extramedullary Multiple Myeloma: A Patient-Focused Review of the Pathogenesis of Bone Marrow Escape

Multiple myeloma (MM) is a neoplastic clonal proliferation of plasma cells, predominantly in the bone marrow. The presentation of MM in extramedullary tissue, particularly the liver, is uncommon with only a few reported cases in literature. We report a rare and unusual presentation of kappa light chain restricted MM with progression of disease to involve the liver. MM was initially diagnosed on bone marrow biopsy, initially treated with carfilzomib, lenalidomide and dexamethasone, later changed to bortezomib, daratumumab and dexamethasone. There was subsequent progression with a new biopsy-proven myelomatous liver lesion. The patient could not receive high-dose chemotherapy due to multiple co-morbidities and extent of disease and eventually succumbed to her disease rapidly. This article emphasizes the poor prognosis of extramedullary involvement in MM and the pathogenic mechanisms by which it develops. Based on a review of the literature of other cases and case series of solitary or diffuse myeloma involvement in the liver, high-dose chemotherapy in combination with proteasome inhibitors and immunomodulators has the best success rate with less relapse and progressive disease in extramedullary myeloma. Our analysis concluded that the gain of CD44, loss of CD56, loss of very late antigen-4 (VLA-4), imbalance of the chemokine receptor-4-chemokine ligand-12 (CXCR4-CXCL12) axis, metastasis-associated lung adenocarcinoma 1 (MALAT1) upregulation, RAS pathway activation as well as 13q and 17p deletions show an increased propensity of malignant plasma cells to leave the bone marrow and hone in extramedullary sites giving rise to more aggressive extramedullary diseases. Targeted therapeutics such as CD44v-directed therapy and reactivation of p53 to wild-type conformation could potentially be evaluated as treatment options in the future to improve outcomes in this aggressive form of MM, especially in patients with advanced disease and limited treatment options.

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.

Phase 1 study of C-CAR088, a novel humanized anti-BCMA CAR T-cell therapy in relapsed/refractory multiple myeloma

Background

Anti-B-cell maturation antigen (BCMA) chimeric antigen receptor T-cell (CAR T) therapy showed remarkable efficacy in patients with relapsed or refractory multiple myeloma (RRMM). This phase 1 dose-escalation and expansion study developed C-CAR088, a novel second-generation humanized anti-BCMA CAR T-cell therapy, and assessed the safety and efficacy of three dosages of C-CAR088 in patients with RRMM.

Methods

Patients received lymphodepletion with three doses of cyclophosphamide (300 mg/m²) and three doses of fludarabine (30 mg/m²) on days –5, –4, and –3, followed by an infusion of C-CAR088 on day 0. Doses of 1.0×10⁶, 3.0×10⁶, and 6.0×10⁶ CAR T cells/kg (±20%) were tested in the dose-escalation cohorts and expansion cohorts. The primary endpoint was treatment safety, including the rate of treatment-emergent adverse events after cell infusion. Secondary endpoints were the overall response rate and progression-free survival. The exploratory endpoints were the quantification of C-CAR088 CAR T cells, selection of cytokines and chemokines in blood, and measurement of tumor BCMA expression.

Results

As of July 2, 2021, 31 patients had been infused with C-CAR088. Any grade cytokine release syndrome (CRS) occurred in 29 patients (93.5%), and grade 3 CRS occurred in 3 patients (9.7%). One patient from the high-dose group (4.5–6.0×10⁶ CAR T cells/kg) developed grade 1 neurotoxicity. No dose-limiting toxicities were observed in any dose group, and all adverse events were reversible after proper management. The overall response, stringent complete response, complete response (CR), and very good partial response rates were 96.4%, 46.4%, 10.7%, and 32.1%, respectively. The CR rate in the medium-dose (3.0×10⁶ CAR T cells/kg) and high-dose (4.5–6.0×10⁶ CAR T cells/kg) groups was 54.5% and 71.4%, respectively. In the CR group, 15 (93.7%) patients achieved minimal residual disease (MRD) negativity (test sensitivity >1/10⁻⁵). All seven patients with double-hit or triple-hit multiple myeloma achieved MRD-negative CR.

Conclusions

The present study demonstrated that C-CAR088 had a good safety profile and high antitumor activity in patients with RRMM, constituting a promising treatment option for RRMM.

Trial registration number

NCT03815383, NCT03751293, NCT04295018, and NCT04322292.

Real-World Evidence of Daratumumab Monotherapy in Relapsed/Refractory Multiple Myeloma Patients and Efficacy on Soft-Tissue Plasmacytomas

INTRODUCTION

Daratumumab is an anti-CD38 agent that was first investigated as single agent in GEN501 and SIRIUS trials in patients with advanced multiple myeloma (MM). Overall response rate (ORR) was 30% with positive impact on progression-free survival (PFS). However, there is a lack of information regarding plasmacytoma response.

MATERIALS AND METHODS

Here, we described a heavily pretreated group of 43 patients who received daratumumab monotherapy after EMA approval and focused on plasmacytoma response.

RESULTS

After a median follow-up of 26 months, median time to best response was 2.9 months (range 0.8-13.1), median PFS was 5.2 months (95% CI 2.5 - 8.8) and median OS was 11.2 months (95% CI 6.3 - 17.0). Patients who achieved at least partial response had longer median PFS and OS (12.8 and 20.2 months, respectively) than those who achieved minimal response or stable disease (5.3 and 11.2 months, respectively). Ten patients (23%) had plasmacytomas (70% paraskeletal, 30% extramedullary). The clinical benefit for patients with and without plasmacytomas was 20% versus 42%. A dissociation between serological and plasmacytoma response was observed in 40% of the patients. Thus, 50% of the patients with plasmacytomas achieved at least serological minimal response but only 20% had plasmacytoma response.

CONCLUSION

This is the first real-world study of daratumumab monotherapy that focuses on efficacy data regarding soft-tissue plasmacytomas in patients with relapsed/refractory mieloma, showing a limited benefit in this patient population.

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.

Bone-Related Extramedullary Disease in Newly Diagnosed Myeloma Patients is an Independent Poor Prognostic Predictor

Background

Bone-related extramedullary disease (EMD-B) is mass of clonal plasma cells derived from adjacent bone lesions and has obvious heterogeneities in clinical outcomes. This retrospective study aims to evaluate the treatment outcomes and long-term prognosis of newly diagnosed myeloma patients with EMD-B.

Methods

This was a retrospective study conducted in Beijing Chaoyang Hospital from January 1, 2010 to December 31, 2019. Seventy-seven newly diagnosed multiple myeloma patients with EMD-B were selected. Propensity score matching (1:2) was used to match patients with and without EMD-B. After matching, 132 patients without extramedullary disease (non-EMD) were included in the study. All patients received bortezomib-based regimens as induction therapy.

Results

After matching, baseline data of the 2 groups were comparable. The Cox regression analysis of patients with EMD-B showed that age, paravertebral lesions, and immunoglobulin D (IgD) type may have adverse effects on survival. Bone-related extramedullary disease at new diagnosis was a risk predictor of survival (hazard ration [HR] = 1.80, 95% confidence interval [CI]: 1.09-2.98, P = .022). The median survival time of the EMD-B group was significantly shorter than that of the non-EMD group (52 months vs 96 months, P = .043). Induction therapy did not show any significant differences in effectiveness between the 2 groups. Autologous stem cell transplantation (ASCT) significantly increased complete remission rate of patients with EMD-B (EMD-B vs non-EMD: no ASCT 15.7% vs 31.9%, P = .035; ASCT 42.3% vs 48.8%, P = .626) and improved their median overall survival rate (EMD-B vs non-EMD: no ASCT 49 months vs 75 months, P = .003; ASCT not reached vs 96 months, P = .505).

Conclusions

This study demonstrated that newly diagnosed myeloma patients with EMD-B had poor outcomes, which could be improved by ASCT.

Hypoxia–Immune-Related Gene SLC19A1 Serves as a Potential Biomarker for Prognosis in Multiple Myeloma

Background

Multiple myeloma (MM) remains an incurable malignant tumor of plasma cells. Increasing evidence has reported that hypoxia and immune status contribute to the progression of MM. In this research, the prognostic value of the hypoxia–immune-related gene SLC19A1 in MM was evaluated by bioinformatics analysis.

Method

RNA-sequencing (RNA-seq) data along with clinical information on MM were downloaded from the Gene Expression Omnibus (GEO) database. Consistent clustering analysis and ESTIMATE algorithms were performed to establish the MM sample subgroups related to hypoxia and immune status, respectively, based on the GSE24080 dataset. The differentially expressed analysis was performed to identify the hypoxia–immune-related genes. Subsequently, a hypoxia–immune-gene risk signature for MM patients was constructed by univariate and multivariate Cox regression analyses, which was also verified in the GSE4581 dataset. Furthermore, the mRNA expression of SLC19A1 was determined using qRT-PCR in 19 MM patients, and the correlations between the genetic expression of SLC19A1 and clinical features were further analyzed.

Result

A total of 47 genes were identified as hypoxia–immune-related genes for MM. Among these genes, SLC19A1 was screened to construct a risk score model that had better predictive power for MM. The constructed prognostic signature based on SLC19A1 was verified in the GSE4581 dataset. All independent prognostic factors (age, β₂-microglobulin, LDH, albumin, MRI, and gene risk score) were used to develop a nomogram that showed a better performance for predicting the survival probability of MM patients for 1–5 years. Furthermore, SLC19A1 was highly expressed in newly diagnosed and relapsed MM patients, and high expression of SLC19A1 is correlated with higher bone marrow aspiration plasma cells and β₂-microglobulin levels in MM patients.

Conclusion

In conclusion, our results suggest that SLC19A1 is aberrantly expressed in MM and highly expressed SLC19A1 might be a biomarker correlated with inferior prognosis. More importantly, we identified SLC19A1 as a hypoxia–immune-related gene in MM. Future functional and mechanistic studies will further clarify the roles of SLC19A1 in MM.

Prognostic Value of Association of Copy Number Alterations and Cell-Surface Expression Markers in Newly Diagnosed Multiple Myeloma Patients

Multiple myeloma results from the clonal proliferation of abnormal plasma cells (PCs) in the bone marrow (BM). In this study, the cell surface expression markers (CD) on atypical PCs (detected by multiparametric flow cytometry (MFC)) were correlated with copy number alterations (CNAs) in the genome (detected by multiplex ligation-dependent probe amplification (MLPA)) to assess their impact on prognosis in newly diagnosed MM patients. Statistically significant results were obtained when different stages of PC maturation (classified based on CD19 and CD81 expression) were associated with CD117 expression and identified CNAs. In the intermediately differentiated PC group (CD19(−) CD81(+)), patients who didn’t express CD117 had a lower median progression free survival (PFS) (p = 0.024). Moreover, within this group, patients with less than three adverse CNAs, which harbor CD117, had a better outcome with a PFS of more than 48 months compared with 19 months (p = 0.008). Considering all the results, our study suggested the need to integrate both the CD markers and copy number alterations to evaluate the prognosis of newly diagnosed multiple myeloma patients.

Perspectives on the Risk-Stratified Treatment of Multiple Myeloma

The multiple myeloma treatment landscape has changed dramatically. This change, paralleled by an increase in scientific knowledge, has resulted in significant improvement in survival. However, heterogeneity remains in clinical outcomes, with a proportion of patients not benefiting from current approaches and continuing to have a poor prognosis. A significant proportion of the variability in outcome can be predicted on the basis of clinical and biochemical parameters and tumor-acquired genetic variants, allowing for risk stratification and a more personalized approach to therapy. This article discusses the principles that can enable the rational and effective development of therapeutic approaches for high-risk multiple myeloma.

Targeting the oncogenic transcription factor c-Maf for the treatment of multiple myeloma

Multiple myeloma (MM) is a hematologic malignancy derived from clonal expansion of plasma cells within the bone marrow and it may progress to the extramedullary region in late stage of the disease course. c-Maf, an oncogenic zipper leucine transcription factor, is overexpressed in more than 50% MM cell lines and primary species in association with chromosomal translocation, aberrant signaling transduction and modulation of stability. By triggering the transcription of critical genes including CCND2, ITGB7, CCR1, ARK5, c-Maf promotes MM progress, proliferation, survival and chemoresistance. Notably, c-Maf is usually expressed at the embryonic stage to promote cell differentiation but less expressed in healthy adult cells. c-Maf has long been proposed as a promising therapeutic target of MM and a panel of small molecule compounds have been identified to downregulate c-Maf and display potent anti-myeloma activities. In the current article, we take a concise summary on the advances in c-Maf biology, pathophysiology, and targeted drug discovery in the potential treatment of MM.

Presence of bone marrow fibrosis in multiple myeloma may predict extramedullary disease

We analyzed the incidence of bone marrow fibrosis in 91 newly diagnosed Japanese multiple myeloma (MM) patients and evaluated the impact of fibrosis on clinical characteristics and therapeutic outcomes. Thirty-four (37%) patients had greater than grade 1 bone marrow fibrosis. The presence of bone marrow fibrosis did not affect laboratory data, the percentage of plasma cells in bone marrow or cytogenetic findings. It also had no significant effect on response to initial treatment, engraftment after autologous hematopoietic stem cell transplantation or overall survival. Interestingly, the incidence of extramedullary disease at diagnosis was significantly higher in patients with bone marrow fibrosis (p = 0.006). Analysis of biological characteristics of MM cells revealed that expression of CD49e, an alpha5/beta1 integrin, was downregulated in MM cells derived from patients with bone marrow fibrosis (p = 0.026). When seven of the original 34 patients were re-evaluated for fibrosis grading after treatment, five (71%) showed a reduction in fibrosis. Our present findings suggest that the presence of bone marrow fibrosis may predict development of extramedullary disease in MM.

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.

Risk Stratification Before and During Treatment in Newly Diagnosed Multiple Myeloma: From Clinical Trials to the Real-World Setting

Multiple Myeloma (MM) is a hematologic malignancy characterized by a wide clinical and biological heterogeneity leading to different patient outcomes. Various prognostic tools to stratify newly diagnosed (ND)MM patients into different risk groups have been proposed. At baseline, the standard-of-care prognostic score is the Revised International Staging System (R-ISS), which stratifies patients according to widely available serum markers (i.e., albumin, β 2-microglobulin, lactate dehydrogenase) and high-risk cytogenetic abnormalities detected by fluorescence in situ hybridization. Though this score clearly identifies a low-risk and a high-risk population, the majority of patients are categorized as at “intermediate risk”. Although new prognostic factors identified through molecular assays (e.g., gene expression profiling, next-generation sequencing) are now available and may improve risk stratification, the majority of them need specialized centers and bioinformatic expertise that may preclude their broad application in the real-world setting. In the last years, new tools to monitor response and measurable residual disease (MRD) with very high sensitivity after the start of treatment have been developed. MRD analyses both inside and outside the bone marrow have a strong prognostic impact, and the achievement of MRD negativity may counterbalance the high-risk behavior identified at baseline. All these techniques have been developed in clinical trials. However, their efficient application in real-world clinical practice and their potential role to guide treatment-decision making are still open issues. This mini review will cover currently known prognostic factors identified before and during first-line treatment, with a particular focus on their potential applications in real-world clinical practice.

Identification of High-Risk Multiple Myeloma With a Plasma Cell Leukemia-Like Transcriptomic Profile

Primary plasma cell leukemia (pPCL) is an aggressive subtype of multiple myeloma, which is distinguished from newly diagnosed multiple myeloma (NDMM) on the basis of the presence of ≥ 20% circulating tumor cells (CTCs). A molecular marker for pPCL is currently lacking, which could help identify NDMM patients with high-risk PCL-like disease, despite not having been recognized as such clinically.

Recurrent extramedullary plasmacytomas without multiple myeloma: A case report with review of the literature

BACKGROUND

Extramedullary plasmacytoma (EMP) is an uncommon presentation and usually occurs in conjunction with multiple myeloma (MM). An EMP without developing MM at any point is an extremely rare presentation, and only seven such cases have been reported in the literature to date.

PRESENTATION OF CASE

We present a case of EMP, who presented with multiple recurrent lesions in rare sites like nasal cavity, testis and skin without the involvement of bone marrow at any point of disease course. He was treated with multiagent chemotherapy (DT-PACE) and continues to be in remission at 29 months post-chemotherapy, which is the longest amongst all the cases reported so far.

DISCUSSION AND CONCLUSIONS

There are no clearly defined guidelines to treat EMP. Our case had a clinical presentation at very unusual sites and was treated with DT-PACE regimen as against the previous seven reported cases and had the most prolonged period of remission.

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.

Serum Abnormal Metabolites for Evaluating Therapeutic Response and Prognosis of Patients With Multiple Myeloma

Aims

To evaluate abnormal metabolites related to treatment response and prognosis of multiple myeloma (MM) patients through ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS).

Methods

Forty-six symptomatic MM patients were included in this study who had a prior high level of positive monoclonal proteins before receiving targeted therapy with bortezomib-based regimens. UPLC-MS along with traditional immunofixation was performed on MM diagnostic samples and effective serum samples, and UPLC-MS was used to target valuable metabolic markers related to M protein.MM patients were segregated into pre-therapy (pre-T) and post-therapy (post-T) groups according to the response after chemotherapy. A monoclonal protein could be detected at baseline in 33 newly diagnosed MM (NDMM), 13 refractory and relapsed MM (RRMM) patients and 20 healthy controls (HC) by immunofixation.

Results

Between pre-T and post-T patients, the data showed that 32, 28 and 3 different metabolites were significantly correlated with M protein in IgG, IgA and light chain-type MM, respectively. These identified metabolites were significantly enriched in arginine and proline metabolism as well as glycerophospholipid metabolism pathways. Among them, PC (19:0/22:2) was displayed to increase significantly and consistently with M protein in each subtype of MM after treatment, which obviously indicated that it was related to the treatment response of MM. Further survival analysis of metabolic markers found that aspartic acid, LysoPE (16:0), SM (d18:1/17:0), PC (18:0/24:1), PC (16:0/16:0), TG (18:1/18:1/22:5) and LysoPE (18:2) reaching a certain cutoff value may be associated with shorter progression free survival (PFS). Finally, Cox multivariate regression analysis identified three factors were independent prognostic factors of MM. Moreover, there were significantly different in PC (19:0/22:2) and in aspartic acid between MM patients and healthy people.

Conclusion

This work identified significant metabolic disorders in 46 pairs off pre- and post-therapy MM patients, specifically in arginine, proline and glycerophospholipid pathways. The abnormal metabolites have the potential to serve as new biomarkers for evaluating treatment response and prognosis, as well as early monitoring of disease activity. Therefore, these systematic studies on abnormal metabolites as biomarkers for diagnosis and treatment will provide the evidence for future precise treatment of MM.

The mechanisms of mutual relationship between malignant hematologic cells and mesenchymal stem cells: Does it contradict the nursing role of mesenchymal stem cells?

Mesenchymal stem/stromal cells (MSCs) are known as the issue in biology because of some unpredictable characteristics in the different microenvironments especially in their bone marrow niche. MSCs are used in the regenerative medicine because of their unique potentials for trans-differentiation, immunomodulation, and paracrine capacity. But, their pathogenic and pro-survival effects in tumors/cancers including hematologic malignancies are indisputable. MSCs and/or their derivatives might be involved in tumor growth, metastasis and drug resistance in the leukemias. One of important relationship is MSCs and hematologic malignancy-derived cells which affects markedly the outcome of disease. The communication between these two cells may be contact-dependent and/or contact-independent. In this review, we studied the crosstalk between MSCs and malignant hematologic cells which results the final feedback either the progression or suppression of blood cell malignancy. Video abstract.

A Model Perspective Explanation of the Long-Term Sustainability of a Fully Human BCMA-Targeting CAR (CT103A) T-Cell Immunotherapy

Different from canonical drugs, CAR T-cells are “living drugs”, which derived from patient’s own blood. Studies of the pharmacokinetics of CAR T-cells could improve our understanding of their efficacy, safety, optimal dosage, and other characterizes. We previously reported a phase I study of a novel fully human BCMA-targeting CAR (CT103A) in 18 patients with relapsed/refractory multiple myeloma. CT103A exhibited extraordinary persistence with low anti-drug antibody positivity. To figure out the pharmacokinetic characterizes and investigate the potential reason of CT103A’s long-term persistence, we established a population pharmacokinetic (PopPK) model of CT103A based on 18 patients cohort by applying nonlinear mixed-effects modeling and analyzed the CAR T-cell clonal evolution. The results suggested that extramedullary spreading was found to impair C_max and was therefore added as a covariate to the modified model. The model revealed tocilizumab and corticosteroids showed no impact on the CT103A expansion rate. No dominant clone existed in patients with persistently high peripheral CT103A by CAR integration sites analysis. Finally, patients with lower contraction rate constants and higher C_max as well as memory CT103A fraction could achieve better clinical responses. Taken together, this study developed a PopPK model of a fully human anti-BCMA CAR T-cell therapy, and summarized its model characteristics. We suggested that the long-term persistence of CT103A was attributed to the memory CAR T-cell fraction but not the clonal evolution. This study will improve people’s understanding of pharmacokinetics and PopPK of CAR T-cell immunotherapy.

Nontargeted and targeted metabolomics approaches reveal the key amino acid alterations involved in multiple myeloma

PURPOSE

Multiple myeloma (MM), a kind of malignant neoplasm of clonal plasma cells in the bone marrow, is a refractory disease. Understanding the metabolism disorders and identification of metabolomics pathways as well as key metabolites will provide new insights for exploring diagnosis and therapeutic targets of MM.

METHODS

We conducted nontargeted metabolomics analysis of MM patients and normal controls (NC) using ultra-high-performance liquid chromatography (UHPLC) combined with quadrupole time-of-flight mass spectrometry (Q-TOF-MS) in 40 cases of cohort 1 subjects. The targeted metabolomics analysis of amino acids using multiple reaction monitoring-mass spectrometry (MRM-MS) was also performed in 30 cases of cohort 1 and 30 cases of cohort 2 participants, to comprehensively investigate the metabolomics disorders of MM.

RESULTS

The nontargeted metabolomics analysis in cohort 1 indicated that there was a significant metabolic signature change between MM patients and NC. The differential metabolites were mainly enriched in metabolic pathways related to amino acid metabolism, such as protein digestion and absorption, and biosynthesis of amino acids. Further, the targeted metabolomics analysis of amino acids in both cohort 1 and cohort 2 revealed differential metabolic profiling between MM patients and NC. We identified 12 and 14 amino acid metabolites with altered abundance in MM patients compared to NC subjects, in cohort 1 and cohort 2, respectively. Besides, key differential amino acid metabolites, such as choline, creatinine, leucine, tryptophan, and valine, may discriminate MM patients from NC. Moreover, the differential amino acid metabolites were associated with clinical indicators of MM patients.

CONCLUSIONS

Our findings indicate that amino acid metabolism disorders are involved in MM. The differential profiles reveal the potential utility of key amino acid metabolites as diagnostic biomarkers of MM. The alterations in metabolome, especially the amino acid metabolome, may provide more evidences for elucidating the pathogenesis and development of MM.

Ablation of VLA4 in multiple myeloma cells redirects tumor spread and prolongs survival

Multiple myeloma (MM) is a cancer of bone marrow (BM) plasma cells, which is increasingly treatable but still incurable. In 90% of MM patients, severe osteolysis results from pathological interactions between MM cells and the bone microenvironment. Delineating specific molecules and pathways for their role in cancer supportive interactions in the BM is vital for developing new therapies. Very Late Antigen 4 (VLA4, integrin α₄β₁) is a key player in cell–cell adhesion and signaling between MM and BM cells. We evaluated a VLA4 selective near infrared fluorescent probe, LLP2A-Cy5, for in vitro and in vivo optical imaging of VLA4. Furthermore, two VLA4-null murine 5TGM1 MM cell (KO) clones were generated by CRISPR/Cas9 knockout of the Itga4 (α₄) subunit, which induced significant alterations in the transcriptome. In contrast to the VLA4⁺ 5TGM1 parental cells, C57Bl/KaLwRij immunocompetent syngeneic mice inoculated with the VLA4-null clones showed prolonged survival, reduced medullary disease, and increased extramedullary disease burden. The KO tumor foci showed significantly reduced uptake of LLP2A-Cy5, confirming in vivo specificity of this imaging agent. This work provides new insights into the pathogenic role of VLA4 in MM, and evaluates an optical tool to measure its expression in preclinical models.

BCMA CAR-T Therapy Is Safe and Effective for Refractory/Relapsed Multiple Myeloma With Central Nervous System Involvement

Central nervous system (CNS) involvement is a rare complication of multiple myeloma (MM) that portends an extremely poor prognosis. Although chimeric antigen receptor (CAR)-T cell therapy is considered a promising strategy for patients with MM, the role of CAR-T cell therapy in MM involving the CNS has not been fully elucidated. In this study, we retrospectively analyzed 4 cases of B-cell maturation antigen CAR-T cell therapy for patients with relapsed/refractory MM involving the CNS. Patients received a range of 2-7 lines of prior therapy, including 1 autologous hematopoietic stem cell transplant. The most common adverse event was cytokine release syndrome, which was observed in all 4 patients, including 2 with grade 1 and 2 with grade 2. No patient was complicated with immune effector cell-associated neurotoxicity syndrome. Within the follow-up (median: 257 d, range: 116-392 d), 3 of 4 patients reached complete remission (CR), and 1 patient reached partial response. At the data cutoff, 1 patient continued to remain in CR at day 220, and the patient with partial response died at day 116. The other 2 patients relapsed at 317 and 111 days with CR durations of 287 and 81 days, respectively. Our results show promising effectiveness and acceptable safety of CAR-T cell therapy for heavily pretreated patients with CNS MM.

Efficacy and follow-up of humanized anti-BCMA CAR-T cell therapy in relapsed/refractory multiple myeloma patients with extramedullary-extraosseous, extramedullary-bone related, and without extramedullary disease

The prognosis of patients with multiple myeloma (MM) with extramedullary disease (EMD) remains poor. A high overall response rate (ORR) has been reported following anti‐B‐cell maturation antigen (BCMA) chimeric antigen receptor (CAR)‐T cell therapy in relapsed/refractory (R/R) patients with MM; however, data on patients with EMD remain limited. Herein, we compared and analyzed the efficacy and long‐term follow‐up of anti‐BCMA CAR‐T cell therapy in R/R MM patients with extramedullary‐extraosseous (EM‐E), extramedullary‐bone related (EM‐B), and without extramedullary disease. No difference in the ORR was observed between the three groups. The long‐term efficacy of anti‐BCMA CAR‐T cell therapy in the EM‐E group was worse than that in patients without EMD and with EM‐B. In the EM‐E group, disease progression was the reappearance of extramedullary lesions without an increase in the MM cell percentage or M protein level. Although no difference in the proportion of CAR‐T cells was detected among the three groups, the EM‐E group might exhibit a relatively high grade of cytokine release syndrome following anti‐BCMA CAR‐T therapy. Interleukin‐6 levels in the without EMD group were lower than those in the EM‐E and EM‐B groups. However, given the small number of cases in the three groups, statistical analysis was not performed.(ChiCTR1800017051 and ChiCTR2000033925).

The Safety of Bridging Radiation with Anti-BCMA CAR T-Cell Therapy for Multiple Myeloma

PURPOSE

B-cell maturation antigen (BCMA)-targeted chimeric antigen receptor (CAR) T cells (CART-BCMA) are a promising treatment for relapsed/refractory multiple myeloma (r/rMM). We evaluated the safety and feasibility of bridging radiation (RT) in subjects treated on a phase I trial of CART-BCMA.

EXPERIMENTAL DESIGN

Twenty-five r/rMM subjects were treated in three cohorts with two doses of CART-BCMA cells ± cyclophosphamide. We retrospectively analyzed toxicity, response, and CART manufacturing data based on RT receipt.

RESULTS

Thirteen subjects received no RT <1 year before CART infusion (Group A). Eight subjects received RT <1 year before CART infusion (Group B) with median time from RT to apheresis of 114 days (range 40-301). Four subjects received bridging-RT (Group C) with a median dose of 22 Gy and time from RT to infusion of 25 days (range 18-35). Group C had qualitatively lower rates of grade 4 (G4) hematologic toxicities (25%) versus A (61.5%) and B (62.5%). G3-4 neurotoxicity occurred in 7.7%, 25%, and 25% in Group A, B, and C, respectively. G3-4 cytokine release syndrome was observed in 38.5%, 25%, and 25% in Group A, B, and C, respectively. Partial response or better was observed in 54%, 38%, and 50% of Group A, B, and C, respectively. RT administered <1 year (P = 0.002) and <100 days (P = 0.069) before apheresis was associated with lower in vitro proliferation during manufacturing; however, in vivo CART-BCMA expansion appeared similar across groups.

CONCLUSIONS

Bridging-RT appeared safe and feasible with CART-BCMA therapy in our r/rMM patients, though larger future studies are needed to draw definitive conclusions.

Risk Factors Associated with Durable Progression-Free Survival in Patients with Relapsed or Refractory Multiple Myeloma Treated with Anti-BCMA CAR T-cell Therapy

PURPOSE

B-cell maturation antigen (BCMA) chimeric antigen receptor (CAR) T-cell therapy results in high remission rates in patients with relapsed/refractory (R/R) multiple myeloma. However, the factors associated with prognosis following CAR T-cell therapy are unknown.

PATIENTS AND METHODS

Between July 1, 2018 and July 31, 2020, 61 patients with R/R multiple myeloma received anti-BCMA CAR T-cell therapy (Chictr.org number, ChiCTR1800017404). Step-wise multivariate Cox regression and competing risk analyses were conducted to identify poor prognosis-associated risk factors.

RESULTS

Sixty patients (98.4%) experienced cytokine release syndrome (CRS), including 33, 23, and 4 cases of CRS grades 1 to 2, 3, and 4, respectively. The objective response rate (ORR) was 98.3%, and the complete remission (CR) rate was 70.3%. With a median follow-up period of 21.1 months, the 1-year overall survival (OS) and progression-free survival (PFS) rates were 78.0% and 50.2%, respectively. The median PFS was 12.7 months. Cox modeling revealed that poor PFS was associated with extramedullary disease [HR = 2.59, 95% confidence interval (95% CI) = 1.29-5.21, P = 0.008], light chain multiple myeloma (HR = 2.53, 95% CI = 1.03-5.97, P = 0.035), high-risk cytogenetics (HR = 2.80, 95% CI = 1.27-6.14, P = 0.01), and prior treatment with more than 3 therapeutic lines (HR = 3.14, 95% CI = 1.34-7.34, P = 0.008). Among the 41 CR cases, competing risk analyses demonstrated higher relapse predispositions in those with extramedullary disease (HR = 4.51, 95% CI = 1.86-10.9, P = 0.001), light chain multiple myeloma (HR = 4.89, 95% CI = 1.52 - 15.7, P = 0.008), or high-risk cytogenetics (HR = 5.09, 95% CI = 1.63-15.9, P = 0.005).

CONCLUSIONS

Anti-BCMA CAR T-cell therapy is safe and effective for R/R multiple myeloma. For patients with high-risk factors, improvements to extend remission and more specific individualized therapies are needed.

Comprehensive meta-analysis of anti-BCMA chimeric antigen receptor T-cell therapy in relapsed or refractory multiple myeloma

BACKGROUND

Chimeric antigen receptor (CAR) T-cell therapy shows impressive results in clinical trials. We conducted a meta-analysis based on the most recent data to systematically describe the efficacy and safety of anti-BCMA CAR T therapy for patients with relapsed or refractory multiple myeloma (R/R MM).

METHODS

PubMed, Embase, Web of Science, Cochrane library, ClinicalTrials.gov, China Biology Medicine disc (CBM disc) and Wanfang Data were searched on 8 November 2020. Registration number of PROSPERO was CRD42020219127.

RESULTS

From 763 articles, we identified 22 appropriate studies with 681 patients. The pooled overall response rate (ORR) was 85.2% (95%CI 0.797-0.910), complete response rate (CRR) was 47.0% (95%CI 0.378-0.583), and minimal residual disease (MRD) negativity rate was 97.8% (95%CI 0.935-1.022). The pooled incidence of grade 3-4 cytokine release syndrome was 6.6% (95%CI 0.036-0.096) and neurotoxicity was 2.2% (95%CI 0.006-0.038). The median progression-free survival (PFS) was 14.0 months and median overall survival (OS) was 24.0 months. Subgroup analysis showed dual epitope-binding CAR T cells achieved the best therapy outcomes and humanized CAR T cells had the best safety profile. Patients who were older, heavily pre-treated or received lower dose of CAR T cells had worse ORR. There was no significant difference in ORR, CRR and PFS between patients with and without high-risk cytogenetic features. The PFS and CRR of non-extramedullary disease (EMD) group was superior to those of EMD group.

CONCLUSION

Anti-BCMA CAR T therapy is effective and safe for patients with R/R MM. It can improve the prognosis of patients with high-risk cytogenetic features while the prognosis of patients with EMD remains poor. Moreover, patients are likely to benefit from an earlier use of CAR T therapy and human-derived CAR T cells have obvious advantages based on the existing data.

Stratification for RRMM and Risk-Adapted Therapy: Sequencing of Therapies in RRMM

The treatment landscape for relapsed multiple myeloma (RRMM) has experienced an unprecedented wave of innovation. Implementation of numerous new substances and drug classes with different modes of action is made possible in routine clinical practice. Next generation proteasome inhibitors, monoclonal antibodies, as well as first in class agents such as selinexor and venetoclax have widened the therapeutic spectrum. This has led to an increase in progression-free and overall survival. Consequently, new challenges for treating physicians in choosing the right treatment at the right stage of the disease have been generated. Several trials support the use of novel agents in the frontline treatment of newly diagnosed multiple myeloma. The use of lenalidomide or bortezomib as a backbone in the first-line setting, requires strategies for treatment once these patients relapse and are refractory to these drugs. Despite the variety of options, selecting the optimal treatment strategy is difficult, since multiple factors have to be considered: patient-specific factors such as age and co-morbidities, as well as myeloma/tumor specific factors such as cytogenetics and relapse kinetics. This review intends to summarize the existing data and guidelines regarding the optimal sequencing of treatments of RRMM using already approved agents as well as agents under investigation.

Updated Perspectives on the Management of Relapsed and Refractory Multiple Myeloma

BACKGROUND

With the availability of T-cell-directed therapy and next-generation compounds of established classes of drugs, the treatment of relapsed/refractory (r/r) myeloma is getting more complex. However, treatment options in practice are limited by availability, approval, and patient comorbidity. The aim of this article is to provide a practical approach toward the choice of treatment for r/r myeloma patients.

SUMMARY

Regarding market authorization and current guidelines, at least in Germany, most patients nowadays will have received a doublet or triplet combination as first-line therapy containing a proteasome inhibitor and an immunomodulatory drug, mostly lenalidomide. We focus on the treatment options for patients that are ineligible for (another) stem cell transplantation. We will review treatment options for relapse after first- or second-line therapy and beyond third-line. Key Messages: There is promising data supporting the efficacy and safety of triplet combinations containing anti-CD38-monoclonal antibodies (anti-CD38 mAbs) at first or second relapse in combination with next-generation compounds. For the treatment beyond third-line, comparative studies are scarce but some promising compounds are available via conditional authorization, and there is more to come in the future. We will present some early phase trials featuring promising results.

Extramedullary relapse in a patient with multiple myeloma: a rare cause of gastrointestinal perforation and massive bleeding

Multiple myeloma (MM) patients live longer due to more effective treatment, and we now see previously uncommon manifestations of MM, like extramedullary disease. We present a case of a 74-year-old man known with MM that relapsed with extramedullary manifestations at different locations. One of them as a gastric plasmacytoma (GP). He was successfully treated with chemoradiotherapy (Daratumumab, Bortezomib and Dexamethasone), which resulted in clinical response for 8 months, confirmed by biopsy and histopathology. Perforation of the GP occurred, and he underwent partial gastrectomy (Billroth II gastrojejunostomy). The patient's disease progressed again 5 months after surgery, and he did not want any additional treatment. He accepted palliative care and died 10 months after the operation. A lack of knowledge about the characteristics and treatment of extramedullary MM exists, and prospective studies to investigate incidence, prognosis and treatment for extramedullary MM are needed for improving the poor prognosis of this manifestation.

Anti-BCMA CAR-T Cell Therapy in Relapsed/Refractory Multiple Myeloma Patients With Extramedullary Disease: A Single Center Analysis of Two Clinical Trials

Background

The prognosis of relapsed/refractory multiple myeloma (RRMM) patients with the extramedullary disease was significantly poor. Extramedullary multiple myeloma (EMM) patients gained limited benefits from traditional drugs. Anti-B cell maturation antigen (BCMA) chimeric antigen receptor (CAR) T-cell therapy seems to be a promising approach to treat RRMM patients. However, very few clinical studies are designed for EMM. Our study aimed to compare and assess the safety, efficacy, and pharmacokinetics of anti-BCMA CAR-T cell therapy in EMM and non-EMM.

Methods

The results from published anti-BCMA CAR-T clinical trials, in which raw data of EMM patients were available, were reviewed and summarized. Two trials conducted in our clinical centers were analyzed and presented with detailed data.

Results

According to published anti-BCMA CAR-T clinical trials, the ORR of EMM ranged from 57% to 100%, with the complete remission (CR) rate of 29% to 60%. Between February 22, 2017, and September 26, 2019, a total of 61 subjects (EMM 25; non-EMM 36) received anti-BCMA CAR-T cell infusion. The data-cutoff date was April 1, 2021. There were no statistical differences between EMM and non-EMM groups in adverse events (AEs), including cytokine release syndrome (CRS). The most common AEs of grade ≥ 3 in both groups were hematologic toxicities. There was no significant difference in the objective response rate (ORR) and ≥ complete remission (CR) rate between both groups. However, the ≥ CR rate of the EMM group was lower than the non-EMM group receiving the fully human anti-BCMA CAR-T cell therapy (p = 0.026). The median progression-free survival (PFS) for EMM and the non-EMM group was 121 days and 361 days, respectively (p = 0.001). The median overall survival (OS) for EMM and the non-EMM group was 248 days and 1024 days, respectively (p = 0.005). The C_max and AUC_0-28d for EMM group were lower than non-EMM group (C_max, p = 0.016; AUC_0-28d, p = 0.016). Extramedullary disease was an independent prognostic risk factor for PFS (hazard ratio, 2.576; 95% CI, 1.343 to 4.941; p = 0.004) and OS (hazard ratio, 2.312; 95% CI, 1.165 to 4.592; p = 0.017) in RRMM patients receiving anti-BCMA CAR-T cell therapy.

Conclusions

Based on our results, EMM patients could benefit from the two anti-BCMA CAR products, although they had a shorter PFS and OS compared with non-EMM patients.

Clinical Trial Registration

http://www.chictr.org.cn, identifier ChiCTR-OPC-16009113 and ChiCTR1800018137.

Multiple Myeloma: Molecular Pathogenesis and Disease Evolution

BACKGROUND

Multiple myeloma is the second most common hematologic malignancy, which to date remains incurable despite advances in treatment strategies including the use of novel substances such as proteasome inhibitors, immunomodulatory drugs, and monoclonal antibodies.

SUMMARY

The bone marrow-based disease is preceded by the 2 sequential premalignant conditions: monoclonal gammo-pathy of undetermined significance and smoldering myeloma. Plasma cell leukemia and extramedullary disease occur, when malignant clones lose their dependency on the bone marrow. Key genetic features of these plasma cell dyscrasias include chromosomal aberrations such as translocations and hyperdiploidy, which occur during error-prone physiologic processes in B-cell development. Next-generation sequencing studies have identified mutations in major oncogenic pathways and tumor suppressors, which contribute to the pathogenesis of multiple myeloma and have revealed insights into the clonal evolution of the disease, particularly along different lines of therapy. More recently, the importance of epigenetic alterations and the role of the bone marrow microenvironment, including immune and osteogenic cells, have become evident. Key Messages: We herein review the current knowledge of the pathogenesis of multiple myeloma, which is crucial for the development of novel targeted therapeutic strategies. These can contribute to the endeavor to make multiple myeloma a curable disease.

Outcomes of VDPACE with an immunomodulatory agent as a salvage therapy in relapsed/refractory multiple myeloma with extramedullary disease

Extramedullary disease (EMD) is an aggressive form of multiple myeloma (MM). Confirming the presence of plasma cells outside the bone marrow makes the diagnosis of EMD. There is no clear consensus on the management of EMD in MM, and this entity continues to remain an unmet need. Rapidly controlling EMD to prevent end-organ damage is a priority. Retrospectively, we reviewed our database for patients with EMD that received treatment with bortezomib, dexamethasone, cisplatin, doxorubicin, cyclophosphamide, etoposide (VDPACE) plus an immune modulator (IMiD) regimen. We identified 21 patients with a median age of 61 years. Ten patients received a VDPACE based regimen as a bridge to autologus stem cell transplant (ASCT). After a median follow-up of 51.4 months, the median overall survival (OS) and progression-free survival were 14.9 months (95% CI: 7.8-NA) and 5.5 months (95% CI: 3.9-NA), respectively. The overall response rate was 76%, with a manageable safety profile. Interestingly, these results were similar regardless of the presence of high-risk cytogenetics. The safety profile was acceptable. In conclusion, a salvage VDPACE-based regimen plus an IMiD remains an effective and safe bridging therapy to future ASCT and immunotherapy in relapsed/refractory multiple myeloma patients with EMD.

Improved survival of multiple myeloma patients treated with autologous transplantation in the modern era of new medicine

New drugs for multiple myeloma (MM) have dramatically improved patients’ overall survival (OS). Autologous stem cell transplantation (ASCT) remains the mainstay for transplant‐eligible MM patients. To investigate whether the post‐ASCT prognosis of MM patients has been improved by new drugs, we undertook a retrospective observational analysis using the Transplant Registry Unified Management Program database in Japan. We analyzed 7323 patients (4135 men and 3188 women; median age, 59 years; range 16‐77 years) who underwent upfront ASCT between January 2007 and December 2018. We categorized them by when they underwent ASCT according to the drugs’ introduction in Japan: group 1 (2007‐2010), group 2 (2011‐2016), and group 3 (2017‐2018). We compared the groups’ post‐ASCT OS. The 2‐year OS rates (95% confidence interval [CI]) of groups 1, 2, and 3 were 85.8% (84.1%‐87.4%), 89.1% (88.0%‐90.1%), and 92.3% (90.0%‐94.2%) (P < .0001) and the 5‐year OS (95% CI) rates were 64.9% (62.4%‐67.3%), 71.6% (69.7%‐73.3%), and not applicable, respectively (P < .0001). A multivariate analysis showed that the post‐ASCT OS was superior with these factors: age less than 65 years, performance status 0/1, low International Staging System (ISS) stage, receiving SCT for 180 days or less post‐diagnosis, better treatment response pre‐ASCT, later year of ASCT, and receiving SCT twice. A subgroup analysis showed poor prognoses for the patients with unfavorable karyotype and poor treatment response post‐ASCT. The post‐ASCT OS has thus improved over time (group 1 < 2 < 3) with the introduction of new drugs for MM. As the prognosis of high‐risk‐karyotype patients with ISS stage III remains poor, their treatment requires improvement.

Pathophysiological role of calcium channels and transporters in the multiple myeloma

Multiple myeloma (MM) is a common malignant tumor of plasma cells. Despite several treatment approaches in the past two decades, MM remains an aggressive and incurable disease in dire need of new treatment strategies. Approximately 70–80% of patients with MM have myeloma bone disease (MBD), often accompanied by pathological fractures and hypercalcemia, which seriously affect the prognosis of the patients. Calcium channels and transporters can mediate Ca²⁺ balance inside and outside of the membrane, indicating that they may be closely related to the prognosis of MM. Therefore, this review focuses on the roles of some critical calcium channels and transporters in MM prognosis, which located in the plasma membrane, endoplasmic reticulum and mitochondria. The goal of this review is to facilitate the identification of new targets for the treatment and prognosis of MM.

The Safety and Efficacy of Radiation Therapy with Concurrent Dexamethasone, Cyclophosphamide, Etoposide, and Cisplatin-Based Systemic Therapy for Multiple Myeloma

INTRODUCTION

The concurrent delivery of radiation therapy (RT) with salvage chemotherapies in the management of relapsed and refractory multiple myeloma (MM) is an area of ongoing investigation. This study examined the safety and efficacy of palliative RT given in the setting of concurrent dexamethasone, cyclophosphamide, etoposide, and cisplatin (DCEP).

PATIENTS AND METHODS

Fifty-five patients with MM received RT to 64 different sites within three weeks of receiving DCEP from 2010 to 2020. A median dose of 20 Gray (range 8-32.5 Gy) was delivered in a median of 5 fractions (range 1-15). Patients received a median of 1 cycle (range 1-5) of DCEP. Rates of hematologic and RT toxicity were recorded along with pain, radiographic, and laboratory responses to treatment.

RESULTS

RT was completed in 98% of patients. 21% of patients experienced RTOG grade 3+ hematologic toxicity before RT, which increased to 35% one-month post-RT (P = .13) before decreasing to 12% at 3 to 6 months (P = .02). The most common toxicity experienced was thrombocytopenia. Grade 1 to 2 non-hematologic RT-related toxicity was reported in 15% of patients while on treatment and fell to 6% one-month after completing RT. Pain resolved in 94% of patients with symptomatic lesions at baseline. Stable disease or better was observed in 34/39 (87%) of the targeted lesions on surveillance imaging.

CONCLUSION

RT administered concurrently with DCEP was well-tolerated by most of the patients in this series, with low rates of hematologic and RT-related toxicity. RT was also very effective, with the vast majority of patients demonstrating resolution of their pain and a significant response on follow-up imaging.

IgD multiple myeloma with central nervous system involvement: A case report and literature review

Central nervous system (CNS) involvement is a rare manifestation of multiple myeloma (MM) and the optimal management strategies have yet to be determined. The aim of the present study was to describe the case of a 47-year-old male patient with immunoglobulin D-λ MM who presented with multiple extramedullary infiltrations at diagnosis. This patient achieved stringent complete response after 9 cycles of treatment with bortezomib, lenalidomide and dexamethasone, and then received lenalidomide as maintenance therapy. CNS involvement and extramedullary relapse developed 3 months after the last chemotherapy cycle. Despite receiving a second-line treatment protocol, the patient succumbed to the disease within 1 month after recurrence. The characteristics and treatment options for CNS MM are discussed in this case report.

Clonal Evolution of Multiple Myeloma-Clinical and Diagnostic Implications

Plasma cell dyscrasias are a heterogeneous group of diseases characterized by the expansion of bone marrow plasma cells. Malignant transformation of plasma cells depends on the continuity of events resulting in a sequence of well-defined disease stages, from monoclonal gammopathy of undetermined significance (MGUS) through smoldering myeloma (SMM) to symptomatic multiple myeloma (MM). Evolution of a pre-malignant cell into a malignant cell, as well as further tumor progression, dissemination, and relapse, require development of multiple driver lesions conferring selective advantage of the dominant clone and allowing subsequent evolution under selective pressure of microenvironment and treatment. This process of natural selection facilitates tumor plasticity leading to the formation of genetically complex and heterogenous tumors that are notoriously difficult to treat. Better understanding of the mechanisms underlying tumor evolution in MM and identification of lesions driving the evolution from the premalignant clone is therefore a key to development of effective treatment and long-term disease control. Here, we review recent advances in clonal evolution patterns and genomic landscape dynamics of MM, focusing on their clinical implications.

Efficacy of Humanized Anti-BCMA CAR T Cell Therapy in Relapsed/Refractory Multiple Myeloma Patients With and Without Extramedullary Disease

In recent years, many new treatments for relapsed/refractory (R/R) multiple myeloma (MM) have improved patient prognosis, but the prognosis of patients with extramedullary MM is still particularly poor. Therefore, more efficacious therapies and novel strategies are urgently needed for these patients. The aim of this study was to observe and compare the efficacy and safety of humanized anti-B cell maturation antigen (anti-BCMA) chimeric antigen receptor (CAR) T cell therapy in R/R MM patients with and without extramedullary disease. Seven R/R MM patients with extramedullary disease and 13 without extramedullary disease received humanized anti-BCMA CAR T cell therapy. The overall response rate was not different between patients with and without extramedullary disease. There was no difference in the progression-free survival (PFS) or overall survival (OS) rates between the two groups at 180 days, but the PFS and OS rates in patients with extramedullary disease were lower at 360 days than those in patients without extramedullary disease. Although some patients with extramedullary disease experienced further disease progression, their M protein level did not increase. We did not see this change trend of M protein in patients without extramedullary disease. However, this was not observed in patients without extramedullary disease. Among patients who responded to CAR T cell therapy, the grades of cytokine release syndrome (CRS) and immune effector cell-associated neurotoxic syndrome (ICANS) were much higher among patients with extramedullary disease. In summary, R/R MM patients with extramedullary disease could benefit from humanized anti-BCMA CAR T cell therapy in the short term, although the CRS and ICANS grades were much higher in patients with extramedullary disease. Therefore, anti-BCMA CAR T cell therapy allows for a remission time for R/R MM patients with extramedullary disease, which could be maintained by bridging hematopoietic stem cell transplantation, radiotherapy, and other therapies.

Clinical Trial Registration

http://www.chictr.org.cn/index.aspx, identifiers ChiCTR1800017051 and ChiCTR2000033925.