Immunophenotypic assessment of clonal plasma cells and B-cells in bone marrow and blood in the diagnostic classification of early stage monoclonal gammopathies: an iSTOPMM study

Monoclonal gammopathy of undetermined significance (MGUS) is the earliest discernible stage of multiple myeloma (MM) and Waldenström's macroglobulinemia (WM). Early diagnosis of MG may be compromised by the low-level infiltration, undetectable to low-sensitive methodologies. Here, we investigated the prevalence and immunophenotypic profile of clonal (c) plasma cells (PC) and/or cB-lymphocytes in bone marrow (BM) and blood of subjects with a serum M-component from the iSTOPMM program, using high-sensitive next-generation flow cytometry (NGF), and its utility in the diagnostic classification of early-stage MG. We studied 164 paired BM and blood samples from 82 subjects, focusing the analysis on: 55 MGUS, 12 smoldering MM (SMM) and 8 smoldering WM (SWM). cPC were detected in 84% of the BM samples and cB-lymphocytes in 45%, coexisting in 39% of cases. In 29% of patients, the phenotypic features of cPC and/or cB-lymphocytes allowed a more accurate disease classification, including: 19/55 (35%) MGUS, 1/12 (8%) SMM and 2/8 (25%) SWM. Blood samples were informative in 49% of the BM-positive cases. We demonstrated the utility of NGF for a more accurate diagnostic classification of early-stage MG.

Indolent B-cell lymphoma with t(14;19) investigated from a molecular perspective

T(14;19) is an unusual but distinct genomic alteration reported in low-grade B-cell lymphomas. This structural rearrangement places BCL3 in juxtaposition with IGH inducing proliferation and has been found in chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), marginal zone lymphoma (MZL), and other low-grade B-cell lymphomas. While there are some case series describing this in the context of other cytogenetic alterations, there are limited clinical cases examined from a molecular perspective. We herein describe a case of a low-grade B-cell lymphoma with t(14;19) resulting in IGH::BCL3 fusion on which we performed whole exome sequencing to investigate genetic variants that could contribute to its pathogenesis. We found pathogenic alterations including a variant in CXCR4 which has been shown to be recurrently mutated in different low-grade B-cell lymphomas including lymphoplasmacytic lymphoma (LPL) and MZL. We describe this interesting case in the context of its genomic findings and how it contributes to the literature as a whole.

AA amyloidosis complicating monoclonal gammopathies, an unusual feature validating the concept of "monoclonal gammopathy of inflammatory significance"?

INTRODUCTION

AL amyloidosis is caused by the proliferation of an immunoglobulin-secreting B cell clone. AA amyloidosis is a rare complication of chronic inflammation. However, some patients present with diseases combining monoclonal immunoglobulin production and chronic inflammation. The aim of this work was to describe cases of AA amyloidosis associated with monoclonal gammopathies.

PATIENTS AND METHODS

We reviewed all patients reported in French national amyloid centres presenting with AA amyloidosis and monoclonal gammopathy and performed a literature review. The quality of AA amyloidosis diagnosis and the causal relationship with monoclonal gammopathy were assessed.

RESULTS

In total, four patients from our centres and eight from the literature fulfilled the inclusion criteria. The haematological disorders presenting with monoclonal gammopathy were as follows: Waldenström macroglobulinaemia (n = 8), Schnitzler syndrome (n = 2), multiple myeloma (n = 1) and monoclonal gammopathy of undetermined significance (n = 1). Treatment strategies varied among the cases, with the treatment of the haematological disorder in 4 and anti-inflammatory treatment in 2.

CONCLUSION

Monoclonal gammopathies might be a rare and poorly known cause of AA amyloidosis. Such monoclonal gammopathies could be named "monoclonal gammopathies of inflammatory significance."

Frostbite and Cold Agglutinin Disease: Coexistence of Two Entities Leading to Poor Clinical Outcomes

An 83-year-old woman was admitted to the emergency department for a 7-day history of fatigue and progressive cyanosis in the feet and hands after cold exposure despite physical protective measures. Upon arrival, the patient presented with necrotic cutaneous lesions in both hands and distal lower extremities. Upon admission, hemoglobin was 7.6 g/dL and laboratory tests were consistent with cold agglutinin disease (CAD), the presence of monoclonal IgM, and flow cytometry consistent with lymphoplasmacytic lymphoma, but MYD88 L265P mutation was negative. The patient required blood transfusion, resulting in stabilized hemoglobin and a decrease in markers of hemolysis. Treatment with aspirin 250 mg daily and intravenous iloprost 0.5 mL/h was initiated with a poor clinical response at day 4. Amputation was required. Plasma exchange was performed and chemotherapy with rituximab and bendamustine was initiated. The clinical course was marked by further necrosis, prompting discussions regarding an additional amputation that was not performed considering the high surgical risk and refusal by the patient. Supportive treatment was initiated, and the patient expired one month after hospital admission.

Paraproteinemias and Peripheral Nerve Disease

This article provides an overview of the clinical features, diagnosis, and treatment of the major paraprotein-related peripheral neuropathies, including monoclonal gammopathy of undetermined significance, Waldenström macroglobulinemia, POEMS syndrome, multiple myeloma, transthyretin amyloidosis, and light chain amyloidosis. For each paraprotein neuropathy, the epidemiology, demographics, systemic findings, and electrophysiologic features are presented. Pharmacologic treatment of transthyretin amyloid polyneuropathy also is reviewed.

Transformation of IgM-MGUS into Waldenström´s macroglobulinemia in two of six patients treated for Schnitzler´s syndrome

Transformation of IgM-MGUS into Waldenström´s macroglobulinemia in two of six patients treated for Schnitzler´s syndrome Schnitzler´s syndrome is a very rare, adult-onset, apparently acquired autoinflammatory disease. Chronic urticarial rash and symptoms of systemic inflammation including fever, arthralgia and bone pain with the presence of monoclonal immunoglobulin M (IgM), rarely IgG, are among hallmarks of the disease. We performed a retrospective study of 6 patients (5 men, 1 woman) diagnosed with Schnitzler´s syndrome fulfilling the Strasbourg criteria who had been treated at our centre in the University Hospital Brno from 2007 to 2021. Median age at diagnosis was 54 (45-67) years, median follow up was 8 (3-14) years. All 6 patients had IgM κ monoclonal gammopathy, increased CRP and/or erythrocyte sedimentation rate and arthralgia or bone pain, 4 patients suffered from fever, three had leucocytosis 10 × 109/L and lymphadenopathy was found in one patient. 18FDG-PET/CT scan with low-dose total body CT became a part of the initial baseline assessment in 5 patients with suspected Schnitzler´s syndrome, while Na18F-PET/CT was used in one patient to confirm the presence of osteosclerotic leasions as a criterion of the disease. All patients had osteosclerotic or hyperostotic bone lesions detected by low-dose CT examination, with increased 18FDG uptake in illiac and femoral bone marrow. The patient with Na18F-PET/CT scan revealed intensive abnormal tracer uptake with Na18F-PET/CT being more sensitive for detection of osteosclerotic lesions in Schnitzler´s syndrome than 18FDG-PET/CT. All patients were treated with daily subcutaneous anakinra without any adverse events, with excellent clinical results. We observed complete disappearance of urticaria and other symptoms persisting during years of anakinra administration. IgM-MGUS transformed into Waldenström´s macroglobulinemia in two of six patients, but only one patient developed symptoms requiring RBD (Rituximab, Bendamustin, and Dexamethasone) treatment, which induced almost complete remission of the disease. Successful RBD therapy enabled to prolong intervals of maintenance anakinra from 24 to 48 hours with almost complete control of urticarial rash and other symptoms. We suggest close monitoring of patients with Schnitzler´s syndrome to early capture potential transformation into Waldenström´s macroglobulinemia with succesful treatment of both conditions.

Cardiopulmonary Bypass in the Setting of Waldenström's Macroglobulinemia

Waldenström's Macroglobulinemia (WM) is a rare lymphoma caused by the overproduction of immunoglobulin M (IgM). The elevated level of IgM causes serum hyperviscosity, cold agglutinins, and cryoglobulinemia. Anemia is also present because of impaired production of erythrocytes. For these reasons, placing a patient with WM on cardiopulmonary bypass (CPB) requires careful preparation. In this case, the patient was a 73-year-old male with known Waldenström's disease who required coronary artery bypass graft surgery. This report details the perioperative considerations used for successful CPB on a Waldenström's patient. Critical to this case was the use of plasmapheresis before surgery. Temperature management and acid/base status were carefully controlled. A successful coronary revascularization surgery was performed. Many of the Wadenstrom's disease complications expected on CPB failed to materialize.

Disseminated Cryptococcal Osteomyelitis to the Hand in an Immunosuppressed Lymphoma Patient

Fungal osteomyelitis of the hand is rare with limited evidence-based literature to guide diagnosis and management. We report a case of disseminated cryptococcal osteomyelitis in the middle phalanx from a pulmonary fungal infection in a patient with a history of lymphoplasmacytic lymphoma. Although rare, cryptococcosis should be considered in the differential diagnosis of aggressive lytic lesions with bone pain and associated large soft tissue masses, especially in the immunosuppressed host.

[Clinical and biological characteristics of non-IgM lymphoplasmacytic lymphoma]

OBJECTIVE

To observe the clinical and biological characteristics of Non-IgM-secreting lymphoplasmacytic lymphoma (LPL) and draw the differences between non-IgM LPL and Waldenström macroglobulinemia (WM).

METHODS

Records of 13 patients with non-IgM LPL were retrospectively analyzed between January 2000 and December 2013. The cytogenetic aberrations were detected by fluorescence in situ hybridisation (FISH).

RESULTS

In the cohort, 7 males and 6 females with a median age of 63 years (range 43 to 74), two patients were IgA secreting, 6 with IgG secreting and 5 patients without monoclonal globulin. The major complaint at diagnosis included anemia associated symptom (53.8%), mucocutaneous hemorrhage and superficial lymphadenopathy (15.4%). Eight patients had B symptom at diagnosis. All of the 13 patients had bone marrow involvement and anemia, and 10 patients had 2 or 3 lineage cytopenia. In 5 patients with available immunophenotypic data, all expressed CD19, CD20, CD22 and CD25, but missed the expression of CD10, CD103 and CD38. Two cases had CD5 or sIgM positive alone. Another 2 patients were CD23 or CD11c positive and 3 patients were FMC7 positive. Cytogenetic aberrations had been detected by FISH in 7 patients, but only two (28.6%) patients had aberrations with del(6q).

CONCLUSION

The clinical and biological characteristics had no significantly difference between non-IgM LPL and WM.

[How to diagnose a patient precisely as a myeloma patient?--Lots of problems during diagnostic process]

Typical multiple myeloma can be diagnosed precisely through lots of evaluations including the confirmation of the presence of increased clonal myeloma cells in bone marrow accompanied by monoclonal protein, cytopenia, bone diseases and renal disturbance. However, there still exists not a little difficulity during diagnostic process. In this article, representative problems are presented. Among them, the following issues are included; the confirmation or identification of minimal or 'masked' monoclonal proteins in several conditions (eg. myeloma following polyclonal hypergammaglobulinemic conditions), the differential diagnosis between Waldenström macroglobulinemia and IgM multiple myeloma, the differential diagnosis between MGUS with various complications and myeloma, the differential diagnosis of tumors in refractory phase of myeloma (eg. extramedullary plasmacytoma or transition to lympho -proliferative disorders from myeloma), and finally the interpretation of new M-component or oligo-clonal protein band in some periods after stem cell transplantation for myeloma.