Prognosis of young patients with monoclonal gammopathy of undetermined significance (MGUS)

Transient monoclonal gammopathy: a single-center study

OBJECTIVES

Some of the monoclonal gammopathy of uncertain significance are transient monoclonal gammopathies, characterized by the appearance of a small serum paraprotein followed by its disappearance after a variable period of time. The aim of the present study is to examine the transient monoclonal gammopathies in our health area by describing their characteristics, as well as the pathology they presented at the time of the development of the monoclonal gammopathy.

METHODS

A retrospective study was undertaken, in which all serum protein electrophoresis patterns performed during a 6-month period (January-2024/June-2024) were reviewed. All these serum protein electrophoresis were processed in the clinical analysis service of the Clinical Universitary Hospital of Santiago de Compostela from primary and secondary care of the Sanitary Area of Santiago de Compostela and Barbanza. Only patients without hematologic pathology who presented a serum protein electrophoresis without monoclonal gammopathy and who had previously presented a serum protein electrophoresis with the presence of monoclonal gammopathy were selected.

RESULTS

A total of 80 transient monoclonal gammopathies were identified, of which 68 had a monoclonal pattern (85%) and 12 had an oligoclonal pattern (15%). We found different diagnoses coinciding with the presence of transient monoclonal gammopathy, among which we can highlight: 35 cases (43.7%) were infectious processes, 20 cases (25%) were autoimmune diseases and 12 cases (15%) were transplant patients.

CONCLUSIONS

Clinicians should consider the likelihood of a transient paraprotein to avoid unnecessary investigations and invasive procedures, which are used in case of suspected malignancy or persistent monoclonality.

Associations Between Patient Characteristics and Progression to Multiple Myeloma Among Patients With Monoclonal Gammopathy of Undetermined Significance: A Systematic Review

Monoclonal gammopathy of undetermined significance (MGUS) is a pre-malignant condition of multiple myeloma (MM). Evidence suggested old age, black race, male gender, and obesity as risk factors for MGUS development; however, whether they are associated with an increased risk of progression to MM among patients with MGUS is unclear. A systematic search of PUBMED and EMBASE for cohort studies investigating the association between age/race/gender/obesity and progression to MM. We used the Newcastle-Ottawa Scale (NOS) to assess the methodologic quality of the included studies. Summary risk ratios were calculated using random-effects models. We identified 24 publications, of which 17 articles were included in the main analyses. Overall, the quality of the studies was fair (mean NOS = 5.5). Our meta-analyses showed that old age was positively associated with the risk of the MGUS-MM progression (risk ratio: 2.38; 95% confidence interval [CI] 1.59-3.57), while race was not statistically significantly associated with the risk (blacks vs whites: 1.09; 95% CI: 0.77-1.54). Males had a lower risk of MGUS-MM progression, compared to females (risk ratio: 0.70; 95% CI 0.50-1.0; P-value = .048). High body mass index was significantly associated with an increased risk of MGUS-MM progression (risk ratio: 1.32; 95% CI 1.12-1.57). Based on extant research, old age, female sex, and obesity may be implicated in MGUS-MM progression. However, several studies which found an insignificant association between age/gender and progression did not report the risk estimates. Publication bias exists and our risk estimates may be overestimated. More studies are warranted to confirm our findings.

Development of hyperdiploidy starts at an early age and takes a decade to complete

ABSTRACT

Nearly half of patients with multiple myeloma (MM) have hyperdiploidy (HMM) at diagnosis. Although HMM occurs early, the mutational processes before and after hyperdiploidy are still unclear. Here, we used 72 whole-genome sequencing samples from patients with HMM and identified pre- and post-HMM mutations to define the chronology of the development of hyperdiploidy. An MM cell accumulated a median of 0.56 mutations per megabase before HMM, and for every clonal pre-HMM mutation, 1.21 mutations per megabase accumulated after HMM. This analysis using mutations before and after hyperdiploidy shows that hyperdiploidy happens after somatic hypermutation. Prehyperdiploidy mutations are activation-induced cytidine deaminase and age/clock-like signature driven, whereas posthyperdiploidy mutations are from DNA damage and APOBEC. Interestingly, the first hyperdiploidy event occurred within the first 3 decades of life and took a decade to complete. Copy number changes affecting chromosomes 15 and 19 occurred first. Finally, mutations before initiating event affected chromosomes at different rates, whereas post-initiating event mutational processes affect each chromosome equally.

Vacuolar myopathy with monoclonal gammopathy and stiffness (VAMMGAS)

BACKGROUND

Monoclonal gammopathy (MG) has been reported in association with numerous neurological disorders but the spectrum of MG-associated myopathies remains poorly described.

OBJECTIVE

To report a newly acquired myopathy associated with MG.

METHODS

Three adult patients with the same phenotype from two French referral centers were prospectively analyzed. Clinical, electrophysiological, muscle biopsy data, and patients' outcomes under treatment are reported.

RESULTS

The patients, aged 37, 46, and 56 years, presented progressive weakness with subacute worsening and stiffness, in the context of severe weight loss. The weakness mainly involved the proximal limbs and axial muscles. Creatine kinase levels were 1400-2900 IU/L and electromyography revealed a myopathic pattern with spontaneous complex repetitive discharges. Muscle biopsies showed vacuoles containing glycogen and autophagic material along with the presence of sarcolemmal complement membrane attack complex deposits. There was no evidence of a genetic glycogen metabolic disorder. IgGκ monoclonal gammopathy was identified in all cases, without signs of lymphoplasmocytic proliferation. All patients improved with a treatment combining corticosteroids, intravenous immunoglobulins, and immunosuppressants, and two patients recovered walking ability.

CONCLUSION AND RELEVANCE

We report a new muscle disease defined by a vacuolar myopathy characterized by axial and proximal muscle weakness with prominent stiffness and high frequency discharges on electromyography associated with monoclonal gammopathy, defined under the acronym VAMMGAS.

Warning values of serum total kappa/lambda ratio for M-proteinemia

BACKGROUND

To introduce the serum total kappa/lambda ratio (K/L) in humoral immunity testing reports to improve the detection rate of M-proteinemia.

METHODS

156 M protein-positive and 5464 M protein-negative samples confirmed by serum immunofixation electrophoresis(sIFE) were accumulated from January 2021 to December 2023 in the First Affiliated Hospital of Soochow University and the contents of immunoglobulins (IgG, IgA, IgM, kappa and lambda) were tested by Beckman IMMAGE800. All the samples were divided into two groups by time: the modeling group and the validation group. The K/L values in the modeling group were analyzed by SPSS 27.0 to get the receiver operating characteristic curve (ROC). Furthermore, a more in-depth analysis was conducted to verify the reliability of the optimal cutoff values in the validation group. In addition, the levels of immunoglobulins of another group including 106 patients with definite diagnosis of monoclonal gammopathy ranging from January 2021 to June 2024 were traced back to improve the diagnostic efficiency.

RESULTS

The optimal cutoff values of K/L were 2.31 and 1.43 corresponding to K-type and L-type M-proteinemia respectively by ROC analysis. The sensitivity and specificity were validated as 76.14% and 77.42%. False positives were mainly found in samples with systemic sclerosis (36.84%), hypohepatia (28.71%) and sicca syndrome (27.27%). While false negatives were mainly found in IgA monoclonal gammopathy (38.39%) and IgM monoclonal gammopathy (28.57%). Combining with the detection rules of IgG, IgA and IgM, the sensitivities for the diagnosis of immunoglobulin light chain amyloidosis(AL) and monoclonal gammopathy of undetermined significance(MGUS) can be increased to 83.33% and 85%.

CONCLUSIONS

K/L > 2.31 and K/L < 1.43 can be used as warning values for M-proteinemia. In addition, the content of the heavy chain in IgA- or IgM-type M-proteinemia may be considered to improve the detection rate.

Monoclonal gammopathy of clinical significance in a young patient treated with melphalan-thalidomide-prednisone

Key Clinical Message

We report an observation of a young patient presenting with severe type 1 cryoglobulinemic vasculitis revealing a monoclonal gammopathy of clinical significant. Treatment with Melphalan-Thalidomide Prednisone improved the symptoms. Early diagnosis would prevent serious tissue damage.

Abstract

Monoclonal gammopathy encompass diverse clinical forms. Only the cancerous form, multiple myeloma (MM), is treated based on specific diagnostic criteria. A new clinical entity, monoclonal gammopathy of clinical significance (MGCS), warrants special attention due to its need for specific treatment. It involves patients with signs of potentially severe organ involvement that do not meet MM criteria. We present the case of a 34-year-old Malagasy woman with severe type I cryoglobulinemic vasculitis associated with noncancerous monoclonal gammopathy, showing a favorable outcome after treatment with Thalidomide. Symptoms included toe necrosis, a severe ulcer on the left calf evolving for 3 months, and stocking-like dysesthesias. Investigations revealed monoclonal gammopathy at 30.1 g/L, proteinuria at 1 g/24 h, medullary plasma cell at 6%, and circulating cryoglobulin of Ig kappa type. CRAB criteria (anemia, hypercalcemia, renal insufficiency, and osteolysis) were absent. Treatment with Thalidomide, combined with corticosteroids and local care for 4 months, resulted in ulcer healing, disappearance of dysesthesias, and persistent normalization of gammaglobulin. Our case underscores the importance of specific treatment for MGCS.

Differential Diagnosis and Therapeutic Advances in Multiple Myeloma: A Review Article

Multiple myeloma (MM) is a hematologic malignancy characterized by the abnormal clonal proliferation of plasma cells that may result in focal bone lesions, renal failure, anemia, and/or hypercalcemia. Recently, the diagnosis and treatment of MM have evolved due to a better understanding of disease pathophysiology, improved risk stratification, and new treatments. The incorporation of new drugs, including proteasome inhibitors, immunomodulatory drugs, anti-CD38 antibodies and high-dose chemotherapy followed by hematopoietic stem cell transplantation, has resulted in a significant improvement in patient outcomes and QoL. In this review, we summarize differential diagnoses and therapeutic advances in MM.

Monoclonal gammopathy of increasing significance: time to screen?

Monoclonal gammopathy (MG) is a frequently detected clonal B-cell or plasma-cell disorder. Importantly, every multiple myeloma (MM) case is preceded by MG. Although clinical algorithms now allow earlier treatment of patients with biomarkers of malignancy before MM-induced tissue damage (CRAB) occurs, most patients are still diagnosed late. It is important to revisit how MG should be managed in clinical practice and whether screening is required. As the prevalence of MG and other medical co-morbidities both rise with increasing age, the degree of contribution of MG to disease states other than malignant progression is often unclear. This can lead to monitoring lapses and under recognition of the organ dysfunction that can occur with monoclonal gammopathy of clinical significance (MGCS). Therefore, models of progression to MM and/or MGCS require further refinement. While MG is currently detected incidentally, a case for screening has been made with ongoing studies in this area. Screening has the potential benefit of earlier detection and prevention of both MGCS and delayed MM presentations, but important drawbacks include the psychosocial impact on individuals and resource burden on healthcare services. MG terminology should transition alongside our increasing understanding of the condition and genomic characterization that have already begun to revise the MG nomenclature. The biology of MG has been poorly understood and is often inferred from the biology of MM, which is unhelpful. We review the literature and case for MG screening in this paper. In particular, we highlight areas that require focus to establish screening for MG.

Acute venous thromboembolic events in patients with monoclonal gammopathy of undetermined significance: An analysis of the National Inpatient Sample

BACKGROUND

Monoclonal Gammopathy of Undetermined Significance (MGUS) is a premalignant plasma cell disorder which despite being clinically silent carries an increased risk of venous thromboembolism (VTE). We conducted a population-based study to investigate the risk of VTE in these patients.

METHODS

We utilized the National Inpatient Sample (NIS) for the year 2016 to compare the incidence of acute VTE between patients who carry the diagnosis of MGUS and those who don't. We excluded hospitalizations with age < 18 years and those that had a diagnosed lymphoma, leukemia, solid malignancy, or other plasma cell dyscrasia. We utilized the ICD-10-CM coding system to search the database for codes of VTE, MGUS, and other comorbid conditions. Multivariate logistic regression models were used for comparative analysis adjusting for demographic characteristics and comorbidities. Baseline comorbidities were described as frequencies and proportions for categorical variables and as medians with interquartile ranges for continuous variables.

RESULTS

A total of 33,115 weighted hospitalizations were included in the MGUS group. These were compared to 27,418,403 weighted hospitalizations without the diagnosis of MGUS. The MGUS group had higher odds of composite venous thromboembolism (adjusted OR 1.33, 95 % CI 1.22-1.44), deep vein thrombosis (adjusted OR 1.46, 95 % CI 1.29-1.65), and pulmonary embolism (adjusted OR 1.22, 95 % CI 1.09-1.37).

CONCLUSION

Patients with MGUS had increased odds of developing acute venous thromboembolism compared to patients with no history of MGUS.

Monoclonal gammopathy of undetermined significance: evaluation, risk assessment, management, and beyond

Monoclonal gammopathy of undetermined significance (MGUS) is a premalignant state for a spectrum of lymphoplasmacytic malignancies. The risk of progression of MGUS to a symptomatic therapy requiring plasma cell dyscrasia is about 1% per year. Studies carried out over the previous 10 years have improved risk stratification of MGUS based on serologic and genomic evaluations, which has led to better management of patients. In this review, we address the epidemiology, diagnosis, and pathogenesis of MGUS and discuss risk-adapted best practice approaches to monitor patients.

Serum Abnormal Metabolites for Evaluating Therapeutic Response and Prognosis of Patients With Multiple Myeloma

Aims

To evaluate abnormal metabolites related to treatment response and prognosis of multiple myeloma (MM) patients through ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS).

Methods

Forty-six symptomatic MM patients were included in this study who had a prior high level of positive monoclonal proteins before receiving targeted therapy with bortezomib-based regimens. UPLC-MS along with traditional immunofixation was performed on MM diagnostic samples and effective serum samples, and UPLC-MS was used to target valuable metabolic markers related to M protein.MM patients were segregated into pre-therapy (pre-T) and post-therapy (post-T) groups according to the response after chemotherapy. A monoclonal protein could be detected at baseline in 33 newly diagnosed MM (NDMM), 13 refractory and relapsed MM (RRMM) patients and 20 healthy controls (HC) by immunofixation.

Results

Between pre-T and post-T patients, the data showed that 32, 28 and 3 different metabolites were significantly correlated with M protein in IgG, IgA and light chain-type MM, respectively. These identified metabolites were significantly enriched in arginine and proline metabolism as well as glycerophospholipid metabolism pathways. Among them, PC (19:0/22:2) was displayed to increase significantly and consistently with M protein in each subtype of MM after treatment, which obviously indicated that it was related to the treatment response of MM. Further survival analysis of metabolic markers found that aspartic acid, LysoPE (16:0), SM (d18:1/17:0), PC (18:0/24:1), PC (16:0/16:0), TG (18:1/18:1/22:5) and LysoPE (18:2) reaching a certain cutoff value may be associated with shorter progression free survival (PFS). Finally, Cox multivariate regression analysis identified three factors were independent prognostic factors of MM. Moreover, there were significantly different in PC (19:0/22:2) and in aspartic acid between MM patients and healthy people.

Conclusion

This work identified significant metabolic disorders in 46 pairs off pre- and post-therapy MM patients, specifically in arginine, proline and glycerophospholipid pathways. The abnormal metabolites have the potential to serve as new biomarkers for evaluating treatment response and prognosis, as well as early monitoring of disease activity. Therefore, these systematic studies on abnormal metabolites as biomarkers for diagnosis and treatment will provide the evidence for future precise treatment of MM.

A Comprehensive Review of the Genomics of Multiple Myeloma: Evolutionary Trajectories, Gene Expression Profiling, and Emerging Therapeutics

Multiple myeloma (MM) is a blood cancer characterized by the accumulation of malignant monoclonal plasma cells in the bone marrow. It develops through a series of premalignant plasma cell dyscrasia stages, most notable of which is the Monoclonal Gammopathy of Undetermined Significance (MGUS). Significant advances have been achieved in uncovering the genomic aberrancies underlying the pathogenesis of MGUS-MM. In this review, we discuss in-depth the genomic evolution of MM and focus on the prognostic implications of the accompanied molecular and cytogenetic aberrations. We also dive into the latest investigatory techniques used for the diagnoses and risk stratification of MM patients.