Sarah Bonnet

Impact of Initial FDG-PET/CT and Serum-Free Light Chain on Transformation of Conventionally Defined Solitary Plasmacytoma to Multiple Myeloma

Purpose: Solitary plasmacytoma (SP) is a localized proliferation of monoclonal plasma cells in either bone or soft tissue, without evidence of multiple myeloma (MM), and whose prognosis is marked by a high risk of transformation to MM. Experimental Design: We studied the impact of FDG-PET/CT (2[18F]fluoro-2-deoxy-D-glucose positron emission tomography–computed tomography) on the risk of transformation of SP to overt MM among other markers in a series of 43 patients diagnosed with SP. Results: Median age was 57.5 years; 48% of patients had an abnormal involved serum-free light chain (sFLC) value, and 64% had an abnormal sFLC ratio at diagnosis. Thirty-three percent had two or more hypermetabolic lesions on initial PET/CT, and 20% had two or more focal lesions on initial MRI. With a median follow-up of 50 months, 14 patients transformed to MM with a median time (TTMM) of 71 months. The risk factors that significantly shortened TTMM at diagnosis were two or more hypermetabolic lesions on PET/CT, abnormal sFLC ratio and involved sFLC, and to a lesser extent at completion of treatment, absence of normalized involved sFLC and PET/CT or MRI. In a multivariate analysis, abnormal initial involved sFLC [OR = 10; 95% confidence interval (CI), 1–87; P = 0.008] and PET/CT (OR = 5; 95% CI, 0–9; P = 0.032) independently shortened TTMM. Conclusions: An abnormal involved sFLC value and the presence of at least two hypermetabolic lesions on PET/CT at diagnosis of SP were the two predictors of early evolution to myeloma in our series. This data analysis will need confirmation in a larger study, and the study of these two risk factors may lead to a different management of patients with SP in the future. Clin Cancer Res; 20(12); 3254–60. ©2014 AACR.

IgA kappa/IgA lambda heavy/light chain assessment in the management of patients with IgA myeloma

Accurate quantification of immunoglobulin A (IgA) monoclonal immunoglobulins by serum protein electrophoresis (SPEP) can be difficult and can impact the assessment of response among patients with multiple myeloma (MM). Therefore, there is a need to identify new assays that better reflect disease burden and response to treatment, and correlate with patient outcome. IgA Hevylite (HLC) measures IgA kappa and IgA lambda separately and provides precise quantitative measurements of the monoclonal IgA expression and polyclonal‐isotype matched suppression. In the current study, the authors assessed the usefulness of these assays in the diagnosis of IgA MM and sought to comment on the prognostic value of the assays.

Efficacy and safety profile of long-term exposure to lenalidomide in patients with recurrent multiple myeloma.

Lenalidomide in combination with dexamethasone (Len/Dex) is indicated for patients with recurrent/refractory multiple myeloma (RRMM) who were treated with 1 prior therapy until evidence of disease progression. The objective of the current study was to determine the efficacy and safety profile of long‐term exposure to Len/Dex.

IgMκ and IgMλ Measurements for the Assessment of Patients with Waldenström's Macroglobulinaemia

Purpose: Accurate quantification of monoclonal IgM immunoglobulins is essential for response assessment in patients with Waldenströms macroglobulinaemia (WM). The propensity of IgM to form multimers in serum makes sample evaluation by current laboratory methods particularly challenging. Experimental Design: We assessed the precision and linearity of IgMκ and IgMλ heavy/light chain (HLC, Hevylite) assays, and established reference intervals using 120 normal donor sera. We compared the quantitative performance of HLC assays with serum protein electrophoresis (SPE) and total IgM nephelometry for 78 diagnostic samples and follow-up samples from 25 patients with WM. Comparisons were made between the three methods for diagnostic sensitivity and response assessment. Results: IgMκ and IgMλ HLC assays showed low imprecision and good linearity. There was good agreement between summated HLC (IgMκ + IgMλ) and total IgM (measured nephelometrically; R2 = 0.90), but only moderate agreement between involved IgM HLC and SPE densitometry (R2 = 0.49). Analysis of 120 normal donor sera produced the following normal ranges: IgMκ: 0.29–1.82 g/L; IgMλ: 0.17–0.94 g/L; IgMκ/IgMλ ratio: 0.96–2.30. Using these ranges, IgM HLC ratios were abnormal in all WM presentation sera tested, including 15 with non-quantifiable SPE. Despite discordance in quantitation, responses assigned with HLC assays showed excellent agreement to those based on international guidelines using SPE or total IgM; although abnormal HLC ratios indicated residual disease in some patients with negative electrophoresis results. Conclusions: Nephelometric assessment of IgMκ and IgMλ HLC pairs offers a quantitative alternative to traditional laboratory techniques for the measurement of monoclonal IgM and may aid in the management of WM. Clin Cancer Res; 22(20); 5152–8. ©2016 AACR.

IgMκ and IgMl measurements for the assessment of patients with Waldenstrӧm's macroglobulinaemia

Purpose: Accurate quantification of monoclonal IgM immunoglobulins is essential for response assessment in patients with Waldenströms macroglobulinaemia (WM). The propensity of IgM to form multimers in serum makes sample evaluation by current laboratory methods particularly challenging. Experimental Design: We assessed the precision and linearity of IgMκ and IgMλ heavy/light chain (HLC, Hevylite) assays, and established reference intervals using 120 normal donor sera. We compared the quantitative performance of HLC assays with serum protein electrophoresis (SPE) and total IgM nephelometry for 78 diagnostic samples and follow-up samples from 25 patients with WM. Comparisons were made between the three methods for diagnostic sensitivity and response assessment. Results: IgMκ and IgMλ HLC assays showed low imprecision and good linearity. There was good agreement between summated HLC (IgMκ + IgMλ) and total IgM (measured nephelometrically; R2 = 0.90), but only moderate agreement between involved IgM HLC and SPE densitometry (R2 = 0.49). Analysis of 120 normal donor sera produced the following normal ranges: IgMκ: 0.29–1.82 g/L; IgMλ: 0.17–0.94 g/L; IgMκ/IgMλ ratio: 0.96–2.30. Using these ranges, IgM HLC ratios were abnormal in all WM presentation sera tested, including 15 with non-quantifiable SPE. Despite discordance in quantitation, responses assigned with HLC assays showed excellent agreement to those based on international guidelines using SPE or total IgM; although abnormal HLC ratios indicated residual disease in some patients with negative electrophoresis results. Conclusions: Nephelometric assessment of IgMκ and IgMλ HLC pairs offers a quantitative alternative to traditional laboratory techniques for the measurement of monoclonal IgM and may aid in the management of WM. Clin Cancer Res; 22(20); 5152–8. ©2016 AACR.

Maintenance dans le myélome multiple chez les sujets jeunes et les sujets âgés

hma.2012.0704 Auteur(s) : Guillemette Fouquet guillemette.fouquet@gmail.com, Julie Gay, Helene Demarquette, Sarah Bonnet, Xavier Leleu Service des maladies du sang, hopital Huriez, CHRU, Lille Tires a part : G. Fouquet De nombreux progres ont ete realises ces dernieres annees dans le traitement du myelome multiple, chez les sujets jeunes comme chez les sujets âges. Ces progres visent a une amelioration de la survie globale, des la premiere ligne de traitement, par l’obtention [...]