Advances in the treatment of extramedullary disease in multiple myeloma

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.

Monoclonal antibodies - A repertoire of therapeutics

Antibodies are a class of biomolecules armed with extraordinary diversity, unmatched in the biological world by any other class of molecules. This characteristic feature equips antibodies to recognize, bind, and eliminate an infinite number of pathogens/antigens facilitated by their effector functions. The repertoire of natural binding specificities of antibodies (Abs) is greater than the calculated estimate of ∼1012 in humans, as a naive, single antigen-binding site may bind more than one antigen employing the plasticity in antigen-antibody interactions, potentiating Abs to fight infinite pathogenic insults and restrict the development of cancers. Additionally, advanced technological interventions, by allowing manipulation of the germline and acquired specificities of human/animal immunoglobulins (Ig) have contributed immensely to broaden their existing repertoire and scope of clinical applications. The available natural repertoire of Ig and Ig-like molecules in other animals, e.g., mice, horses, cows, pigs, rabbits, camels, llamas, etc., further diversified the source of unique antigen-binding specificities. The recombinant DNA technology, in association with hybridoma , transgenic, and phage display technologies, has helped create a parallel repertoire of unique antibody molecules [animal Abs, camelid heavy chain Abs (hcAbs), chimeric Abs, chimeric hcAbs, humanized Abs, humanized nanobody (Nb)-hcAbs, human Abs, etc.], monoclonal Ab (mAb) derived fragments [antigen-binding-fragment (Fab), single-chain-variable-fragment (scFv), variable-fragement (Fv), single-variable-domain of hcAbs (VHH), bispecific scFv, diabodies, triabodies, intrabodies, bispecific Fabs, tri-specific Fabs, etc.), and immunoconjugates generated by fusing/conjugating mAb fragments with enzyme, toxin, prodrug etc., molecules. The current chapter provides a detailed description of the natural and engineered antibody repertoires and discusses various strategies using which these molecules are being inducted as novel immunotherapeutics for treating a significant number of human diseases.

Multiple myeloma: clinical characteristics, current therapies and emerging innovative treatments targeting ribosome biogenesis dynamics

Multiple myeloma (MM) is a clinical disorder characterized by aberrant plasma cell growth in the bone marrow microenvironment. Globally, the prevalence of MM has been steadily increasing at an alarming rate. In the United States, more than 30,000 cases will be diagnosed in 2024 and it accounts for about 2% of cancer diagnoses and more than 2% of cancer deaths, more than double the worldwide figure. Both symptomatic and active MM are distinguished by uncontrolled plasma cell growth, which results in severe renal impairment, anemia, hypercalcemia, and bone loss. Multiple drugs have been approved by the FDA and are now widely used in clinical practice for MM. Although triplet and quadruplet induction regimens, autologous stem cell transplantation (ASCT), and maintenance treatment are used, MM continues to be an incurable illness characterized by relapses that may occur at various phases of its progression. MM patients with frailty, extramedullary disease, plasma cell leukemia, central nervous system recurrence, functional high risk, and the elderly are among those with the greatest current unmet needs. The high cost of care is an additional challenge. MM cells are highly protein secretary cells and thus are dependent on the activation of certain translation pathways. MM also has a high chance of altering ribosomal protein-encoding genes like MYC mutation. In this article we discuss the importance of ribosome biogenesis in promoting MM and RNA polymerase I inhibition as an upcoming treatment with potential promise for MM patients.

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.

Visual impairment as the initial presentation in multiple myeloma: a case report and literature review

Background

Multiple myeloma (MM) is a type of blood cancer, which rarely infiltrates the central nervous system (CNS) and lacks specific neurological symptoms. The prognosis is often poor, as the disease progresses rapidly. Herein, we present a rare case of MM with CNS involvement.

Case Description

A 53-year-old man was admitted to the Neurosurgery Department, Jinhua Hospital Affiliated to Zhejiang University with initial symptoms of "blurred vision for 3 months accompanied by numbness on the right side of the face for 7 days". Enhanced cranial magnetic resonance imaging revealed a tumor deep in the right temporal bone. During exploratory surgery, the "fleshy" mass was completely removed. Postoperative pathology confirmed a diagnosis of "plasmacytoma with intermediate features". The patient received multiple systematic chemotherapy treatments after surgery in the department of hematology of Jinhua Hospital Affiliated to Zhejiang University. During a 10-month follow-up period, the patient's neurological symptoms improved, and his general condition was considered good.

Conclusions

This report summarizes the clinical features, diagnosis, treatment, and prognosis of a patient with MM involving the CNS and examines the relevant literature. This case may serve as a reference for future clinical treatment and diagnosis. Further research on the pathophysiology of such cases is warranted.

BCMA-BBZ-OX40 CAR-T Therapy Using an Instant Manufacturing Platform in Multiple Myeloma

BACKGROUND

Chimeric antigen receptor (CAR)-T cell has revolutionary efficacy against relapsed/refractory multiple myeloma (R/R MM). However, current CAR-T cell therapy has several limitations including long vein-to-vein time and limited viability.

METHODS

A 4-1BB-costimulated B-cell maturation antigen (BCMA) CAR-T integrating an independently-expressed OX40 (BCMA-BBZ-OX40) was designed and generated by a traditional manufacturing process (TraditionCART) or instant manufacturing platform (named InstanCART). The tumor-killing efficiency, differentiation, exhaustion, and expansion level were investigated in vitro and in tumor-bearing mice. An investigator-initiated clinical trial was performed in patients with R/R MM to evaluate the outcomes of both TraditionCART and InstanCART. The primary objective was safety within 1 month after CAR-T cell infusion. The secondary objective was the best overall response rate.

RESULTS

Preclinical studies revealed that integrated OX40 conferred BCMA CAR-T cells with superior cytotoxicity and reduced exhaustion levels. InstanCART process further enhanced the proliferation and T-cell stemness of BCMA-BBZ-OX40 CAR-T cells. BCMA-BBZ-OX40 CAR-T cells were successfully administered in 22 patients with R/R MM, including 15 patients with TraditionCART and 7 patients with InstanCART. Up to 50% (11/22) patients had a high-risk cytogenetic profile and 36% (8/22) had extramedullary disease. CAR-T therapy caused grade 1-2 cytokine release syndrome in 19/22 (80%) patients, grade 1 neurotoxicity in 2/22 (9%) patients and led to ≥grade 3 adverse events including neutropenia (20/22, 91%), thrombocytopenia (15/22, 68%), anemia (12/22, 55%), creatinine increased (1/22, 5%), hepatic enzymes increased (5/22, 23%), and sepsis (1/22, 5%). The best overall response rate was 100%, and 64% (14/22) of the patients had a complete response or better. The median manufacturing time was shorter for InstanCART therapy (3 days) than for TraditionCART therapy (10 days). Expansion and duration were dramatically higher for InstanCART cells than for TraditionCART cells.

CONCLUSIONS

BCMA-BBZ-OX40 CAR-T cells were well tolerated and exhibited potent responses in patients with R/R MM. InstanCART shortened the manufacturing period compared to TraditionCART, and improved the cellular kinetics. Our results demonstrated the potency and feasibility of OX40-modified BCMA CAR-T cells using InstanCART technology for R/R MM therapy.

TRIAL REGISTRATION NUMBER

This trial was registered at www.

CLINICALTRIALS

gov as #NCT04537442.

Unveiling Multiple Myeloma: Actively Bleeding Extramedullary Gastric Myelomas Lead to Diagnosis

Multiple myeloma (MM) is a disease of plasma cell replication, leading to a disruption of hematopoiesis, which commonly presents clinically with anemia and fatigue. Extramedullary myelomas are plasma cell collections in bone or soft tissue associated with MM and most often occur later in the disease process. We present a case of a patient with symptomatic anemia with actively bleeding gastric nodules, which were later found to be extramedullary gastric myelomas when pathology demonstrated kappa-restricted plasma cell neoplasms. To confirm the overall diagnosis, a bone marrow biopsy verified the patient had MM.

Case report: An uncommon presentation of extramedullary plasmacytoma without a concurrent diagnosis of multiple myeloma

Introduction

Extramedullary plasmacytoma (EMP) is an uncommon solitary tumor originating from neoplastic plasma cells located outside the bone marrow. Despite its rarity, the occurrence of EMP without a concurrent diagnosis of multiple myeloma (MM) is considered extremely rare. Approximately 80-90% of EMP cases are found in the head and neck region, with a higher incidence in men aged between 50 and 60 years. The current treatment modalities include radiotherapy (RT) as a first-line approach, with surgery or chemotherapy regarded as other therapeutic options. While RT proves effective in the majority of EMP cases, there are instances where the tumor remains refractory to radiation. In this case report, we present an unusual scenario of EMP resistant to RT without concurrent signs of multiple myeloma which was successfully treated with surgery followed by systemic therapy.

Case report

A 72-year-old male was admitted to the Head and Neck Cancer Clinic with a 6-month history of swallowing difficulties. He denied experiencing weight loss or pain on swallowing. Basic laboratory tests yielded results within normal limits, except for beta-2 microglobulin. Physical examination revealed an enlarged submandibular lymph node on the right side. Fiberoptic examination identified a soft tissue polypoid mass within the right piriform fossa, slightly protruding into the vocal slit. A CT scan displayed a well-circumscribed 2 cm polypoid, homogeneously enhancing soft tissue mass adjacent to the posterior surface of the epiglottis and the right side of the tongue base. Bone marrow biopsy revealed no abnormalities, and there were no clinical or laboratory signs of multiple myeloma. Based on the tumor biopsy results and imaging studies, a diagnosis of EMP was made. Due to the lack of response to RT, surgical removal of the tumor was pursued, followed by systemic therapy. Ultimately, the patient achieved full recovery with effective disease control.

Conclusion

In conclusion, EMP without concurrent multiple myeloma is an exceedingly rare condition that demands a multidisciplinary approach for both diagnosis and treatment. Moreover, although RT continues to be the primary standard treatment for EMP, in some cases other therapeutic regimens prove to be successful.

CD38 expression by plasma cells in extramedullary multiple myeloma

Not available.

Plasmacytoma in the Maxillary Jaw: A Diagnostic and Therapeutic Challenge

Plasmacytoma is a neoplastic disorder originating from plasma cells, with bone and soft tissue being common sites of manifestation. This report presents the clinical and radiological findings of a 65-year-old female patient who presented with an exophytic lesion in the upper right lateral incisor region. The lesion appeared as a unilocular radiotransparent area in imaging tests. Following an excisional biopsy, histological and immunohistochemical evaluations confirmed the presence of mature plasmacellular elements and small infiltrates of B and T lymphocytes. The patient did not exhibit systemic manifestations of multiple myeloma. Surgical intervention, in the form of enucleation of the lesion combined with root canal treatment and apicoectomy, was performed. This case underscores the rare occurrence of plasmacytoma in the jaw region and highlights the importance of surgical management in cases where structural damage or functional impairment is present. Further research on novel treatment approaches is also mentioned, including targeted therapies, immunomodulatory agents, and monoclonal antibodies. The patient is currently under the care of a hematologist for further investigation and the choice of the most appropriate therapy.

Recurrence of solitary plasmacytoma in the liver 10 years after the onset of multiple bone lesions

A 79-year-old man presented with a history of solitary plasmacytoma in the bone 10 years ago. Chemoradiotherapy was effective, and remission was maintained with intermittent treatment at relapse of the bone lesions. One year after the last treatment, a follow-up computed tomography (CT) scan revealed multiple liver masses, and a liver biopsy revealed plasmacytoma. There was no clonal plasma cell infiltration in the bone marrow, and the final diagnosis was solitary plasmacytomas of the liver. Although liver involvement is known in relapsed refractory multiple myeloma, solitary plasmacytoma in the relapsed stage confined to the liver is rare, and all previous reports have been from the initial presentation. To the best of our knowledge, this is the first recurrent case of solitary plasmacytoma of the liver.

Advances in research on potential inhibitors of multiple myeloma

Multiple myeloma (MM) is a common hematological malignancy. Although recent clinical applications of immunomodulatory drugs, proteasome inhibitors and CD38-targeting antibodies have significantly improved the outcome of MM patient with increased survival, the incidence of drug resistance and severe treatment-related complications is gradually on the rise. This review article summarizes the characteristics and clinical investigations of several MM drugs in clinical trials, including their structures, mechanisms of action, structure-activity relationships, and clinical study progress. Furthermore, the application potentials of the drugs that have not yet entered clinical trials are also reviewed. The review also outlines the future directions of MM drug development.

A prognostic nomogram and risk classification system of elderly patients with extraosseous plasmacytoma: a SEER database analysis

BACKGROUND

The survival trends and prognostic factors of patients with extraosseous plasmacytoma (EOP) or extramedullary plasmacytoma (EMP) have not been reported in recent years. The objective of this study was to develop a novel nomogram and risk stratification system for predicting the overall survival (OS) of elderly patients with EOP based on the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

The demographic characteristics of 900 patients aged 60 years and above, diagnosed with EOP between 2000 and 2019, were extracted from the SEER database. The patient population was randomly divided into a training cohort and an internal validation cohort in a ratio of 7:3. Univariate and multivariate Cox regression analyses were conducted to identify independent predictors of prognosis in elderly EOP patients, followed by developing a nomogram for prognostic assessment. The performance of the model was evaluated through receiver-operating characteristic (ROC) curves, C-index, calibration curves for calibration accuracy assessment, and decision curve analysis (DCA) to assess its clinical utility. All elderly EOP patients were stratified into three risk subgroups by cutoff value utilizing X-tile software based on their total OS scores for comparative analysis purposes. Kaplan-Meier (K-M) survival curve analysis was employed to validate any observed differences in OS among these three risk groups.

RESULTS

Six factors including age, year of diagnosis, marital status, primary site, surgery, and prior tumor history were identified to be independently predictive of the OS of elderly patients with EOP, and these predictors were included in the construction of the nomogram. The 1-, 3-, and 5-year area under the curves (AUCs) for OS were 0.717, 0.754, and 0.734 in the training cohort and 0.740, 0.730, and 0.765 in the validation cohort, respectively. The C-index values in the two cohorts were 0.695 and 0.690. The calibration curves and DCA exhibit commendable consistency and validity, respectively, thereby demonstrating their robust performance. The training set was stratified into low-, medium-, and high-risk subgroups based on the optimal cutoff points (167.8 and 264.8) identified. The K-M curve and cumulative risk curve exhibited statistically significant disparities in survival rates among the groups.

CONCLUSIONS

We developed a nomogram and risk classification system, which can serve as an intuitive and effective tool for clinicians to enhance the prediction of OS in elderly EOP patients, thereby facilitating the formulation of more rational and personalized treatment strategies.

Multiple Myeloma in 2023 Ways: From Trials to Real Life

Multiple myeloma is a chronic hematologic malignancy that obstinately tends to relapse. Basic research has made giant strides in better characterizing the molecular mechanisms of the disease. The results have led to the manufacturing of new, revolutionary drugs which have been widely tested in clinical trials. These drugs have been approved and are now part of the therapeutic armamentarium. As a consequence, it is essential to combine what we know from clinical trials with real-world data in order to improve therapeutic strategies. Starting with this premise, our review aims to describe the currently employed regimens in multiple myeloma and compare clinical trials with real-life experiences. We also intend to put a spotlight on promising therapies such as T-cell engagers and chimeric antigen receptor T-cells (CAR-T) which are proving to be effective in changing the course of advanced-stage disease.

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.

Antitumoral effects of Bortezomib in malignant mesothelioma: evidence of mild endoplasmic reticulum stress in vitro and activation of T cell response in vivo

BACKGROUND

Malignant mesothelioma (MM) is a rare tumor with a dismal prognosis. The low efficacy of current treatment options highlights the urge to identify more effective therapies aimed at improving MM patients' survival. Bortezomib (Bor) is a specific and reversible inhibitor of the chymotrypsin-like activity of the 20S core of the proteasome, currently approved for the treatment of multiple myeloma and mantle cell lymphoma. On the other hand, Bor appears to have limited clinical effects on solid tumors, because of its low penetration and accumulation into tumor tissues following intravenous administration. These limitations could be overcome in MM through intracavitary delivery, with the advantage of increasing local drug concentration and decreasing systemic toxicity.

METHODS

In this study, we investigated the effects of Bor on cell survival, cell cycle distribution and modulation of apoptotic and pro-survival pathways in human MM cell lines of different histotypes cultured in vitro. Further, using a mouse MM cell line that reproducibly forms ascites when intraperitoneally injected in syngeneic C57BL/6 mice, we investigated the effects of intraperitoneal Bor administration in vivo on both tumor growth and the modulation of the tumor immune microenvironment.

RESULTS

We demonstrate that Bor inhibited MM cell growth and induced apoptosis. Further, Bor activated the Unfolded Protein Response, which however appeared to participate in lowering cells' sensitivity to the drug's cytotoxic effects. Bor also affected the expression of EGFR and ErbB2 and the activation of downstream pro-survival signaling effectors, including ERK1/2 and AKT. In vivo, Bor was able to suppress MM growth and extend mice survival. The Bor-mediated delay of tumor progression was sustained by increased activation of T lymphocytes recruited to the tumor microenvironment.

CONCLUSIONS

The results presented herein support the use of Bor in MM and advocate future studies aimed at defining the therapeutic potential of Bor and Bor-based combination regimens for this treatment-resistant, aggressive tumor.