Prolonged Fever, Hepatosplenomegaly, and Pancytopenia in a 46-Year-Old Woman

Liran Levy and colleagues discuss the differential diagnosis, investigation, and management of a 46-year-old woman with fever, weakness, night sweats, and weight loss

Single cell dissection of plasma cell heterogeneity in symptomatic and asymptomatic myeloma

Multiple myeloma, a plasma cell malignancy, is the second most common blood cancer. Despite extensive research, disease heterogeneity is poorly characterized, hampering efforts for early diagnosis and improved treatments. Here, we apply single cell RNA sequencing to study the heterogeneity of 40 individuals along the multiple myeloma progression spectrum, including 11 healthy controls, demonstrating high interindividual variability that can be explained by expression of known multiple myeloma drivers and additional putative factors. We identify extensive subclonal structures for 10 of 29 individuals with multiple myeloma. In asymptomatic individuals with early disease and in those with minimal residual disease post-treatment, we detect rare tumor plasma cells with molecular characteristics similar to those of active myeloma, with possible implications for personalized therapies. Single cell analysis of rare circulating tumor cells allows for accurate liquid biopsy and detection of malignant plasma cells, which reflect bone marrow disease. Our work establishes single cell RNA sequencing for dissecting blood malignancies and devising detailed molecular characterization of tumor cells in symptomatic and asymptomatic patients

Learning from Patients: The Interplay between Clinical and Laboratory Research in AL Amyloidosis

Primary systemic light chain amyloidosis (AL) is a rare monoclonal plasma cell disorder. Much research has been performed to determine the factors that underly amyloidogenicity. However, there is increasing evidence that the primary clone, and also patient-related factors, influence the mechanism and rate of the process. The lessons learnt from patient care definitely imply that this is not solely due to the deposition of material in the tissues that cause organ injury but amyloid light chain precursors are likely to mediate cellular toxicity. The disease rarity, combined with the lack of in vitro tools, and that multi-organ failure has a wide clinical spectrum, result in investigative challenges and treatment limitations (due to AL patient frailty). All these characteristics make the disease difficult to diagnose and indicate the need to further study its origins and treatments. This review will focus on the various aspects of the amyloidogenic plasma cell clone, as learnt from the patient care and clinics, and its implications on basic as well as clinical trials of AL research. Details regarding the etiology of the plasma cell clone, understanding the diagnosis of AL, and improvement of patient care with specific consideration of the future perspectives of individualized patient therapy will be described

Learning from Patients: The Interplay between Clinical and Laboratory Research in AL Amyloidosis

Primary systemic light chain amyloidosis (AL) is a rare monoclonal plasma cell disorder. Much research has been performed to determine the factors that underly amyloidogenicity. However, there is increasing evidence that the primary clone, and also patient-related factors, influence the mechanism and rate of the process. The lessons learnt from patient care definitely imply that this is not solely due to the deposition of material in the tissues that cause organ injury but amyloid light chain precursors are likely to mediate cellular toxicity. The disease rarity, combined with the lack of in vitro tools, and that multi-organ failure has a wide clinical spectrum, result in investigative challenges and treatment limitations (due to AL patient frailty). All these characteristics make the disease difficult to diagnose and indicate the need to further study its origins and treatments. This review will focus on the various aspects of the amyloidogenic plasma cell clone, as learnt from the patient care and clinics, and its implications on basic as well as clinical trials of AL research. Details regarding the etiology of the plasma cell clone, understanding the diagnosis of AL, and improvement of patient care with specific consideration of the future perspectives of individualized patient therapy will be described

Immune Therapies in AL Amyloidosis—A Glimpse to the Future

Light-chain (AL) amyloidosis is a rare plasma cell disorder characterized by the deposition of misfolded immunoglobulin light chains in target organs, leading to multi-organ dysfunction. Treatment approaches have historically mirrored but lagged behind those of multiple myeloma (MM). Recent advancements in MM immunotherapy are gradually being evaluated and adopted in AL amyloidosis. This review explores the current state of immunotherapeutic strategies in AL amyloidosis, including monoclonal antibodies, antibody–drug conjugates, bispecific antibodies, and chimeric antigen receptor T-cell therapy. We discuss the unique challenges and prospects of these therapies in AL amyloidosis, including the exposure of frail AL amyloidosis patients to immune-mediated toxicities such as cytokine release syndrome (CRS) and immune effector-cell-associated neurotoxicity syndrome (ICANS), as well as their efficacy in promoting rapid and deep hematologic responses. Furthermore, we highlight the need for international initiatives and compassionate programs to provide access to these promising therapies and address critical unmet needs in AL amyloidosis management. Finally, we discuss future directions, including optimizing treatment sequencing and mitigating toxicities, to improve outcomes for AL amyloidosis patients

Understanding the Bioactivity and Prognostic Implication of Commonly Used Surface Antigens in Multiple Myeloma

Multiple myeloma (MM) progression is dependent on its interaction with the bone marrow microenvironment and the immune system and is mediated by key surface antigens. Some antigens promote adhesion to the bone marrow matrix and stromal cells, while others are involved in intercellular interactions that result in differentiation of B-cells to plasma cells (PC). These interactions are also involved in malignant transformation of the normal PC to MM PC as well as disease progression. Here, we review selected surface antigens that are commonly used in the flow cytometry analysis of MM for identification of plasma cells (PC) and the discrimination between normal and malignant PC as well as prognostication. These include the markers: CD38, CD138, CD45, CD19, CD117, CD56, CD81, CD27, and CD28. Furthermore, we will discuss the novel marker CD24 and its involvement in MM. The bioactivity of each antigen is reviewed, as well as its expression on normal vs. malignant PC, prognostic implications, and therapeutic utility. Understanding the role of these specific surface antigens, as well as complex co-expressions of combinations of antigens, may allow for a more personalized prognostic monitoring and treatment of MM patients

Bone marrow aspirate showing monocytes (red arrows) engulfing red blood cell precursors (black arrows).

<p>(Giemsa stain.)</p