Effective treatment of pomalidomide in central nervous system myelomatosis

Pomalidomide improves the effectiveness of CAR-T treatment in the relapsed and refractory multiple myeloma or B-cell leukemia/lymphoma with extramedullary disease

Relapsed and refractory multiple myeloma (RRMM) and B-cell leukemia/lymphoma with extramedullary disease (EMD) have poor prognosis and high mortality, lack of effective therapeutic approaches. We reported for the first time that 6 patients with malignant hematological diseases with EMD received chimeric antigen receptor (CAR)-T treatment combined with pomalidomide, and CAR-T cells were treated with pomalidomide in vitro to determine its killing activity and cytokine secretion. Three patients with RRMM were given B cell maturation antigen (BCMA)-CAR-T therapy. All 3 patients with B-cell leukemia/lymphoma received CD19/22-CAR-T sequential infusion. There were no treatment-related deaths. The maximum overall response rate (ORR) was 100%. Median follow-up was 211.5 days (75-407 days). Three patients (50%) experienced cytokine release syndrome, all of which were grade 1, and no neurotoxicity was observed. In vitro experiments showed that the killing activity did not differ significantly between BCMA-CAR-T cells with and without pomalidomide (10, 25, or 50 μg/mL) in 8226/U266 cell cocultures (P > .05). Tumor necrosis factor (TNF)-α and interferon (IFN)-γ secretion was significantly higher from 8226 and Raji cells cocultured with BCMA-CAR-T and cluster of differentiation (CD)19-CAR-T cells (P < .05). Based on the cocultures, adding pomalidomide significantly promoted IFN-γ and TNF-α secretion (P < .05). Based on the above clinical and in vitro studies demonstrating the co-administration of pomalidomide with CAR-T cell treatment demonstrated favorable tolerability and therapeutic effectiveness in RRMM or B-cell leukemia/lymphoma.

Isolated Progression of Multiple Myeloma into the Extramedullary Plasmacytoma of Dura Mater: A Case Report and Review of the Literature

Multiple myeloma (MM) is a disease caused by the uncontrolled proliferation of clonal plasma cells in bone marrow. Extramedullary plasma cell infiltrations may occur at the time of diagnosis but usually arise during systemic disease progression. Central nervous system (CNS) plasmacytomas are extremely rare (less than 1% of patients with MM) and usually occur as a result of systemic disease progression. The frequency of extramedullary progression to CNS without simultaneous systemic progression is not known. Here, we present a challenging case in which local disease progression to CNS occurred without any signs of systemic progression. The extramedullary plasmacytoma originated from the dura mater of the brain mimicking a brain tumor. We review and discuss further treatment options that are available in such rare clinical scenarios in relation to the treatment already undertaken.

Isolated relapse of plasma cell leukemia in the central nervous systems: a case report and literature review

Plasma cell leukemia is a rare yet aggressive form of multiple myeloma characterized by high levels of plasma cells circulating in the peripheral blood. We recently experienced a case of plasma cell leukemia that had been in stringent complete remission for nine years after autologous stem cell transplantations with subsequent courses of lenalidomide maintenance therapy, and then relapsed as an extramedullary plasmacytoma in the central nervous system. Assessment of the bone marrow did not prove proliferation of plasma cells at relapse, but imbalanced elevation of serum levels of free light chains was observed without changes in other clinical biomarkers including immunoglobulin levels. Salvage chemotherapy with isatuximab, pomalidomide, and dexamethasone (IsaPD) was promptly initiated. After two courses of IsaPD, significant remission was achieved and the neuronal symptoms completely resolved. When excessive serum levels of clonotypic free light chains are noted, their significance should be carefully assessed even when plasma cell propagation in the bone marrow is not observed. In such cases, hematologists should search for extramedullary proliferation of plasma cells, including in the immune-privileged central nervous system.

Case reports: Central nervous system involvement in patients with newly diagnosed multiple myeloma

Multiple myeloma with central nervous system involvement (CNS-MM) is rare, having a poor outcome and occurring in newly diagnosed or relapsed/refractory patients. The current report concerns 3 cases of newly diagnosed MM patients who presented with skull-derived plasmacytomas. Case 1 was a 54-year-old female patient with immunoglobulin D (IgD) subtype who developed extramedullary lesions from the sphenoid and occipital bones and the sphenoid sinus. Cases 2 and 3 had IgA subtype with left or bilateral frontal area lesions. Case 1 was treated with bortezomib, cyclophosphamide and dexamethasone (VCD) as the initial chemotherapy regimen and with bortezomib, lenalidomide, pegylated liposomal doxorubicin and dexamethasone (DVD-R) as the second line regimen. Whole-brain irradiation and intrathecal injection were given but the patient died within 9 months due to disease progression. Case 2 was treated with bortezomib, lenalidomide and dexamethasone (VRD) and received autologous hematopoietic stem cell transplantation (auto-HSCT) with a conditioning regimen of cyclophosphamide, etoposide and melphalan (CEM). Case 3 received DVD-R initially and auto-HSCT with a conditioning regimen of busulfan, cyclophosphamide, and etoposide (BuCyE). Cases 2 and 3 survived until the last follow-up more than 3 years later. Auto-HSCT with modified conditioning regimen as consolidation therapy improved the prognosis of CNS-MM.

Multiple myeloma with isolated central nervous system relapse after autologous stem cell transplantation: A case report and review of the literature

Patients with multiple myeloma (MM) rarely present with central nervous system (CNS) involvement as a manifestation of extramedullary disease (EMD), a condition that is associated with poor prognosis. CNS relapse without evidence of systemic involvement is even rarer, and there is no standardized treatment because there are only few case reports. We present a 47-year-old female who was diagnosed with nonsecretory multiple myeloma (NSMM) 9 years previously. She had a complete remission after receiving aggressive therapies, including high-dose chemotherapy and autologous stem cell transplantation (ASCT). However, after 7 years of progression-free survival, she had CNS relapse without evidence of systemic involvement. We switched to a salvage regimen consisting of high-dose methotrexate with lenalidomide. She achieved rapid clinical improvement, with a reduction in cerebrospinal fluid plasmacytosis of more than 80%, and no notable side effects. Our description of this unique case of a patient with MM and isolated CNS relapse after ASCT provides a reference for physicians to provide more appropriate management of these patients. We also reviewed previously reported cases and summarized the outcomes of isolated CNS relapse after ASCT, and discuss the pathogenesis and possible treatment strategies for MM with isolated CNS relapse.

A Case Report of Leptomeningeal Myelomatosis and Rapid Improvement with Regimen Consisting of Daratumumab, Pomalidomide, Vincristine, Procarbazine, and Dexamethasone

Central nervous system (CNS) involvement in multiple myeloma (MM) (MM-CNS) in the form of leptomeningeal myelomatosis or brain parenchyma plasmacytoma is rare, causing challenges in clinical diagnosis and treatment. We would like to report a case of leptomeningeal myelomatosis and illustrated the challeges. A 61-year-old man was diagnosed with MM with left paravertebral plasmacytoma, R-ISS II with high suspicion of double-hit MM, either biallelic aberrancy of TP53 or del(17p) and IGH aberrancy depending on the definition chosen, treated with lenalidomide-bortezomib-dexamethasone and local radiotherapy, later developed systemic relapse and progression to MM-CNS in the form of leptomeningeal myelomatosis. A modified CNS-based treatment not reported before, consisting of daratumumab, pomalidomide, vincristine, procarbazine, and dexamethasone, brought a rapid clinical improvement and warrants a further study. Incorporation of intrathecal thiotepa into the regimen would likely increase the efficacy.

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

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

Research progress on treatment of extramedullary multiple myeloma

ABSTRACTObjectives: Extramedullary multiple myeloma (EMM) is a relatively less frequent subentity of multiple myeloma (MM) and is generally considered to be a poor prognostic factor. Novel agents and hematopoietic stem cell transplantation (HSCT) have led to a significant improvement in the progression-free survival and overall survival of patients with MM, but outcomes of EMM remain dismal. Little is known regarding the role of novel therapies in this setting. This review summarizes the current available data regarding the roles of proteasome inhibitors, immunomodulators, monoclonal antibodies, chimeric antigen receptor (CAR)-T cell therapy and HSCT in EMM.Methods: A systematic literature review through PubMed was conducted to summarize the published evidence on the therapeutic developments of novel agents and HSCT in EMM. Literature sources published in English were searched, using the terms multiple myeloma, extramedullary and treatment.Results: Long-term outcomes of EMM patients remain dismal despite the utilization of novel agents and HSCT. The standard therapy of EMM has not been established. EMM should be managed as high-risk disease and treated accordingly.Discussion and conclusion: This review will provide an insight on the current and emerging treatment strategies as well as their efficacy in EMM. Further subgroup analyses in large prospective trials focusing on EMM is needed to help optimize the therapy.

A Rare Case of Epidural Myeloma Presenting as Recurrent Subdural Bleeding

Multiple myeloma (MM) is an incurable clonal B-cell malignancy that usually presents with neoplastic monoclonal plasma cells in either bone or soft tissues. Central nervous system involvement of the myeloma (CNS-MM), such as dural myeloma or intraparenchymal infiltration, or diffuse leptomeningeal involvement, is uncommon. Dural involvement of myeloma without parenchymal or leptomeningeal disease is even rarer, with only seven cases reported previously. We present a case of epidural myeloma in a 50-year-old man with known kappa light chain MM, presenting with multiple episodes of subdural hemorrhage and progressive neurological deficits. He initially presented with severe back pain, hypercalcemia, and acute kidney injury (AKI). Further evaluation showed lytic bone lesions and elevated kappa light chains, and bone marrow biopsy showed 32% of clonal plasma cells. He was initially treated with bortezomib, lenalidomide, and dexamethasone combination, followed by pomalidomide and daratumumab. Eventually, he developed two episodes of subdural hemorrhage and left-sided seventh cranial nerve palsy, which was treated conservatively and monitored by computed tomography (CT) of the head. However, he gradually developed multiple cranial nerve palsies, weakness, and urinary incontinence. Cerebrospinal fluid (CSF) analysis showed elevated protein without any aberrant immunophenotype. Magnetic resonance imaging (MRI) of the brain showed diffuse smooth dural enhancement with extensive calvarial and skull base marrow replacement; MRI of the spine showed diffuse epidural enhancement in thoracic and lumbar regions, findings consistent with epidural myeloma. The patient received three doses of cranial irradiation but, unfortunately, could not tolerate further treatment and opted for hospice care. Intracranial hemorrhage is common in MM patients, and it is important to consider CNS involvement in patients presenting with recurrent subdural hemorrhage and to perform imaging (preferably MRI) earlier in the disease course. Due to its rarity, the treatment of CNS-MM is very heterogeneous. Thus, case reporting is important to accumulate data on this rare presentation.

Recurrent or progressive pediatric brain tumors: population pharmacokinetics and exposure-response analysis of pomalidomide

BACKGROUND

Pomalidomide, an immunomodulatory drug, was investigated for pediatric brain tumors. The objectives of this analysis were to characterize the PK of pomalidomide and to examine exposure-response relationship in pediatric patients with recurrent or progressive primary brain tumors.

METHODS

Nonlinear mixed effects modeling was employed in developing a population PK model of pomalidomide using a total of 343 concentrations from 70 patients. Logistic regression models were used for exposure-response analyses.

RESULTS

The PK of pomalidomide was adequately described with a one compartment model with first-order absorption and elimination. Body surface area (BSA) was identified as a statistically significant covariate of apparent clearance and volume of distribution; however, the impact of BSA on exposure parameters was not deemed clinically relevant. Pomalidomide exposure was not associated with higher probabilities of treatment-emergent adverse events or pomalidomide dose interruptions during Cycle 1. Covariates such as BSA, weight, sex, age, and race had no significant effect on safety endpoints. The PK of pomalidomide in pediatric patients with brain tumors was generally consistent with that in adult patients with multiple myeloma after adjustment for BSA.

CONCLUSIONS

This is the first study to characterize PK of pomalidomide in pediatric patients, which supports BSA-based dosing for pediatric patients.

IMPACT

This is the first study to characterize PK of pomalidomide in pediatric patients, which supports BSA-based dosing for pediatric patients. There is no significant pomalidomide PK difference between adults and pediatrics. Pomalidomide exposure was not associated with higher probabilities of treatment-emergent adverse event or pomalidomide dose interruptions during Cycle 1.

Isolated third cranial nerve palsy as the first presentation of multiple myeloma

A 50-year-old woman presented with a right-sided isolated third cranial nerve palsy. MRI brain showed a mass lesion arising from the right clivus with extension into the cavernous sinus. Blood investigations and bone marrow biopsy were suggestive of multiple myeloma with hypercalcaemia and renal dysfunction. It was unclear at first if the intracranial lesion was due to myelomatous involvement or a separate disease entirely. The patient declined consent for a biopsy and cerebrospinal fluid analysis was inconclusive. She was treated with bortezomib based chemotherapy and the palsy resolved by day 6, which helped clinch the rare diagnosis of central nervous system (CNS) involvement by multiple myeloma. Most patients with CNS myeloma have a dismal survival of under 6 months but she is on therapy for relapse 26 months after diagnosis. While placed under the umbrella of CNS myeloma, patients with osteodural myeloma have better outcomes, perhaps due to their distinct aetiopathogenesis.

Phase 1 study of pomalidomide in children with recurrent, refractory, and progressive central nervous system tumors: A Pediatric Brain Tumor Consortium trial

BACKGROUND

Central nervous system (CNS) malignancies are the most common solid tumors among children, and novel therapies are needed to help improve survival. Pomalidomide is an immunomodulatory agent that displays antiangiogenic and cytotoxic activity, making it an appropriate candidate to explore in pediatric CNS tumors.

METHODS

A phase 1 first in pediatric trial of pomalidomide was conducted in children with recurrent, progressive, and refractory CNS tumors. The primary objective was to determine the maximum tolerated dose (MTD) and/or recommended phase 2 dose (RP2D) when given orally once daily for 21 consecutive days of a 28-day cycle. Once the MTD was established, 12 additional patients were enrolled on expansion cohorts based on age and steroid use.

RESULTS

Twenty-nine children were enrolled and 25 were evaluable for dose-limiting toxicity (DLT). The MTD was 2.6 mg/m² (dose level 2). Four DLTs were observed in three patients at dose level 3 (3.4 mg/m² ) includeding grade 3 diarrhea, grade 3 thrombocytopenia, grade 3 lung infection, and grade 4 neutropenia. The most common adverse events were grade 1 and 2 myelosuppression. One patient with an oligodendroglioma had stable disease for nine cycles, and a second patient with an anaplastic pleomorphic xanthoastrocytoma achieved a sustained partial response. Immunologic analyses suggested that pomalidomide triggers immunomodulation.

CONCLUSIONS

The MTD of pomalidomide is 2.6 mg/m² . It was well tolerated, and immune correlates showed a serum immune response. These data led to an industry-sponsored phase 2 trial of pomalidomide monotherapy in children with recurrent brain tumors (NCT03257631).

Multiple Myeloma with Central Nervous System Relapse Early after Autologous Stem Cell Transplantation: A Case Report and Literature Review

Few reports have so far described central nervous system (CNS) involvement in multiple myeloma (MM), which shows a poor prognosis owing to its resistance to several treatments. We herein describe a 45-year-old woman who had MM (diagnosed with IgA-κ type) with CNS relapse early after undergoing autologous hematopoietic stem cell transplantation. Because no standard treatment for CNS lesions of MM has been established, we conducted a literature review on the cerebrospinal fluid (CSF) transferability of drugs for MM, since it was considered to be a useful tool for CNS involvement. Immunomodulatory-drugs including pomalidomide exhibit a good CSF transfer ability, and, therefore, may be beneficial against the CNS involvement of MM.

Multiple myeloma with central nervous system relapse

Central nervous system involvement in multiple myeloma is a rare complication but carries a very poor prognosis. We provide a review of current literature, including presentation, treatment and survival data, and describe our experience in a regional hematologic malignancy diagnosis center where, over a 15-year period, ten cases were identified. Although the median age of onset, frequently between 50-60 years, is comparatively young, those diagnosed usually have a preceding diagnosis of multiple myeloma and often have had several lines of treatment. We discuss putative underlying factors such as prior treatment and associations including possible risk factors and features suggestive of a distinct biology. Central nervous system involvement may be challenging to diagnose in myeloma, displaying heterogeneous symptoms that can be confounded by neurological symptoms caused by the typical features of myeloma or treatment side-effects. We discuss the clinical features, imaging and laboratory methods used in diagnosis, and highlight the importance of considering this rare complication when neurological symptoms occur at presentation or, more commonly, during the disease pathway. In the absence of clinical trial data to inform an evidence-based approach to treatment, we discuss current and novel treatment options. Finally, we propose the establishment of an International Registry of such cases as the best way to collect and subsequently disseminate presentation, diagnostic and treatment outcome data on this rare complication of multiple myeloma.

Aggressive Central Nervous System Relapse after Autologous Stem Cell Transplant in Multiple Myeloma: Case Reports and Literature Review

Extramedullary disease is an aggressive presentation at diagnosis and relapse for multiple myeloma (MM) patients. Central nervous system (CNS) is a very rare manifestation of the extramedullary disease, accounting for less than 1% of MM on diagnosis and relapse. Neurological symptoms are unspecific and usually attributed to other causes. We present two patients with CNS-MM at relapse after autologous stem cell transplant highlighting the importance of clinical suspicion and interdisciplinarity at diagnostic workup as well as the need for intensive therapeutic options on such rare and aggressive cases. The presence of neurological abnormalities in anamnesis and physical examination on a patient with MM should always prompt to suspect of a CNS involvement, and active investigation must be undertaken. MRI is the standard radiological method to detect CNS-MM, with histopathological corroboration by stereotactic biopsy and CSF evaluation alongside. Treatment of CNS-MM should include two essential approaches—be able to cross the BBB and treat the systemic disease. There is no standard therapy for this extramedullary relapse, and a tailored and multiple therapy should be promptly started—intrathecal therapy, radiotherapy, and systemic therapy, including an immunomodulator.

Proptosis and hemiplegia as an initial manifestation of multiple myeloma

Multiple myeloma (MM) is a monoclonal gammopathy, also known as the malignant proliferation of plasma cells, presenting with typical complications such as hypercalcemia, osteolytic bone lesions, anemia, renal insufficiency, and frequent infections. Central nervous system (CNS) involvement in MM in the form of parenchymal involvement is very uncommon and has been reported only in 1% of patients. CNS involvement as an initial presentation is very rare and has poor prognosis. Also specific treatment guidelines do not exist for the treatment of such patients. We present here a case of a 40-year-old female patient, with complaints of headache and left eye proptosis followed by left-sided hemiparesis, who after complete workup was diagnosed as a de novo case of stage III extramedullary MM with CNS involvement. Patient was treated with whole brain radiation followed by BCD regimen (injection of bortezomib, injection of cyclophosphamide, and tablet dexamethasone). After three cycles of chemotherapy, patient succumbed in view of consolidation and renal failure.

Successful treatment with pomalidomide and intrathecal injections for central nervous system plasmacytoma in a patient under haemodialysis

WHAT IS KNOWN AND OBJECTIVES

The involvement of the central nervous system (CNS) in multiple myeloma (MM) is uncommon and has an extremely poor prognosis, and optimal treatment strategies for the CNS MM patients have not yet been established.

CASE SUMMARY

A 71-year-old MM patient with severe renal impairment exhibited extramedullary relapse in the CNS and progression while being treated with lenalidomide and dexamethasone. However, she achieved very good partial remission after a treatment with pomalidomide, cyclophosphamide and dexamethasone (PCD) in combination with intrathecal chemotherapy.

WHAT IS NEW AND CONCLUSION

This is the first case report to describe MM with CNS involvement in a patient who had responded to PCD under haemodialysis. The combined intrathecal administration of cytotoxic agents and PCD may prolong survival and is tolerated well by patients with severe renal impairment.

A rare case of multiple myeloma with intracranial extramedullary relapse: One or more myeloma clones?

In a minority of relapsed myeloma, patient's disease may spread into extramedullary sites, associated with high degrees of heterogeneity. The breadth of myeloma therapeutic armamentarium allows clinicians to manage its heterogeneous presentation, including intracranial relapses, with fair success resulting in a significant prolongation of survival.

Multiple myeloma with dural mater involvement

Multiple myeloma is an incurable clonal B-cell malignancy which may present with neoplastic monoclonal plasma cells in either bone or soft tissues. Central nervous system (CNS) involvement such as dural myeloma or intraparenchymal infiltration, or with diffuse leptomeningeal involvement, is uncommon. Dural involvement of myeloma without parenchymal or leptomeningeal disease is an even rarer occurrence; therefore there are no established treatment guidelines for CNS myelomatosis. Here we reported a refractory MM patient progressed to dura mater involvement after the induction therapy but showed good response to lenalidomide treatment.

Dysphagia as an Unusual Presentation of Myeloma

Multiple myeloma is a plasma cell dyscrasis characterized by mature B cells proliferation in the bone marrow. In rare cases, the disease can present as an extramedullary location, making diagnosis and management more challenging. Here, we describe a rare case of tongue extramedullary myeloma and discuss diagnostic, prognostic, and therapeutic issues.

Clinical features, radiological profiles, and surgical outcomes of primary intracranial solitary plasmacytomas: a report of 17 cases and a pooled analysis of individual patient data

PURPOSE

We aim to delineate the clinical characteristics of patients with primary intracranial solitary plasmacytoma (PISPC) and prognostic factors for their outcomes.

METHODS

This study retrospectively reviewed 17 patients with PISPC from our center and an additional 70 cases of PISPC published previously to analyze outcome predictors.

RESULTS

The entire cohort included 38 (43.7%) males and 49 (56.3%) females with a mean age of 54 years. Skull base tumors were found in 49 (56.3%) patients. Gross total resection (GTR) was achieved in 31 (35.6%) patients. Postoperative adjuvant treatments, including radiotherapy (RT) alone, chemotherapy (CMT) alone, and RT + CMT were administered in 49 (56.3%) patients, 3 (3.5%) patients, and 16 (18.4%) patients, respectively. After a median follow-up of 24 (mean 42.4) months, the 5-year disease progression-free survival (PFS), recurrence-free survival (RFS), multiple myeloma (MM)-free survival (MMFS), and overall survival (OS) were 52.9%, 76.2%, 69.6%, and 76.1%, respectively. Multivariate analysis unveiled that a skull base tumor location (HR 2.395, p = 0.040) and no RT (HR 3.115, p = 0.004) were negative prognostic factors for PFS, no RT (HR 10.526, p = 0.003) for RFS, each 1-year increase in age (HR 1.039, p = 0.049) for MMFS, and increasing age (HR 1.052, p = 0.043) and CMT (HR 6.022, p = 0.005) were risk factors for OS. However, GTR did not benefit the aforementioned outcomes.

CONCLUSION

For patients with presumed PISPC, a biopsy followed by RT is recommended for skull base PISPC. However, the role of CMT is still not clear. Our findings need to be verified in a larger prospective cohort in the future. Systematic review registration number CRD42018098782.

Successful eradication of leptomeningeal plasma cell disease

Plasma cell leukaemia (PCL) is a rare and aggressive form of malignant monoclonal gammopathy characterized by the presence of high levels of plasma cells in peripheral blood. Central nervous system involvement of PCL has no established treatment and an extremely poor prognosis. We here present a 59-year-old male patient diagnosed with PCL, initially treated with induction chemotherapy followed by autologous peripheral blood hematopoietic stem cell transplantation. After achieving a partial response, he relapsed and presented with leptomeningeal disease. He was then successfully treated with dexamethasone, pomalidomide, and an intrathecal combination of methotrexate, methylprednisolone and cytarabine. This cleared his cerebrospinal fluid from plasma cells achieving a durable partial response.

Multiple Myeloma of the Central Nervous System: 13 Cases and Review of the Literature

Central nervous system involvement is a rare complication of multiple myeloma with extremely poor prognosis as it usually fails to respond to therapy. We present 13 cases diagnosed at two centers in Budapest and review the current literature. The majority of our cases presented with high-risk features initially; two had plasma cell leukemia. Repeated genetic tests showed clonal evolution in 3 cases. Treatments varied according to the era, and efficacy was poor as generally reported in the literature. Only one patient is currently alive, with 3-month follow-up, and the patient responded to daratumumab-based treatment. Recent case reports show promising effectivity of pomalidomide and marizomib.

Successful Intrathecal Chemotherapy Combined with Radiotherapy Followed by Pomalidomide and Low-Dose Dexamethasone Maintenance Therapy for a Primary Plasma Cell Leukemia Patient

Primary plasma cell leukemia (PPCL) is a rare aggressive variant of plasma cell disorder and frequently presents with extramedullary disease. Central nervous system (CNS) involvement with PPCL has an extremely poor prognosis. We describe a 46-year-old man with PPCL treated with a combination of lenalidomide, bortezomib, and dexamethasone as induction therapy following upfront allogeneic stem cell transplantation (allo-SCT). Despite achieving a very good partial response, the patient suffered from an isolated CNS relapse 12 months after allo-SCT. He was immediately started on concurrent intrathecal chemotherapy (IT) and cranial irradiation (RT). Subsequently, pomalidomide and low-dose dexamethasone (Pd) were given as maintenance therapy. He has been without CNS recurrence for more than 18 months. Our case suggests that concurrent IT and RT followed by Pd maintenance therapy may be an effective option to control CNS relapse of PPCL after allo-SCT.

Bortezomib-related neuropathy may mask CNS relapse in multiple myeloma: A call for diligence

Background: Neuropathy is a common adverse effect of bortezomib. Isolated central nervous system (CNS) relapse in MM remains exceedingly rare and carries a dismal prognosis. We present an unusual case of bortezomib related neuropathy masking a CNS relapse of MM. Case presentation: A 57-year-old female was diagnosed with standard-risk MM with clinical and cytogenetic features not typically associated with CNS involvement. She was treated with 4 cycles of bortezomib/cyclophosphamide/dexamethasone (VCD) and achieved a VGPR, after which she underwent an autologous stem cell transplant (ASCT) followed by bortezomib maintenance. Six months after ASCT she developed symptoms suggestive of peripheral neuropathy which was attributed to bortezomib. However the symptoms persisted despite discontinuation of bortezomib. Imaging and cerebrospinal fluid analysis subsequently confirmed a CNS relapse. Discussion: CNS involvement in MM (CNS-MM) is uncommon and is considered an aggressive disease. Recently published literature has reported biomarkers with prognostic potential. However, isolated CNS relapse is even less common; an event which carries a very poor prognosis. Given the heterogeneous neurologic manifestations associated with MM, clinical suspicion may be masked by confounding factors such as bortezomib-based therapy. The disease may further remain incognito if the patient does not exhibit any of the high risk features and biomarkers associated with CNS involvement. Conclusion: In the era of proteasome inhibitor (PtdIns)/immunomodulator (IMID)-based therapy for MM which carries neurologic adverse effects, it is prudent to consider CNS relapse early. This case further highlights the need for more robust biomarkers to predict CNS relapse and use of newer novel agents which demonstrate potential for CNS penetration.

Central nervous system involvement by multiple myeloma: A multi-institutional retrospective study of 172 patients in daily clinical practice

The multicenter retrospective study conducted in 38 centers from 20 countries including 172 adult patients with CNS MM aimed to describe the clinical and pathological characteristics and outcomes of patients with multiple myeloma (MM) involving the central nervous system (CNS). Univariate and multivariate analyses were performed to identify prognostic factors for survival. The median time from MM diagnosis to CNS MM diagnosis was 3 years. Thirty-eight patients (22%) were diagnosed with CNS involvement at the time of initial MM diagnosis and 134 (78%) at relapse/progression. Upon diagnosis of CNS MM, 97% patients received initial therapy for CNS disease, of which 76% received systemic therapy, 36% radiotherapy and 32% intrathecal therapy. After a median follow-up of 3.5 years, the median overall survival (OS) from the onset of CNS involvement for the entire group was 7 months. Untreated and treated patients had median OS of 2 and 8 months, respectively (P < 0.001). At least one previous line of therapy for MM before the diagnosis of CNS disease and >1 cytogenetic abnormality detected by FISH were independently associated with worse OS. The median OS for patients with 0, 1 and 2 of these risk factors were 25 months, 5.5 months and 2 months, respectively (P < 0.001). Neurological manifestations, not considered chemotherapy-related, observed at any time after initial diagnosis of MM should raise a suspicion of CNS involvement. Although prognosis is generally poor, the survival of previously untreated patients and patients with favorable cytogenetic profile might be prolonged due to systemic treatment and/or radiotherapy. Am. J. Hematol. 91:575-580, 2016. © 2016 Wiley Periodicals, Inc.

How I treat extramedullary myeloma

Extramedullary myeloma (EMM) is defined by the presence of plasma cells (PCs) outside the bone marrow in a patient with multiple myeloma (MM). Using sensitive imaging techniques including magnetic resonance imaging and positron emission tomography/computed tomography, EMM may be found in up to 30% of MM patients across the overall disease course. The molecular mechanisms underlying the hematogenous spread of PCs outside the bone marrow are only partially known and involve hypoxia and an altered expression of adhesion molecules. Extramedullary disease is associated with adverse prognostic factors (ie, high lactate dehydrogenase level, 17p deletion, and high-risk gene expression profile). The prognosis of EMM is poor, and the median overall survival of patients who experience an extramedullary relapse is <6 months. The adverse prognosis is less pronounced in patients with bone-related plasmacytomas than in those with hematogenous EMM. EMM patients should be considered as having high-risk myeloma and treated accordingly. However, EMM clinical situations are extraordinarily heterogeneous, and their management is particularly challenging. In the present review, a case-and-comment format is used to describe our approach to the management of EMM.

MRI negative meningeal myeloma with abducens nerve palsies responding to intrathecal chemotherapy

Meningeal involvement of multiple myeloma is rare. A patient with multiple myeloma presented with bilateral abducens nerve palsies. In the MRI neither lytic skull lesions nor meningeal enhancement could be found. The diagnosis was based on CSF studies and cytology. A neurologic remission was achieved with intrathecal chemotherapy.

Pomalidomide for the treatment of relapsed-refractory multiple myeloma: a review of biological and clinical data

Despite the improvements thanks to the introduction of proteasome inhibitors and immunomodulatory drugs (IMiDs), nearly all myeloma patients eventually become refractory to these drugs. Consequently, the outcome of these patients is very poor. Pomalidomide is a new IMiD with a similar structure to the commonly used IMiD thalidomide and lenalidomide. Pomalidomide exhibited more potent anti-myeloma activity and a similar favorable safety profile compared with thalidomide and lenalidomide. In Phase I-II studies pomalidomide plus low-dose dexamethasone demonstrated activity in myeloma patients refractory to both bortezomib and IMiDs. Based on the results of a Phase III trial, the FDA and EMA agencies granted accelerated approval to pomalidomide, which is now considered a new effective strategy for relapsed and/or refractory myeloma patients. Very promising results were obtained when pomalidomide-dexamethasone was used in combination with other compounds. This review provides updated information about pharmacokinetics, mechanism of action, resistance, clinical efficacy and safety of pomalidomide.

Sensitive liquid chromatography/mass spectrometry methods for quantification of pomalidomide in mouse plasma and brain tissue

Pomalidomide was recently approved by the United States Food and Drug Administration for the treatment of patients with relapsed or refractory multiple myeloma who have received at least two prior therapies. As pomalidomide is increasingly evaluated in other diseases and animal disease models, this paper presents development and validation of a sensitive liquid chromatography tandem mass spectrometry assay for quantification of pomalidomide in mouse plasma and brain tissue to fill a gap in published preclinical pharmacokinetic and analytical data with this agent. After acetonitrile protein precipitation, pomalidomide and internal standard, hesperitin, were separated with reverse phase chromatography on a C-18 column with a gradient mobile phase of water and acetonitrile with 0.1% fomic acid. Positive atmospheric pressure chemical ionization mass spectrometry with selected reaction monitoring mode was applied to achieve 0.3-3000nM (0.082-819.73ng/mL) linear range in mouse plasma and 0.6-6000pmol/g in brain tissue. The within- and between-batch accuracy and precision were less than 15% for both plasma and brain tissue. The method was applied to measure pomalidomide concentrations in plasma and brain tissue in a pilot mouse pharmacokinetic study with an intravenous dose of 0.5mg/kg. This assay can be applied for thorough characterization of pomalidomide pharmacokinetics and tissue distribution in mice.