Monoclonal Plasma Cells Research Articles

Daratumumab in the Management of Red Cell Aplasia Following Allogeneic Hematopoietic Stem Cell Transplantation.

Pure red cell aplasia (PRCA) is a rare but significant complication following major ABO-incompatible allogeneic hematopoietic stem cell transplantation (HSCT). The persistence of recipient B lymphocytes producing anti-donor isohemagglutinins leads to reticulocytopenia and anemia, often resulting in transfusion dependence. Current treatment options for post-HSCT PRCA are limited and frequently yield suboptimal responses, complicating patient management. Herein, we report three cases of post-HSCT PRCA successfully managed with daratumumab, a monoclonal antibody targeting CD38-expressing plasma cells. All patients demonstrated rapid reticulocyte recovery and transfusion independence after daratumumab treatment, despite prior treatment failures. These findings suggest that daratumumab may provide a more effective therapeutic approach, with a favorable safety profile compared to traditional therapies. Given its demonstrated efficacy and safety, daratumumab warrants consideration as a first-line treatment for post-HSCT PRCA, potentially improving patient quality of life and reducing transfusion-related complications. Further studies should explore optimal dosing and long-term outcomes.

New horizons in our understanding of precursor multiple myeloma and early interception.

Multiple myeloma is an incurable plasma cell malignancy that evolves over decades through the selection and malignant transformation of monoclonal plasma cells. The evolution from precursor states to symptomatic disease is characterized by an increasing complexity of genomic alterations within the plasma cells and a remodelling of the microenvironment towards an immunosuppressive state. Notably, in patients with advanced disease, similar mechanisms of tumour escape and immune dysfunction mediate resistance to modern T cell-based therapies, such as T cell-engaging bispecific antibodies and chimeric antigen receptor (CAR)-T cells. Thus, an increasing number of clinical trials are assessing the efficiency and safety of these therapies in individuals with newly diagnosed multiple myeloma and high-risk smoldering multiple myeloma. In this Review, we summarize the current knowledge about tumour intrinsic and extrinsic processes underlying progression from precursor states to symptomatic myeloma and discuss the rationale for early interception including the use of T cell-redirecting therapies.

The role of interleukin-20 and vascular endothelial growth factor-A biomarkers in the detection of renal impairment in patients with multiple myeloma

ABSTRACT Background Multiple myeloma (MM) is a malignant incurable disease characterized by monoclonal plasma cell increase associated with renal impairment. Evaluation of neutrophil to lymphocyte ratio (NLR), monocyte to lymphocyte ratio (MLR), platelet to lymphocyte ratio (PLR), hemoglobin/red cell distribution width (HB/RDW), interleukin-20 (IL-20), and vascular endothelial growth factor-A (VEGFA) in patients with MM (with or without renal impairment) as prognostic and severity indicators. Research design and methods A cross-sectional study was conducted on sixty MM patients with renal impairment, sixty MM patients without renal impairment, and sixty subjects (control group). Complete blood count, IL-20 immunoassay, and gene expression of IL-20, and VEGFA were evaluated. Results Higher levels of NLR, MLR, and IL-20, moreover lower levels of PLR, HB/RDW, as well as upregulation of IL-20, and VEGFA gene expression were detected in MM patients especially renal impairment. Receiver operating characteristic curves analysis of NLR, MLR, PLR, and IL-20 showed high sensitivity and specificity in the diagnosis of MM and disease stages. Conclusions NLR, MLR, PLR, HB/RDW, IL-20, and VEGFA may be implicated in the inflammatory process of MM and renal impairment pathogenesis. NLR, MLR, and IL-20 can be used as prognostic markers in MM stages.

An Unusual Case of Lymphoplasmacytic Variant of Multiple Myeloma

Abstract Introduction/Objective Multiple myeloma is characterized by unregulated growth of monoclonal plasma cells with overt production of nonfunctional intact immunoglobulins or immunoglobulin chains. Immunohistochemically, the plasma cells are positive for CD138 and CD38, and are rarely positive for CD20 or cyclin D1. CD20 positivity and plasmacytoid morphology in our case pointed towards a lymphoplasmacytic variant of multiple myeloma. The translocation t(11;14) has been detected in this variant, which can explain the positive cyclin D1 immunostaining. The differential diagnosis of this myeloma variant includes lymphoplasmacytic lymphoma. Methods/Case Report We present a case of a 75-year-old female with no significant past medical history who suffered a fall and hesitated to get evaluated until her pain persisted. Initial ER evaluation revealed she had a compression fracture of the T10 and T11 vertebrae with no other abnormality identified. Subsequently, she underwent kyphoplasty, and bone biopsies were performed. The biopsies showed prominent monotonous lymphocytes and some plasmacytoid cell proliferation. Immunostains showed the tumor cells were positive for CD20, Pax-5, Bcl-2, cyclin D1, CD138, and kappa light chain, weakly positive for CD23; and negative for CD5, CD3, CD10, Sox11, and lambda light chain. Based on the morphology and immunoprofile, current findings were considered suggestive of a low-grade B cell lymphoplasmacytic proliferation with cyclin D1 expression. The differential diagnosis includes a lymphoplasmacytic lymphoma or lymphoplasmacytic variant of multiple myeloma. This case was forwarded to a higher-level care facility for consultation and the diagnosis of plasmacytoma, kappa light chain restricted, was rendered. Results (if a Case Study enter NA) NA Conclusion Misdiagnosis of lymphoma can be made in lesions showing classic plasma cells, numerous lymphoplasmacytic cells, and cyclin-D1 positivity on immunohistochemistry if additional testing is not performed. We recommended further testing, including but not limited to bone marrow biopsy, molecular testing, FISH, and genetic testing for a definitive diagnosis.

A-173 Evaluation of Artificial Intelligence (AI)-assisted Flow Cytometry Analysis for Plasma Cell Neoplasms

Abstract Background Flow cytometry plays a critical role in diagnosing hematologic disorders, yet manual analysis is time-consuming and prone to variability. Significant advancements in artificial intelligence (AI) within healthcare have occurred in recent years. Previously, we developed and evaluated an AI-assisted automated system for diagnosing acute leukemia. This study aims to assess the effectiveness of the AI system in diagnosing plasma cell neoplasms. Methods A total of 76 bone marrow samples were analyzed using a panel of antibodies (CD38, CD56, CD138, Kappa, and Lambda) to determine plasma cell percentages and immunophenotype. All samples were used for initial diagnosis of plasma cell neoplasm or therapeutic monitoring. Manual analysis using Kaluza™ software served as the gold standard. The same flow cytometry data was processed by the AI software (DeepFlow™) for comparison. Pearson correlation coefficients were used to compare AI and manual analysis for diagnosis and plasma cell count. Results Among the 76 cases, manual analysis identified 57 positive cases for monoclonal plasma cells (36 cases of CD38+/CD138+/Kappa+ and 21 cases of CD38+/CD138+/Lambda+), with 89% showing aberrant CD56 expression. AI identified 49 monoclonal cases, missing 8 cases with low plasma cell levels (<0.07%) or brighter fluorescence. AI accurately matched 97% of immunophenotypes with manual analysis. Pearson correlation coefficients demonstrated excellent correlation (r=1.0) between manual and AI plasma cell percentages. Furthermore, AI has also enhanced laboratory efficiency, reducing analysis time per case from 10 minutes with manual methods to just 3 minutes with AI analysis. Conclusions This study shows promise for AI-assisted flow software in diagnosing plasma cell neoplasms. AI has enhanced operational efficiency by reducing the manual processing and analysis time. Further training is needed to improve the identification of variations in fluorescence intensity and low plasma cell levels.

Discovery of a highly specific radiolabeled antibody targeting B-cell maturation antigen: Applications in PET imaging of multiple myeloma.

Multiple myeloma (MM) is characterized by the uncontrolled proliferation of monoclonal plasma cells (PC) in the bone marrow (BM). B-cell maturation antigen (BCMA) is predominantly expressed in malignant plasma cells, and associated with the proliferation, survival, and progression of various myeloma cells. Given these important roles, BCMA emerges as an ideal target antigen for MM therapy. However, effective stratification of patients who may benefit from targeted BCMA therapy and real-time monitoring the therapeutic efficacy poses significant clinical challenge. This study aims to develop a BCMA targeted diagnostic modality, and preliminarily explore its potential value in the radio-immunotherapy of MM. Using zirconium-89 (89Zr, t1/2 = 78.4 h) for labeling the BCMA-specific antibody, the BCMA-targeting PET tracer [89Zr]Zr-DFO-BCMAh230430 was prepared. The EC50 values of BCMAh230430 and DFO-BCMAh230430 were determined by ELISA assay. BCMA expression was assessed in four different tumor cell lines (MM.1S, RPMI 8226, BxPC-3, and KYSE520) through Western blot and flow cytometry. In vitro binding affinity was determined by cell uptake studies of [89Zr]Zr-DFO-BCMAh230430 in these tumor cell lines. For in vivo evaluation, PET imaging and ex vivo biodistribution studies were conducted in tumor-bearing mice to evaluate imaging performance and systemic distribution of [89Zr]Zr-DFO-BCMAh230430. Immunochemistry analysis was performed to detect BCMA expression in tumor tissues, confirming the specificity of our probe. Furthermore, we explored the anti-tumor efficacy of Lutetium-177 labeled BCMA antibody, [177Lu]Lu-DTPA-BCMAh230430, in tumor bearing-mice to validate its radioimmunotherapy potential. The radiolabeling of [89Zr]Zr-DFO-BCMAh230430 and [177Lu]Lu-DTPA-BCMAh230430 showed satisfactory radiocharacteristics, with a radiochemical purity exceeding 99%. ELISA assay results revealed closely aligned EC50 values for BCMAh230430 and DFO-BCMAh230430, which are 57 pM and 67 pM, respectively. Western blot and flow cytometry analyses confirmed the highest BCMA expression level. Cell uptake data indicated that MM.1S cells hada total cellular uptake (the sum of internalization and surface binding) of 38.3% ± 1.53% for [89Zr]Zr-DFO-BCMAh230430 at 12 h. PET imaging of [89Zr]Zr-DFO-BCMAh230430 displayed radioactive uptake of 7.71 ± 0.67%ID/g in MM.1S tumors and 4.13 ± 1.21%ID/g in KYSE520 tumors at 168 h post-injection (n = 4) (P < 0.05), consistent with ex vivo biodistribution studies. Immunohistochemical analysis of tumor tissues confirmed higher BCMA expression in MM.1S tumors xenograft compared to KYSE520 tumors. Notably, [177Lu]Lu-DTPA-BCMAh230430 showed some anti-tumor efficacy, evidenced by slowed tumor growth. Furthermore, no significant difference in body weight was observed in MM.1S tumor-bearing mice over 14 days of administration with or without [177Lu]Lu-DTPA-BCMAh230430. Our study has successfully validated the essential role of [89Zr]Zr-DFO-BCMAh230430 in non-invasively monitoring BCMA status in MM tumors, showing favorable tumor uptake and specific binding affinity to MM tumors. Furthermore, our research revealed, as a proof-of-concept, the effectiveness of [177Lu]Lu-DTPA-BCMAh230430 in radioimmunotherapy for MM tumors. In conclusion, we present a novel BCMA antibody-based radiotheranostic modality that holds promise for achieving efficient and precise MM diagnostic and therapy.

A case of paraprotein-negative POEMS syndrome: Case report and literature review.

POEMS syndrome is a rare monoclonal plasma cell disease. The diagnosis of POEMS requires polyradiculoneuropathy and monoclonal plasma proliferating as 2 mandatory criteria, at least 1 of the major criteria (Castleman disease, elevated vascular endothelial growth factor level, and sclerotic bone lesion), and at least 1 of the minor criteria (organomegaly, extravascular volume overload, endocrinopathy, skin changes, papilledema, and thrombocytosis/polycythemia). This multisystem disorder is of high heterogeneity, and few variants of POEMS with no evidence of monoclonal gammopathy have been described, which further complicates the diagnosis in clinical practice. Now, we report a case of paraprotein-negative POEMS syndrome. A 45-year-old woman complained of lower extremity edema, shortness of breath, abdominal distension, and lymphadenopathy for few years. Finally, she was diagnosed with paraprotein-negative POEMS syndrome. With the lenalidomide-based regimen, the symptoms were all relieved. Paraprotein-negative POEMS syndrome. Lenalidomide-based regimen and some supportive therapy. All symptoms were relieved after 1 year of treatment. Physicians should pay more attention to the POEMS syndrome, especially the POEMS syndrome variants, which are absence of paraprotein; probably, these variants are just "on the way" to classic POEMS syndrome antiplasma cell therapy, which remains the treatment of choice.

3D osteocyte lacunar morphometry of human bone biopsies with high resolution microCT: From monoclonal gammopathy to newly diagnosed multiple myeloma

Osteocytes are mechanosensitive, bone-embedded cells which are connected via dendrites in a lacuno-canalicular network and regulate bone resorption and formation balance. Alterations in osteocyte lacunar volume, shape and density have been identified in conditions of aging, osteoporosis and osteolytic bone metastasis, indicating patterns of impaired bone remodeling, osteolysis and disease progression. Osteolytic bone disease is a hallmark of the hematologic malignancy multiple myeloma (MM), in which monoclonal plasma cells in the bone marrow disrupt the bone homeostasis and induce excessive resorption at local and distant sites. Qualitative and quantitative changes in the 3D osteocyte lacunar morphometry have not yet been evaluated in MM, nor in the precursor conditions monoclonal gammopathy of undetermined significance (MGUS) and smoldering multiple myeloma (SMM). In this study, we characterized the osteocyte lacunar morphology in trabecular bone of the iliac crest at the ultrastructural level using high resolution microCT in human bone biopsy samples of three MGUS, two SMM and six newly diagnosed MM. In MGUS, SMM and MM we found a trend for lower lacunar density and a shift towards larger lacunae with disease progression (higher 50 % cutoff of the lacunar volume cumulative distribution) in the small osteocyte lacunae 20–900 μm3 range compared to control samples. In the larger lacunae 900–3000 μm3 range, we detected significantly higher lacunar density and microporosity in the MM group compared to the MGUS/SMM group. Regarding the shape distribution, the MGUS/SMM group showed a trend for flatter, more elongated and anisotropic osteocyte lacunae compared to the control group. Altogether, our findings suggest that osteocytes in human MM bone disease undergo changes in their lacunae density, volume and shape, which could be an indicator for osteolysis and disease progression. Future studies are needed to understand whether alterations of the lacunae architecture affect the mechanoresponsiveness of osteocytes, and ultimately bone adaptation and fracture resistance in MM and its precursors conditions.

Correlation between Morphological Typing and Monoclonality of Bone Marrow Plasma Cells and Its Diagnostic Value for High-Risk Smoldering Multiple Myeloma

To investigate the correlation between morphological typing and monoclonality of bone marrow plasma cells, and explore the diagnostic value of plasma cell morphological typing for high-risk smoldering multiple myeloma(HR-SMM). The correlation between the morphological characteristics and the monoclonality of bone marrow plasma cells was analyzed in 84 patients with HR-SMM who treated in our hospital. The consistency of morphologically abnormal bone marrow plasma cells with serum free light chain (sFLC) ratio, next-generation sequencing (NGS) detection results, and its correlation with monoclonal plasma cells detected by flow cytometry (FCM) were further verified. The immunoglobulin types and levels of non-involved immunoglobulins in serum of the patients were detected, and the distribution of plasma cell clusters in patients with different disease was observed. The mean percentage of mature plasma cells were decreased successively in the order of reactive plasmacytosis (RP) group, monoclonal gammopathy of undetermined significance (MGUS) group, smoldering multiple myeloma (SMM) group, HR-SMM group and multiple myeloma (MM) group; while the mean percentage of immature, primitive, reticular and flaming plasma cells were increased successively in the order of RP group, MGUS group, SMM group, and HR-SMM group, and the difference between any two groups was statistically significant (P < 0.05).The average proportion of abnormal plasma cells in the bone marrow of HR-SMM patients was 96.2% of the total plasma cells. The proportion of abnormal plasma cells were in good agreement with the sFLC ratio and the results of NGS detection in HR-SMM patients (kappa=0.879 and kappa=0.891, both >0.75)，and showed good correlation with the monoclonal plasma cells with immunophenotype of CD45-/CD38+/CD138+/CD56+/CD19-( γ=0.825). The levels of non-involved immunoglobulin in IgG, IgA and IgM type HR-SMM patients were all decreased by more than 25% compared with the normal reference range, and the differences were statistically significant (P < 0.05). There was no significant difference in the distribution ratio of plasma cell clusters among different disease groups (P >0.05). In HR-SMM patients, the immature, primitive, reticular and flaming plasma cells in bone marrow are considered as abnormal plasma cells, and they are correlated with monoclonal plasma cells. The proportion of abnormal plasma cells in total plasma cells of bone marrow and the reduction extent of non-involved immunoglobulin level in patients have certain reference value for the diagnosis of HR-SMM.

Refractory Toothache: A Multiple Myeloma Case Report

We report a case of Multiple Myeloma (MM) with an unusual presentation: pathological mandibular fracture. The patient presented at the Dentist with a toothache and a tooth infection was suspected. After a few appointments without pain relief, a pathological mandibular fracture was diagnosed. Monoclonal plasma cells were identified in the bone biopsy performed. With this case we want to highlight the importance of formulating MM as a differential diagnosis of refractory toothache

Coefficient of variation and texture analysis of 18F-FDG PET/CT images for the prediction of outcome in patients with multiple myeloma

In multiple myeloma (MM) bone marrow infiltration by monoclonal plasma cells can occur in both focal and diffuse manner, making staging and prognosis rather difficult. The aim of our study was to test whether texture analysis of 18 F-2-deoxy-d-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) images can predict survival in MM patients. Forty-six patients underwent 18 F-FDG-PET/CT before treatment. We used an automated contouring program for segmenting the hottest focal lesion (FL) and a lumbar vertebra for assessing diffuse bone marrow involvement (DI). Maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean) and texture features such as Coefficient of variation (CoV), were obtained from 46 FL and 46 DI. After a mean follow-up of 51 months, 24 patients died of myeloma and were compared to the 22 survivors. At univariate analysis, FL SUVmax (p = 0.0453), FL SUVmean (p = 0.0463), FL CoV (p = 0.0211) and DI SUVmax (p = 0.0538) predicted overall survival (OS). At multivariate analysis only FL CoV and DI SUVmax were retained in the model (p = 0.0154). By Kaplan-Meier method and log-rank testing, patients with FL CoV below the cut-off had significantly better OS than those with FL CoV above the cut-off (p = 0.0003), as well as patients with DI SUVmax below the threshold versus those with DI SUVmax above the threshold (p = 0.0006). Combining FL CoV and DI SUVmax by using their respective cut-off values, a statistically significant difference was found between the resulting four survival curves (p = 0.0001). Indeed, patients with both FL CoV and DI SUVmax below their respective cut-off values showed the best prognosis. Conventional and texture parameters derived from 18F-FDG PET/CT analysis can predict survival in MM patients by assessing the heterogeneity and aggressiveness of both focal and diffuse infiltration.

DCE-MRI to distinguish all monoclonal plasma cell disease stages and correlation with diffusion-weighted MRI/PET-based biomarkers in a hybrid simultaneous whole body-2-[18F]FDG-PET/MRI imaging approach

BackgroundDynamic contrast-enhanced-MRI (DCE-MRI) is able to study bone marrow angiogenesis in patients with multiple myeloma (MM) and asymptomatic precursor diseases but its role in the management of MM has not yet been established. The aims of this prospective study was to compare DCE-MRI-based parameters between all monoclonal plasma cell disease stages in order to find out discriminatory parameters and to seek correlations with other diffusion-weighted MRI and positron emission tomography (PET)-based biomarkers in a hybrid simultaneous whole-body-2-[18F]fluorodeoxyglucose (FDG)-PET/MRI (WB-2-[18F]FDG-PET/MRI) imaging approach.MethodsPatients with newly diagnosed Monoclonal gammopathy of undetermined significance (MGUS), smoldering multiple myeloma (SMM) or symptomatic MM according to international myeloma working group and underwent WB-2-[18F]FDG-PET/MRI imaging including bone marrow DCE sequences at the Nantes University Hospital were prospectively enrolled in this study before receiving treatment.ResultsOne hundred and sixty-seven patients (N = 167, mean age: 64 years ± 11 [Standard deviation], 66 males) were considered for the analysis. DCE-MRI-based Peak Enhancement Intensity (PEI), Time to PEI (TPEI) and their maximum intensity time ratio (MITR: PEI/TPEI) values were significantly different between the different monoclonal plasma cell disease stages, PEI values increasing and TPEI values decreasing progressively along the spectrum of plasma cell disorders, from MGUS stage to symptomatic multiple myeloma. PEI values were significantly higher in patients with diffuse bone marrow involvement (either in PET or in MRI images) than in those without diffuse bone marrow involvement, unlike TPEI values. PEI and TPEI values were not significantly different between patients with or without focal bone lesions.ConclusionDifferent DCE-MRI-based parameters (PEI, TPEI, MITR) could significantly differentiate all monoclonal plasma cell disease stages and complemented conventional MRI and PET-based biomarkers.

A Rare Case of Castleman Variant of POEMS Syndrome

Abstract POEMS syndrome is a rare multisystemic disease, characterized by polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, and skin changes. The presence of polyneuropathy and monoclonal plasma cell proliferation is mandatory for the diagnosis of typical POEMS syndrome. However, some patients lack one of the mandatory features and are classified as the variants of POEMS syndrome. A 61-year-old male presented with the clinical picture of progressive numbness in both lower extremities and weakness in all four extremities for a 6-month duration associated with bilateral axillary lymphadenopathies, pedal edema, clubbing, and unintentional weight loss of 15 kg in 6 months. A nerve conduction study showed severe sensorimotor polyneuropathy of demyelinating type in all four extremities. A lymph node biopsy showed Castleman disease, and the computed tomography scan was suggestive of multiple osteosclerotic lesions. A diagnosis of the Castleman variant of POEMS syndrome was made, and the patient was treated with Bortezomib-based therapy with improvement in his symptoms on follow-up at 1 year. Due to the lack of definite treatment guidelines for this disease, the information provided through case reports and case series becomes very important for the treatment of such patients leading to the resolution of polyneuropathy and the maintenance of functionality in patients.

Recent Advances in The Definition of the Molecular Alterations Occurring in Multiple Myeloma.

Multiple myeloma (MM) is a disorder of the monoclonal plasma cells and is the second most common hematologic malignancy. MM initiation and progression are dependent upon complex genomic abnormalities. The current pathogenic model of MM includes two types of primary events, represented by chromosome translocations or chromosome number alterations resulting in hyperdiploidy. These primary molecular events are observed both in MM and in monoclonal gammopathy, its premalignant precursor. Subsequent genetic events allow the progression of monoclonal gammopathy to MM and, together with primary events, contribute to the genetic complexity and heterogeneity of MM. Newer therapies have considerably improved patient outcomes; however, MM remains an incurable disease and most patients experience multiple relapses. The dramatic progresses achieved in the analysis of the heterogeneous molecular features of different MM patients allowed a comprehensive molecular classification of MM and the definition of an individualized prognostic model to predict an individual MM patient's response to different therapeutic options. Despite these progresses, prognostic models fail to identify a significant proportion of patients destined to early relapse. Treatment strategies are increasingly. Based on disease biology, trials are enriched for high-risk MMs, whose careful definition and categorization requires DNA sequencing studies.

Anti-tumor effect of dandelion flavone on multiple myeloma cells and its mechanism

BackgroundMultiple myeloma (MM) is a prevalent hematologic malignancy characterized by the uncontrolled proliferation of monoclonal plasma cells in the bone marrow and excessive monoclonal immunoglobulin production, leading to organ damage. Despite therapeutic advancements, recurrence and drug resistance remain significant challenges.ObjectiveThis study investigates the effects of dandelion flavone (DF) on MM cell proliferation, migration, and invasion, aiming to elucidate the mechanisms involved in MM metastasis and to explore the potential of traditional Chinese medicine in MM therapy.MethodsDF's impact on myeloma cell viability was evaluated using the CCK-8 and colony formation assays. Cell mobility and invasiveness were assessed through wound healing and transwell assays, respectively. RT-PCR was employed to quantify mRNA levels of MMP-2, MMP-9, TIMP-1, and TIMP-2. Apoptotic rates and molecular markers were analyzed via flow cytometry and RT-PCR. The PI3K/AKT signaling pathway was studied using Western blot and ELISA, with IGF-1 and the PI3K inhibitor LY294002 used to validate the findings.ResultsDF demonstrated dose-dependent inhibitory effects on MM cell proliferation, migration, and invasion. It reduced mRNA levels of MMP-2 and MMP-9 while increasing those of TIMP-1 and TIMP-2. Furthermore, DF enhanced the expression of pro-apoptotic proteins and inhibited M2 macrophage polarization by targeting key molecules and enzymes. The anti-myeloma activity of DF was mediated through the inhibition of the PI3K/AKT pathway, as evidenced by diminished phosphorylation and differential effects in the presence of IGF-1 and LY294002.ConclusionBy modulating the PI3K/AKT pathway, DF effectively inhibits MM cell proliferation, migration, and invasion, and induces apoptosis, establishing a novel therapeutic strategy for MM based on traditional Chinese medicine.

POEMS syndrome with undetectable M-protein: a case report and literature review

BackgroundPolyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes (POEMS) syndrome is a rare plasma cell (PC) neoplasm with associated paraneoplastic syndrome. According to the current diagnostic criteria, peripheral polyneuropathy and monoclonal PC proliferative disorder represent two mandatory criteria.Case presentationWe report a 54-year-old male with peripheral neuropathy of bilateral lower limbs, sclerotic bone lesions, elevated vascular endothelial growth factor (VEGF) levels, splenomegaly, extravascular volume overload, endocrinopathy, and skin hemangiomas. Of note, serum and urine protein electrophoresis (PEP) and immunofixation electrophoresis (IFE) of this patient indicated undetectable M-protein and the normal ratio of free light chains κ and λ (FLC-R (κ/λ)). No monoclonal PCs were found in bone marrow examinations or biopsy of diseased bones. However, his clinical manifestations matched most of the diagnostic criteria. After excluding other diseases that are easily confused with POEMS syndrome, the diagnosis of variant POEMS syndrome with undetectable M-protein was proposed. The patient obtained clinically significant improvement and elevated VEGF returned to normal after 6 months of treatment with lenalidomide plus dexamethasone.ConclusionsMonoclonal PC dyscrasia (M-protein) while being a mandatory criterion for POEMS syndrome is undetectable in a considerable amount of patients that otherwise demonstrate typical symptoms. Here, we reported a case of variant POEMS syndrome with featured clinical manifestations, elevated VEGF levels, and good response to therapies targeting PCs but no evidence of M-protein. Therefore, negative results in M-protein and monoclonal PCs aren’t enough to reject the diagnosis of POEMS syndrome. It is imperative to recognize the variant form of POEMS syndrome.

Paraproteinemic neuropathies.

The diagnostic evaluation of a peripheral neuropathy includes testing for the presence of monoclonal gammopathy, which can be found in about 10% of patients with peripheral neuropathy. Our role, as physicians, is to determine whether the neuropathy is directly related to the gammopathy or whether the co-occurrence of these two disorders is purely coincidental. The evaluating physician needs to be familiar with the different types of neuropathies associated with monoclonal gammopathies, their clinical and electrodiagnostic characteristics, and their appropriate diagnostic evaluation and management. Testing for monoclonal protein disorders includes serum protein electrophoresis (SPEP) and immunofixation of blood, and in some cases of urine, as well as measurement of free light chains and quantitative immunoglobulins. Specific antibody testing is directed by paraprotein type and neuropathy phenotype. Patients with abnormal free light chains in association with sensory and autonomic neuropathy should be evaluated for AL amyloidosis. When a lambda monoclonal protein is identified together with a clinical phenotype of chronic inflammatory demyelinating neuropathy (CIDP), a diagnosis of polyneuropathy, organomegaly, endocrinopathy, monoclonal plasma cell disorder, skin changes (POEMS) syndrome should be considered. Patients with IgM paraprotein associated neuropathy should be assessed for distal acquired demyelinating sensorimotor (DADS) neuropathy, with or without anti myelin associated glycoprotein (MAG) antibody or CANOMAD syndrome. In many cases, a monoclonal gammopathy of uncertain significance (MGUS) is incidental and unrelated to the neuropathy. Collaboration with oncology is critical in evaluating patients with monoclonal proteins to assess for underlying plasma cell neoplasms or B cell lymphomas.

#410 Novel renal pathology and treatment of TIN with monoclonal plasma cells invasion in a patient with Sjögren's syndrome and IgA monoclonal gammopathy

Abstract Background and Aims Patients with Sjögren's syndrome (SS) may occasionally present with monoclonal gammopathy of undetermined significance (MGUS), of the rare IgA type. Additionally, they may present with tubulointerstitial nephritis (TIN) infiltrated by polyclonal plasmacytes and lymphocytes. Previous reports indicate the development of IgA-type MGUS and TIN with monoclonal plasma cells in some SS patients, which are considered distinct from monoclonal gammopathy of renal significance (MGRS) because there is no evidence that monoclonal gammopathy affects nephropathy. Although treatment with prednisolone (PSL) has shown beneficial effects, the influence of monoclonal plasma cells on nephropathy remains unclear and a standardized treatment approach is lacking. Here we present a new renal pathological insight through a case of such a patient as described above, who underwent renal biopsy before and after PSL treatment. The aim is to propose a treatment strategy based on the findings of the second renal biopsy. Method and Results (Case Presentation) A 75-year-old Japanese man with primary complaint of dry mouth was diagnosed with SS by lip biopsy and anti-Ro/SSA and La/SSB antibody tests. Monoclonal proteins were found in both blood and urine. After immunoelectrophoresis, bone marrow puncture, and 18F-FDG PET/CT, we identified it as IgA kappa-type MGUS. At the same time, he developed renal dysfunction and was admitted to our hospital (week 1, Fig. 1) for a renal biopsy. The biopsy revealed severe and diffuse TIN infiltrated by lymphocytes with abundant interstitial plasma cell invasion (Fig. 2a). Minimal changes were observed in the glomeruli. Periodic acid–Schiff staining revealed Dutcher bodies in the nucleus of plasma cells. Immunohistochemical staining for immunoglobulins and light chains showed predominantly positive results for IgA and kappa (Fig. 2b). Monoclonality was confirmed by in situ hybridization. The infiltrates were positive for CD 45, CD 79a, and CD 138, partially positive for CD 19 and CD 20, and negative for CD 5, CD 10, and CD 23. Congo-red staining showed no evidence of amyloid. Immunofluorescence and electron microscopy revealed no detectable immunological deposits in the glomeruli and tubules. Mutations in the myeloid differentiation primary response gene 88 were not detected in the kidney. We diagnosed the condition as acute TIN by lymphocytes with IgA kappa-positive monoclonal plasma cells, distinct from MGRS. Considering the lack of evidence from previous reports on the impact of monoclonal plasma cells on nephropathy, we decided to treat the patient primarily for TIN with SS, initiating PSL at 30 mg/day (0.5 mg/kg/day). Renal function improved rapidly with the treatment, allowing for a gradual reduction in the dose of PSL; however, a low dose of PSL (10 mg/day) was required to prevent relapse. As a complication of PSL, the patient eventually developed a lumbar compression fracture, prompting us to evaluate the effect of PSL on renal function by a renal re-biopsy. The re-biopsy revealed significant recovery of TIN by lymphocytes (Fig. 2c). Other findings, including abundant interstitial plasma cells invasion were comparable to the initial biopsy. We diagnosed the condition as recovered TIN by lymphocytes with IgA kappa-positive monoclonal plasma cells. We concluded that TIN by lymphocytes, rather than monoclonal plasma cell invasion, primarily affected the nephropathy, and PSL mainly improved the former. The Nudix hydrolase 15 codon139 in blood was identified as Cys/Cys, indicating a high risk of severe adverse reactions to azathioprine in Asians. Therefore, we decided to concurrently administer mycophenolate mofetil, proven effective in the treatment of TIN with SS. Conclusion In the management patients with SS and IgA monoclonal gammopathy, the focus should be on TIN by lymphocytes rather than monoclonal plasma cell invasion. This case, considering similar cases, suggests that it should be defined as a new disease category. We demonstrate new renal pathology and treatment insights based on renal re-biopsy in a patient treated with PSL.

TAFRO Syndrome on 18F-FDG-PET/CT: An Appealing Diagnostic Tool.

TAFRO syndrome (TS) is a recently recognized and heterogenous systemic disease characterized by a confluence of symptoms: thrombocytopenia (T), anasarca (A), fever (F), reticulin myelofibrosis (R), and organomegaly (O). First described in Japan in 2010, the pathogenesis remains unclear and includes various clinical conditions such as malignancies, rheumatologic disorders, infections, and "Polyneuropathy, Organomegaly, Endocrinopathy, Monoclonal plasma cell disorder, and Skin changes" (POEMS) syndrome. Due to its heterogeneous presentation and potential life-threatening delays in diagnosis, accurate diagnosis is crucial. According to the literature, no specific imaging modality has been recommended for the work-up of patients with suspected TS. Here, we report a case of TS and its management using 18F-FDG-PET/CT imaging as an attractive complementary diagnostic tool.

Reproducible Radiomics Features from Multi-MRI-Scanner Test-Retest-Study: Influence on Performance and Generalizability of Models.

Radiomics models trained on data from one center typically show a decline of performance when applied to data from external centers, hindering their introduction into large-scale clinical practice. Current expert recommendations suggest to use only reproducible radiomics features isolated by multiscanner test-retest experiments, which might help to overcome the problem of limited generalizability to external data. To evaluate the influence of using only a subset of robust radiomics features, defined in a prior in vivo multi-MRI-scanner test-retest-study, on the performance and generalizability of radiomics models. Retrospective. Patients with monoclonal plasma cell disorders. Training set (117 MRIs from center 1); internal test set (42 MRIs from center 1); external test set (143 MRIs from center 2-8). 1.5T and 3.0T; T1-weighted turbo spin echo. The task for the radiomics models was to predict plasma cell infiltration, determined by bone marrow biopsy, noninvasively from MRI. Radiomics machine learning models, including linear regressor, support vector regressor (SVR), and random forest regressor (RFR), were trained on data from center 1, using either all radiomics features, or using only reproducible radiomics features. Models were tested on an internal (center 1) and a multicentric external data set (center 2-8). Pearson correlation coefficient r and mean absolute error (MAE) between predicted and actual plasma cell infiltration. Fisher's z-transformation, Wilcoxon signed-rank test, Wilcoxon rank-sum test; significance level P < 0.05. When using only reproducible features compared with all features, the performance of the SVR on the external test set significantly improved (r = 0.43 vs. r = 0.18 and MAE = 22.6 vs. MAE = 28.2). For the RFR, the performance on the external test set deteriorated when using only reproducible instead of all radiomics features (r = 0.33 vs. r = 0.44, P = 0.29 and MAE = 21.9 vs. MAE = 20.5, P = 0.10). Using only reproducible radiomics features improves the external performance of some, but not all machine learning models, and did not automatically lead to an improvement of the external performance of the overall best radiomics model. Stage 2.