A practical guide to laboratory investigations at diagnosis and follow up in Waldenström macroglobulinaemia: recommendations from the Medical and Scientific Advisory Group, Myeloma Australia, the Pathology Sub-committee of the Lymphoma and Related Diseases Registry and the Australasian Association of Clinical Biochemists Monoclonal Gammopathy Working Group

A Mystery in a Case: Unraveling the Complexity of Bing-Neel Syndrome

Waldenström's macroglobulinemia (WM) is a B-cell non-Hodgkin's lymphoma characterized by clonal IgM-secreting lymphoplasmacytic cell proliferation. Bing-Neel syndrome (BNS) is a rare complication of WM that results in the infiltration of the central nervous system (CNS) with IgM-secreting lymphoplasmacytic cells. This case study presents a 75-year-old Caucasian male with a history of WM and Agent Orange exposure who ultimately was diagnosed with BNS. This patient posed unique diagnostic challenges as the patient experienced clinical symptoms despite the absence of MRI abnormalities and therapeutic challenges.

New developments in the diagnosis and characterization of Waldenström's macroglobulinemia

INTRODUCTION

Waldenström's macroglobulinemia (WM) is defined as a lymphoplasmacytic lymphoma (LPL) with immunoglobulin M (IgM) monoclonal gammopathy and morphologic evidence of bone marrow infiltration by LPL. Immunophenotyping and genotyping provide a firm pathological basis for diagnosis and are particularly valuable in differential diagnosis between WM and related diseases. Emerging technologies in mutational analysis present new opportunities, but challenges remain around standardization of methodologies and reporting of mutational data across centers.

AREAS COVERED

The review provides an overview of the diagnosis of WM, with a particular focus on the role of immunophenotyping and genotyping.

EXPERT OPINION

Demonstration of LPL with a bone marrow biopsy is essential to reach a definitive diagnosis of WM. However, MYD88L265P and a typical WM immunophenotypic profile are valuable for the differential diagnosis of WM and related diseases, such as marginal zone lymphoma, multiple myeloma, and chronic lymphocytic leukemia. These methodologies must be utilized across centers and with appropriate standards followed in the evaluation and reporting of sensitivities and specificities. The diagnostic and/or prognostic value of mutations in genes such as CXCR4 and TP53 that are currently not routinely evaluated in the diagnosis of WM should be explored.

Waldenström macroglobulinemia: 2023 update on diagnosis, risk stratification, and management

DISEASE OVERVIEW

Waldenström macroglobulinemia (WM) is a lymphoplasmacytic lymphoma with immunoglobulin M (IgM) monoclonal protein. Clinical features include anemia, thrombocytopenia, hepatosplenomegaly, lymphadenopathy, and rarely hyperviscosity.

DIAGNOSIS

Presence of IgM monoclonal protein associated with ≥10% clonal lymphoplasmacytic cells in bone marrow confirms the diagnosis. The L265P mutation in MYD88 is detectable in more than 90% of patients and is found in most IgM MGUS patients. MYD88 is not required for the diagnosis.

RISK STRATIFICATION

Age, hemoglobin level, platelet count, β2 microglobulin, LDH, and monoclonal IgM concentrations are characteristics that are predictive of outcomes.

RISK-ADAPTED THERAPY

Not all patients who fulfill WM criteria require therapy; these patients can be observed until symptoms develop. Rituximab-monotherapy is inferior to regimens that combine it with bendamustine, an alkylating agent, a proteosome inhibitor, or a BTK inhibitor. The preferred Mayo Clinic induction is either rituximab and bendamustine (without rituximab maintenance) or zanubrutinib.

MANAGEMENT OF REFRACTORY DISEASE

Bortezomib, cyclophosphamide, fludarabine, thalidomide, everolimus, Bruton Tyrosine Kinase inhibitors, carfilzomib, lenalidomide, bendamustine, and venetoclax have all been shown to have activity in relapsed WM. Given WM's natural history, the reduction of therapy toxicity is an important part of treatment selection.

Diagnostics in Waldenström's macroglobulinemia: a consensus statement of the European Consortium for Waldenström's Macroglobulinemia

The diagnosis of Waldenström's macroglobulinemia (WM), an IgM-associated lymphoplasmacytic lymphoma, can be challenging due to the different forms of disease presentation. Furthermore, in recent years, WM has witnessed remarkable progress on the diagnostic front, as well as a deeper understanding of the disease biology, which has affected clinical practice. This, together with the increasing variety of tools and techniques available, makes it necessary to have a practical guidance for clinicians to perform the initial evaluation of patients with WM. In this paper, we present the consensus recommendations and laboratory requirements for the diagnosis of WM developed by the European Consortium of Waldenström's Macroglobulinemia (ECWM), for both clinical practice as well as the research/academical setting. We provide the procedures for multiparametric flow cytometry, fluorescence in situ hybridization and molecular tests, and with this offer guidance for a standardized diagnostic work-up and methodological workflow of patients with IgM monoclonal gammopathy of uncertain significance, asymptomatic and symptomatic WM.

MYD88 L265P Mutation Detection by ddPCR: Recommendations for Screening and Minimal Residual Disease Monitoring : ddPCR for Highly Sensitive Detection of MYD88 L265P Mutation

MYD88^L265P is a gain-of-function mutation, arising from the missense alteration c.794T>C, that frequently occurs in B-cell malignancies such as Waldenstrom macroglobulinemia and less frequently in IgM monoclonal gammopathy of undetermined significance (IgM-MGUS) or other lymphomas. MYD88^L265P has been recognized as a relevant diagnostic flag, but also as a valid prognostic and predictive biomarker, as well as an investigated therapeutic target. Up until now, allele-specific quantitative PCR (ASqPCR) has been widely used for MYD88^L265P detection providing a higher level of sensitivity than Sanger sequencing. However, the recently developed droplet digital PCR (ddPCR) shows a deeper sensitivity, compared to ASqPCR, that is necessary for screening low infiltrated samples. Actually, ddPCR could represent an improvement in daily laboratory practice since it allows mutation detection in unselected tumor cells, allowing to bypass the time-consuming and costly B-cell selection procedure. ddPCR accuracy has been recently proved to be suitable also for mutation detection in "liquid biopsy" samples that might be used as a noninvasive and patient-friendly alternative to bone marrow aspiration especially during the disease monitoring. The relevance of MYD88^L265P, both in daily management of patients and in prospective clinical trials investigating the efficacy of novel agents, makes crucial to find a sensitive, accurate, and reliable molecular technique for mutation detection. Here, we propose a protocol for MYD88^L265P detection by ddPCR.

Bing–Neel Syndrome: Update on Diagnosis and Treatment

Bing–Neel syndrome (BNS) is a rare neurological complication of Waldenström macroglobulinaemia. We highlight key issues in clinical presentation, diagnosis, and treatment while focusing on new and emerging therapies available for patients diagnosed with BNS. It is anticipated that further development of Bruton Tyrosine Kinase (BTK) inhibitors and less toxic chemoimmunotherapies will improve treatment delivery and response.

Improving outcomes for patients with lymphoma: design and development of the Australian and New Zealand Lymphoma and Related Diseases Registry

Background

Lymphoma is a malignancy of lymphocytes and lymphoid tissues comprising a heterogeneous group of diseases, with up to 80 entities now described. Lymphoma is the 6^th most common cancer in Australia, affecting patients of all ages, with rising incidence rates. With the proliferation of efficacious novel agents, therapeutic strategies are increasingly diverse and survival is improving. There is a clear need for contemporary robust and detailed data on diagnostic, investigational and management strategies for this disease in Australia, New Zealand and worldwide, to inform and benchmark local and international standards of care. Clinical quality registries can provide these data, and support development of strategies to address variations in management, including serving as platforms for clinical trials and other research activities. The Lymphoma and Related Diseases Registry (LaRDR) was developed to capture details of patient demographics, disease characteristics, and management throughout their disease course and therapy and to develop outcome benchmarks nationally and internationally for lymphoma. This report describes the aims, development and implementation of the LaRDR, as well as challenges addressed in the process.

Methods

The LaRDR was established in 2016 as a multicentre, collaborative project at sites across Australia with a secure online database which collects prospective data on patients with a new diagnosis of lymphoma or chronic lymphocytic leukaemia (CLL). LaRDR development required multidisciplinary participation including specialist haematology, information technology, and biostatistical support, as well as secure funding. Here we describe the database development, data entry, ethics approval process, registry governance and support for participating sites and the coordinating centre.

Results

To date more than 5,300 patients have been enrolled from 28 sites in Australia and New Zealand. Multiple challenges arose during the development, which we describe, along with approaches used to overcome them. Several confirmed international collaborations are now in place, and the registry is providing valuable data for clinicians, researchers, industry and government, including through presentations of results at major national and international conferences.

Conclusion

Challenges in establishing the LaRDR have been successfully overcome and the registry is now a valuable resource for lymphoma clinicians, researchers, health economists and others in Australia, New Zealand and globally.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-022-01728-0.

Nucleic Acid Biomarkers in Waldenström Macroglobulinemia and IgM-MGUS: Current Insights and Clinical Relevance

Waldenström Macroglobulinemia (WM) is an indolent lymphoplasmacytic lymphoma, characterized by the production of excess immunoglobulin M monoclonal protein. WM belongs to the spectrum of IgM gammopathies, ranging from asymptomatic IgM monoclonal gammopathy of undetermined significance (IgM-MGUS), through IgM-related disorders and asymptomatic WM to symptomatic WM. In recent years, its complex genomic and transcriptomic landscape has been extensively explored, hereby elucidating the biological mechanisms underlying disease onset, progression and therapy response. An increasing number of mutations, cytogenetic abnormalities, and molecular signatures have been described that have diagnostic, phenotype defining or prognostic implications. Moreover, cell-free nucleic acid biomarkers are increasingly being investigated, benefiting the patient in a minimally invasive way. This review aims to provide an extensive overview of molecular biomarkers in WM and IgM-MGUS, considering current shortcomings, as well as potential future applications in a precision medicine approach.

CD5-Negative, CD10-Negative Low-Grade B-Cell Lymphoproliferative Disorders of the Spleen

CD5-negative, CD10-negative low-grade B-cell lymphoproliferative disorders (CD5-CD10-LPD) of the spleen comprise a fascinating group of indolent, neoplastic, mature B-cell proliferations that are essential to accurately identify but can be difficult to diagnose. They comprise the majority of B-cell LPDs primary to the spleen, commonly presenting with splenomegaly and co-involvement of peripheral blood and bone marrow, but with little to no involvement of lymph nodes. Splenic marginal zone lymphoma is one of the prototypical, best studied, and most frequently encountered CD5-CD10-LPD of the spleen and typically involves white pulp. In contrast, hairy cell leukemia, another well-studied CD5-CD10-LPD of the spleen, involves red pulp, as do the two less common entities comprising so-called splenic B-cell lymphoma/leukemia unclassifiable: splenic diffuse red pulp small B-cell lymphoma and hairy cell leukemia variant. Although not always encountered in the spleen, lymphoplasmacytic lymphoma, a B-cell lymphoproliferative disorder consisting of a dual population of both clonal B-cells and plasma cells and the frequent presence of the MYD88 L265P mutation, is another CD5-CD10-LPD that can be seen in the spleen. Distinction of these different entities is possible through careful evaluation of morphologic, immunophenotypic, cytogenetic, and molecular features, as well as peripheral blood and bone marrow specimens. A firm understanding of this group of low-grade B-cell lymphoproliferative disorders is necessary for accurate diagnosis leading to optimal patient management.

Trends in Incidence and Mortality of Waldenström Macroglobulinemia: A Population-Based Study

Background: The incidence of Waldenström macroglobulinemia (WM) has increased in certain groups over several decades in the United States. It is unclear whether the increasing incidence is associated with mortality trends. Methods: The incidence and incidence-based mortality (IBM) rates were obtained from the Surveillance, Epidemiology, and End Results (SEER) database (1980-2016) with SEER^*Stat software. The secular trends stratified by demographic characteristics were analyzed by joinpoint regression. Results: The incidence of WM showed an initial rapid increase from 1980 to 1993 {annual percentage change (APC), 14.1% [95% confidence interval (CI), 10 to 18.4%]}, whereas it began to stabilize from 1993 to 2016 [APC, 0.5% (95% CI, -0.3 to 1.3%)]. The WM IBM trend followed a similar pattern, with a decrease occurring around 1994. The trends in the incidence and mortality significantly differed according to geographic location, race, age, sex, primary site of involvement and subtype, which could help in further investigations into the specific etiology. Moreover, a dramatic increase in the 5-year survival rate from the 1980s to 2010s was observed (47.84 vs. 69.41%). Conclusions: Although both the incidence and IBM of WM continued to increase during the study period, a reduction in the rate of increase occurred around 1993. We believe that further advances in healthcare delivery and research can ensure a low mortality rate. Future studies can use the findings of this paper to monitor the results of WM therapy.