Heavy/light chain assay in the monitoring of multiple myeloma. Ting Huong Yew,Sthaneshwar Pavai,Bee Ping Chong,Shanmugam Hemalatha,Lim Merrell Pathology Serum protein (SPE) and immunofixation electrophoresis (IFE) have been extensively validated for the routine use of identifying, characterising and quantifying monoclonal proteins. However, accurate quantitation of IgA monoclonal proteins can be difficult when they migrate in to the β fraction, due to co-migration with transferrin and complement components. The heavy/light chain (HLC) immunoassay is an additional tool for measuring intact immunoglobulin monoclonal proteins. Therefore, we aimed to examine the clinical utility of the HLC assay for the disease monitoring of IgG and IgA multiple myeloma (MM) patients. A total of 177 samples from 30 MM patients (21 IgG and 9 IgA) were analysed retrospectively with median number of six follow up samples per patient (range 3-13). Serum free light chains (sFLC) and HLC were quantified using Freelite and Hevylite immunoassays. Details of M-protein concentration, β-globulin levels, total immunoglobulin levels and disease treatment response were obtained from the laboratory and patient information system. Passing-Bablok regression analysis was performed to compare (i) M-protein quantification with involved HLC (iHLC) and (ii) total immunoglobulin with summated HLC pairs for each immunoglobulin type (e.g., IgGκ+IgGλ). For 127 IgG MM samples, IgG iHLC levels showed a good correlation with SPE quantification (iHLC y=0.96x+4.9; r=0.917) and summated HLC showed a good correlation with total IgG concentration (summated HLC y=0.94x+5.74; r=0.91). In total, 95/127 (75%) IgG MM follow-up samples had an abnormal HLC ratio and 122/127 (96%) had a positive SPE, probably due to the lower sensitivity of HLC assay in detecting clonality in patients with IgG MM. Consistent with this, one patient assigned a very good partial response by International Myeloma Working Group criteria would be assigned a complete response based on HLC measurements. For 50 IgA MM samples, 42/50 (84%) had an abnormal HLC ratio. Conversely, 50/50 (100%) of M-proteins showed β fraction migration and were difficult to accurately quantify by SPE. Therefore, M-protein concentration and iHLC did not correlate as well in IgA MM (y=1.9x-8.4; r=0.8) compared to IgG MM. However, there was good correlation between total IgA and summated IgA HLC (IgAκ+IgAλ y=1.35x-0.33; r=0.95). Of the 8/50 (16%) IgA samples with a normal HLC ratio, 6/8 (75%) were consistent with the disease status being in complete remission. Interestingly, in one IgA MM patient, SPE and IFE were negative, but the serum FLC ratio and involved FLC were highly abnormal, consistent with the presence of light chain escape. Our data suggest HLC measurements could add value to the current disease monitoring of MM patients. In IgG MM patients, the M-protein level correlated well with HLC values. The HLC assay complements the serum FLC assay and is especially useful for monitoring of IgA MM patients who display M-proteins migrating in the β region on SPE. 10.1016/j.pathol.2019.04.002

[The prognostic significance of dynamic monitoring of minimal residual disease (MRD) status in patients with newly-diagnosed multiple myeloma]. Yang P Y,Liu M M,Fan H Q,Yang Y P,Han W,Yu X Y,Yue T T,Su K J,Guo Q,Gao S J,Jin F Y Zhonghua xue ye xue za zhi = Zhonghua xueyexue zazhi To evaluate the prognostic value of kinetic changes in minimal residual disease (MRD) status, as well as its relationship with risk stratification, therapeutic response and treatment in patients with newly-diagnosed multiple myeloma (MM) . A total of 135 patients with newly-diagnosed MM were screened, and 105 patients who achieved VGPR or more as the best responses were included into this study. The MRD status was determined by multiparameter flow cytometry (MFC) at multiple intervals after two cycles of treatment until clinical relapse, death, or last follow-up. The statistical methods included Kaplan-Meier analysis, Cox regression, etc. ①In all 135 patients, 57.8% (78/135) patients achieved MRD negativity (MRD(-)) after treatment. In 105 patients who achieved VGPR and thus included in this study, the MRD(-) rate was 72.4% (76/105) , with a median interval of 3 months from starting treatment to achievement of MRD(-) status. ②The 2-year PFS rate of patients with MRD(-) status was significantly higher than that of MRD(+) status (62.2% 41.3%, =0.001) , while MRD persistence (MRD(+)) was an independent factor for poor prognosis (multivariate analysis for PFS: =0.044, =3.039, 95% 1.029-8.974) . ③Loss of MRD(-) status (i.e., MRD reappearance) showed inferior outcomes compared with MRD sustained negative ones, the PFS was 18 months versus not reach (<0.001) and the OS was not reach for both (=0.002) . ④The 2-year PFS and OS rates of patients with duration of MRD(-)status≥12 months were significantly higher than those of the control group (PFS: 77.7% 36.7%, <0.001; OS: 96.4% 57.9%, <0.001 respectively) . Duration of MRD(-) status was associated with a marked reduction in risk of relapse or death (univariate analysis for PFS: <0.001, =0.865, 95% 0.815-0.918; for OS: =0.001, =0.850, 95% 0.741-0.915 respectively) . ⑤Moreover, even in patients carrying high-risk cytogenetic abnormalities (CA) or ineligible for ASCT, MRD negativity remained its prognostic value to predict PFS (high-risk CA medianPFS: not reach vs 19 months, =0.006; ineligible for ASCT medianPFS: not reach 25 months, =0.052 respectively) . ⑥Last, treatment with the bortezomib-based regimens contributed to prolonged MRD(-) duration (median MRD(-) duratio: 25 months 10 months, =0.034) . Our findings supported MRD(+) status as an independent poor prognostic factor in MM patients, which implicated that duration of MRD(-) status also played a significant role in evaluation of prognosis, while loss of MRD(-)status might serve as an early biomarker for relapse. Therefore, monitoring of MRD kinetics might more precisely predict prognosis, as well as guide treatment decision, especially for when to start retreatment in relapsed patients. 10.3760/cma.j.issn.0253-2727.2019.07.009

Risk Stratification of Precursors to Multiple Myeloma in 2020. Chudasama Rani,Barth Peter Rhode Island medical journal (2013) With advances in the treatment of plasma cell disorders, there have also been improvements in the risk stratification of these diseases. There are currently no screening recommendations for monoclonal gammopathy of unknown significance (MGUS); however, new studies are analyzing the role of screening for patients age 40-75 who are African American or have a family history of multiple myeloma (MM). Patients with smoldering multiple myeloma (SMM) have an increased risk of progression to MM when compared to MGUS. Data have shown that evaluation of bone marrow biopsy, full body MRI and free light chain ratios can identify high-risk SMM patients. Current investigation into early initiation of treatment for patients with SMM who do not meet criteria for MM showed improvement in time to progression. By continuing to evaluate clinical markers of disease burden, physicians can risk stratify patients to identify those at highest risk for progression to MM.

Expert Panel Consensus Statement for Proper Evaluation of First Relapse in Multiple Myeloma. Offidani M,Boccadoro M,Di Raimondo F,Petrucci M T,Tosi P,Cavo M Current hematologic malignancy reports PURPOSE OF REVIEW:A working group of six expert physicians convened to assess the spectrum of multiple myeloma relapse presentations, discussed the features that can define the disease as aggressive and not aggressive, and established whether this information could help in selecting treatment together with the characteristics of disease and of patients and type of prior therapy. RECENT FINDINGS:The working group agreed that relapse should be distinguished between biochemical and clinical according to IMWG. Moreover, the expert panel defined "aggressive disease" as a clinical condition that requires therapy able to induce a rapid and as deep as possible response to release symptoms and to avoid impending danger of new events. According to this definition, relapse was considered aggressive if it presents with at least one of the following features: doubling of M protein rate over 2 months, renal insufficiency, hypercalcemia, extramedullary disease, elevated LDH, high plasma cell proliferative index, presence of plasma cells in peripheral blood, or skeletal-related complications. Moreover, the panel agreed that this classification can be useful to choose therapy in first relapse together with other patient, disease, and prior therapy characteristics. So, this item was included in a new therapeutic algorithm. The treatment choice in MM at relapse is wider than in the past with the availability of many new therapeutic regimens leading to increased diversity of approaches and relevant risk of inappropriate treatment decisions. A practical classification of relapses into aggressive or non-aggressive, included in a decisional algorithm on MM management at first relapse, could help to make the appropriate treatment decisions. 10.1007/s11899-019-00507-x

Multiple Myeloma: Diagnosis and Treatment. Michels Thomas C,Petersen Keith E American family physician Multiple myeloma accounts for 1.6% of all cancer cases and approximately 10% of hematologic malignancies in the United States. In 2015, an estimated 28,850 new cases of multiple myeloma were diagnosed in the United States, and the disease caused more than 11,000 deaths. Patients older than 65 years account for 85% of those diagnosed with multiple myeloma, and there is a twofold increased incidence in blacks compared with whites. Patients may present with bone pain or with symptoms that are often nonspecific, such as nausea, vomiting, malaise, weakness, recurrent infections, and weight loss. Many patients present with only laboratory abnormalities, such as anemia, renal disease, and elevated protein levels. The diagnosis of multiple myeloma requires increased numbers of immature, abnormal, or atypical plasma cells in the bone marrow; a monoclonal protein in the serum or urine; or characteristic bone lesions. The diagnostic workup in a patient with suspected multiple myeloma should include a complete blood count with differential; serum chemistries; creatinine, lactate dehydrogenase, and beta2-microglobulin tests; immunoglobulin studies; skeletal survey; and bone marrow evaluation. Initiation of chemotherapy and assessment of eligibility for autologous stem cell transplantation require referral to an oncologist. Most patients with multiple myeloma will receive thromboprophylaxis, bisphosphonate therapy, and prophylaxis against infection at some point in their treatment. Family physicians play a role in assessing these patients for infection, adverse treatment effects, and renal and thrombotic complications, and in managing issues related to pain, nutrition, and psychosocial support.