scholarly journals Quantitative Immunoprecipitation Free Light Chain Mass Spectrometry (QIP-FLC-MS) Simplifies Monoclonal Protein Assessment and Provides Added Clinical Value in Systemic AL Amyloidosis

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 4375-4375 ◽  
Author(s):  
Faye Amelia Sharpley ◽  
Hannah Victoria Giles ◽  
Richa Manwani ◽  
Shameem Mahmood ◽  
Sajitha Sachchithanantham ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Light Chain ◽  
Residual Disease ◽  
Renal Involvement ◽  
Light Chains ◽  
Al Amyloidosis ◽  
Free Light Chains ◽  
Accurate Identification ◽  
Monoclonal Protein ◽  
Serum And Urine

Introduction Early diagnosis, effective therapy and precise monitoring are central for improving clinical outcomes in systemic light chain (AL) amyloidosis. Diagnosis and disease response assessment is primarily based on the presence of monoclonal immunoglobulins and free light chains (FLC). The ideal goal of therapy associated with best outcomes is a complete responses (CR), defined by the absence of serological clonal markers. In both instances, detection of the monoclonal component (M-component) is based on serum FLC assessment together with traditional serum and urine electrophoretic approaches, which present inherent limitations and lack sensitivity particularly in AL where the levels are typically low. Novel mass spectrometry methods provide sensitive, accurate identification of the M-component and may prove instrumental in the timely management of patients with low-level amyloidogenic light chain production. Here we assess the performance of quantitative immunoprecipitation FLC mass spectrometry (QIP-FLC-MS) at diagnosis and during monitoring of AL amyloidosis patients treated with bortezomib-based regimens. Methods We included 46 serial patients with systemic AL amyloidosis diagnosed and treated at the UK National Amyloidosis Centre (UK-NAC). All patients had detailed baseline assessments of organ function and serum FLC measurements. Baseline, +6- and +12-month serum samples were retrospectively analysed by QIP-FLC-MS. Briefly, magnetic microparticles were covalently coated with modified polyclonal sheep antibodies monospecific for free kappa light chains (anti-free κ) and free lambda light chains (anti-free λ). The microparticles were incubated with patient sera, washed and treated with acetic acid (5% v/v) containing TCEP (20 mM) in order to elute FLC in monomeric form. Mass spectra were acquired on a MALDI-TOF-MS system (Bruker, GmbH). Results were compared to serum FLC measurements (Freelite®, The Binding Site Group Ltd), as well as electrophoretic assessment of serum and urine proteins (SPE, sIFE, UPE and uIFE). Results Cardiac (37(80%) patients) and renal (31(67%) patients) involvement were most common; 25(54%) patients presented with both. Other organs involved included liver (n=12), soft tissue (n=4), gastrointestinal tract (n=3) and peripheral nervous system (n=2). Baseline Freelite, SPE, sIFE and uIFE measurements identified a monoclonal protein in 42(91%), 22(48%), 34(74%) and 21(46%) patients, respectively. A panel consisting of Freelite + sIFE identified the M-component in 100% of the samples. QIP-FLC-MS alone also identified an M-component in 100% of the samples and was 100% concordant with Freelite for typing the monoclonal FLC (8 kappa, 34 lambda). In 4 patients, QIP-FLC-MS identified an additional M-protein that was not detected by the other techniques. In addition, 4/8(50%) kappa and 4/38(11%) lambda patients showed a glycosylation pattern of monoclonal FLCs at baseline by mass spectrometry. Interestingly, the frequency of renal involvement was significantly lower for patients with non-glycosylated forms (25% vs 76%, p=0.01), while no similar relationship was found for any other organs. During the 1-year follow-up period, 17 patients achieved a CR; QIP-FLC-MS identified serum residual disease in 13(76%) of these patients. Conclusion In our series, QIP-FLC-MS was concordant with current serum methods for identifying the amyloidogenic light chain type and provided, against all other individual tests, improved sensitivity for the detection of the monoclonal protein at diagnosis and during monitoring. The ability to measure the unique molecular mass of each monoclonal protein offers clone-specific tracking over time. Glycosylation of free light chains is over-represented in AL patients which may allow earlier diagnosis and better risk-assessment of organ involvement. Persistence of QIP-FLC-MS positive M component in patients otherwise in CR may allow targeted therapy. Overall, QIP-FLC-MS demonstrates potential to be exploited as a single serum test for precise serial assessment of monoclonal proteins in patients with AL amyloidosis. Disclosures Wechalekar: GSK: Honoraria; Janssen-Cilag: Honoraria; Amgen: Research Funding; Takeda: Honoraria; Celgene: Honoraria.

Free Light Chains, Monoclonal Proteins, and Chronic Lymphocytic Leukemia.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 4697-4697 ◽  
Author(s):  
Rosa Ruchlemer ◽  
Constantine Reinus ◽  
Esther Paz ◽  
Ahuva Cohen ◽  
Natalia Melnikov ◽  
...  
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Light Chain ◽  
Lymphocytic Leukemia ◽  
Light Chains ◽  
P Value ◽  
Advanced Stage ◽  
Free Light Chains ◽  
Monoclonal Protein ◽  
Low Levels ◽  
Monoclonal Proteins

Abstract Monoclonal proteins(MPs) can frequently be detected in the serum/urine of chronic lymphocytic leukemia(CLL) patients. Serum free light chains(FLC) assays can detect MPs in the absence of M bands on immunofixation(IMF).An abnormal FLC ratio indicates excess of one light chain type suggesting clonality.We evaluated fresh serum/urine samples from 34 CLL patients at various stages of disease by quantitative nephelometric assay,IMF and FLC assay.Median age was 66 yrs(43–87),M:F 1.9:1 and median time from diagnosis 41.5 mos(5–288). 45% had advanced stage and 39% prior treatment with 1–7 therapies.Only 2 patients had mild renal failure.Serum immunoglobulins were normal/low in 94% of patients:IgG (171–1580 mg/l, median 803 mg/l), IgA(<25–310 mg/l, median 88 mg/l),IgM(<18–290 mg/l, median 38 mg/l), irrespective of the presence of a monoclonal protein. 71% of patients had evidence of abnormal immunoglobulin synthesis: by IMF alone (8),IMF and FLC(10) or FLC alone(8).Abnormal FLC ratios were more frequently associated with advanced stage disease and increased κ chains(see table 1). Abnormal FLC ratios(< 0.26 or >1.65) were measured in 18(53%) patients, 8 of whom did not have MPs by IMF. Two advanced stage patients had abnormal FLC ratios due to very low levels of a single light chain, most probably reflecting secondary hypogammaglobulinemia due to CLL and/or chemotherapy.Abnormal FLC ratios reverted to normal after 1 course of chemotherapy(FC+/−R) in 3 patients despite persistence of minimal residual disease(MRD).FLC were of the same type as expressed on the surface of CLL cells, with discrepancies observed in 5 patients.BM biopsy staining for light chains revealed IgAκ MGUS in addition to λ chain restricted CLL in one patient, but was noncontributory in the other 4. Conclusions: Neither IMF nor the FLC assay alone could detect all MPs. Normal FLC ratios do not exclude the presence of MPs. The FLC ratio should be interpreted with caution in CLL patients with advanced disease and hypogammaglobulinemia. Monoclonal bands and abnormal FLC ratios can be detected despite normal or low levels of serum immunoglobulins in CLL patients. The significance of these monoclonal gammopathies in CLL is not clear and warrants further study in a larger group of patients. Discrepancies between surface immunoglobulins and serum/urine MPs might suggest the presence of an additional condition:ex. MGUS. FLC may not be a sensitive measure of MRD. Normal FLC ratio Abnormal FLC ratio P value *median No. patients 16(47%) 18(53%) M:F 1.3:1 3.5:1 NS Age* 62.5 yrs(49–73) 68 yrs(43–87) NS Time from CLL diagnosis* 25.3 mos(0–282) 59 mos(0–210) NS Adv stage(Rai III/IV-Binet C) 25% 66.7% 0.018 Untreated 62% 50% NS CLL:κ:λ restriction 7:8(0.88:1) 11:6(1.8:1) NS Monoclonal protein 8(50%) 10(56%) NS Increased freeκ no. 8 15 0.043 Freeκ level* 19.6(4.5–200) 39.2(2.9–386) 0.0064 Increased freeλ no 4 3 NS Free λ level* 19.3(12.4–146) 15.4(0.1–517) NS Serum β 2m* 3.1(1.8–6.7) 4.3(2.2–10.2) NS Zap70≥20 86% 36% 0.002 CD38≥30 44% 44% NS 17pdel/11qdel 40% 44% NS

A patient with AL amyloidosis with negative free light chain results

2016 ◽  
Vol 54 (6) ◽  
Author(s):  
Paolo Milani ◽  
Veronica Valentini ◽  
Giovanni Ferraro ◽  
Marco Basset ◽  
Francesca Russo ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Bone Marrow Biopsy ◽  
Light Chain ◽  
Left Ventricular ◽  
Free Light Chain ◽  
Response To Treatment ◽  
Light Chains ◽  
Al Amyloidosis ◽  
Light Chain Restriction ◽  
Serum And Urine

AbstractThe detection and quantification of amyloidogenic monoclonal light chains are necessary for the diagnosis and evaluation of response to treatment in AL amyloidosis. However, the amyloid clone is often small and difficult to detect. We report the case of a 68-year-old man who was referred to our Center in April 2013 after syncope and the identification of left ventricular hypertrophy at echocardiography, suspected for amyloidosis. A commercial agarose gel electrophoresis immunofixation (IFE) did not reveal monoclonal components in serum and urine. The κ serum free light chain (FLC) concentration was 21.5 mg/L, λ 33 mg/L (κ/λ ratio 0.65), NT-proBNP 9074 ng/L (u.r.l. <332 ng/L) and an echocardiogram confirmed characteristic features of amyloidosis. The abdominal fat aspiration was positive and the amyloid typing by immune-electron microscopy revealed λ light chains deposits. A high-resolution (hr) IFE of serum and urine showed a faint monoclonal λ component in the urine. A bone marrow biopsy showed 8% plasma cells (BMPC) and a kappa/lambda light-chain restriction with λ light chain on immunofluorescence. The diagnosis of AL (λ) amyloidosis with cardiac involvement was made. In May 2013, patient was started on cyclophosphamide, bortezomib and dexamethasone. After six cycles, serum and urine hr-IFE were negative, the bone marrow biopsy showed 3% BMPC without light chain restriction by immunofluorescence, and a decrease of NT-proBNP was observed (5802 ng/L).Thus, treatment was discontinued. In this patient the amyloid clone could be detected only by in house hr-IFE of urine and bone marrow examination. The detection of the small dangerous amyloidogenic clone should be pursued with a combination of high-sensitivity techniques, including assessment of BMPC clonality. Studies of novel tools, such as mass spectrometry on serum and next-generation flow cytometry analysis of the bone marrow, for detecting plasma cell clones in AL amyloidosis and other monoclonal light chain-related disorders are warranted.

Deposition of Lambda Chain Constant Region within AL-Amyloid Lesion

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 3348-3348
Author(s):  
Hiroyuki Hata ◽  
Masayoshi Tasaki ◽  
Konen Obayashi ◽  
Taro Yamashita ◽  
Yukio Ando ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Light Chain ◽  
Mass Spectrometry Analysis ◽  
Light Chains ◽  
High Dose ◽  
Al Amyloidosis ◽  
Constant Region ◽  
Rt Pcr ◽  
Immunoglobulin Light Chain ◽  
Lambda Light Chain

Abstract [Introduction] Diagnosis of AL amyloidosis is dependent on the proof of light chains in amyloid lesions. However, immunostaining does not always successfully prove the presence of light chains in lesions in AL amylidosis patients. Here we report that the constant region of immunoglobulin lambda light chain (IGLC2) is seen in amyloid lesions where no positive signals are found with regular immunostaining. [Materials and Methods] Amyloid samples were stained with anti-human lambda light chain antibody (DAKO PO-0130) and analyzed with mass-spectrometry combining laser micro-dissection. Bone marrow samples were obtained from patients with amyloidosis, who gave written informed consent, and were subjected to plasma cell purification using CD138-immunomagnetic beads. Expression of immunoglobulin light chain mRNA was examined with RT-PCR. Anti-human IGLL5 antibody, capable of detecting immunoglobulin light chain constant region 2 (IGLC2) in paraffin embedded samples, was utilized. [Results and Discussion] We performed immunostaining for immunoglobulin light chains with 18 samples and found that six and eight cases were positive for kappa and lambda light chains, respectively, whereas light chains were not detected in remaining four cases (immunostaining-negative amyloidosis; INA). However, interestingly, mass spectrometry analysis revealed the presence of IGLC2 in all of the INA cases. RT-PCR analysis revealed the presence of IGLC2 mRNA in plasma cells from such INA cases. Surprisingly, amyloid lesions in all of the INA cases were positively stained with anti-IGLL5 antibody, whereas no staining was found in other samples positively stained with DAKO PO-0130. These observations suggest that the deposition of IGLC2 may cause AL amyloidosis, which otherwise could not be diagnosed with regular immunostaining. Although high dose chemotherapy produced hematological remission, half of such cases died within one year, suggesting irreversible and life-threatening amyloid fibril depositions in critical organs in IGLC2-related cases. We further examined additional twelve cases with AL amyloidosis to determine the incidence of IGLC2-related amyloidosis by immunostaining. With regular immunostaining, kappa and lambda chain were found in three and five cases, respectively. Interestingly, the remaining four cases were negative with regular immunostaining but positive with anti-IGLL5 antibody. Taken these observations together, eight IGLC2-related amyloidosis cases and thirteen lambda type amyloidosis were identified. Thus, the incidence of IGLC2-related amyloidosis should be approximately 38% (8/21) among lambda type AL amyloidosis. We conclude that diagnosis of IGLC2-related AL amyloidosis was possible only with the use of anti-IGLL5 antibody, but not with regular immunostaining. Given the relatively high incidence and often poor prognosis of IGLC2-related amyloidosis, it is important that this clinical entity is recognized to potentially improve outcomes of treatments. Analysis of mechanisms regulating amyloid formation with IGLC2 peptides is currently underway. Disclosures No relevant conflicts of interest to declare.

scholarly journals Identification of Amyloidogenic Light Chains Requires the Combination of Serum-Free Light Chain Assay with Immunofixation of Serum and Urine

2009 ◽  
Vol 55 (3) ◽  
pp. 499-504 ◽  
Author(s):  
Giovanni Palladini ◽  
Paola Russo ◽  
Tiziana Bosoni ◽  
Laura Verga ◽  
Gabriele Sarais ◽  
...  
Keyword(s):  
Light Chain ◽  
Gel Electrophoresis ◽  
Light Chains ◽  
Al Amyloidosis ◽  
Agarose Gel ◽  
Agarose Gel Electrophoresis ◽  
Serum Free ◽  
Serum Free Light Chain ◽  
Amyloid Deposits ◽  
Serum And Urine

Abstract Background: The diagnosis of systemic immunoglobulin light-chain (AL) amyloidosis requires demonstration of amyloid deposits in a tissue biopsy and amyloidogenic monoclonal light chains. The optimal strategy to identify the amyloidogenic clone has not been established. We prospectively assessed the diagnostic sensitivity of the serum free light chain (FLC) κ/λ ratio, a commercial serum and urine agarose gel electrophoresis immunofixation (IFE), and the high-resolution agarose gel electrophoresis immunofixation (HR-IFE) developed at our referral center in patients with AL amyloidosis, in whom the amyloidogenic light chain was unequivocally identified in the amyloid deposits. Methods: The amyloidogenic light chain was identified in 121 consecutive patients with AL amyloidosis by immunoelectron microscopy analysis of abdominal fat aspirates and/or organ biopsies. We characterized the monoclonal light chain by using IFE and HR-IFE in serum and urine and the FLC κ/λ ratio in serum. We then compared the diagnostic sensitivities of the 3 assays. Results: The HR-IFE of serum and urine identified the amyloidogenic light chain in all 115 patients with a monoclonal gammopathy. Six patients with a biclonal gammopathy were omitted from the statistical analysis. The diagnostic sensitivity of commercial serum and urine IFE was greater than that of the FLC κ/λ ratio (96% vs 76%). The combination of serum IFE and the FLC assay detected the amyloidogenic light chain in 96% of patients. The combination of IFE of both serum and urine with the FLC κ/λ ratio had a 100% sensitivity. Conclusions: The identification of amyloidogenic light chains cannot rely on a single test and requires the combination of a commercially available FLC assay with immunofixation of both serum and urine.

scholarly journals A Novel Mass Spectrometry Method to Identify the Serum Monoclonal Light Chain Component and Infer Organ Involvement in Systemic Light Chain Amyloidosis

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 4445-4445 ◽  
Author(s):  
Faye Sharpley ◽  
Richa Manwani ◽  
Shameem Mahmood ◽  
Sajitha Sachchithanantham ◽  
Helen Lachmann ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Molecular Mass ◽  
Light Chain ◽  
Mass Spectra ◽  
Amyloid Fibrils ◽  
Cardiac Involvement ◽  
Small Sample ◽  
Organ Involvement ◽  
Light Chains ◽  
Al Amyloidosis

Abstract Introduction Light chain (AL) amyloidosis is caused by progressive organ dysfunction due to the deposition of structurally abnormal monoclonal light chains (LC) as amyloid fibrils. Serial free light chain measurement is the cornerstone of AL diagnosis but is limited by current methods which measure normal polyclonal and abnormal monoclonal LCs. Since each individual monoclonal LC has a unique amino acid sequence, mass spectrometry (MS) has the ability to detect serum monoclonal LCs. We report a novel MS method for monoclonal LC detection in AL amyloidosis. Methods Twenty patients with systemic AL amyloidosis, diagnosed and treated at the UK National Amyloidosis Centre (UK-NAC), were randomly selected. This included 16 newly diagnosed patients, 2 patients in a complete haematological remission (CR) post-treatment and 2 patients with no amyloidosis (acting as negative controls). All patients had detailed baseline assessments of organ function and serum FLC measurements. Organ involvement was defined according to the international amyloidosis consensus criteria. Magnetic microparticles were covalently coated with modified polyclonal sheep antibodies monospecific for free kappa light chains (anti-free k) and free lambda light chains (anti-free l). The microparticles were incubated with patient sera, washed and treated with acetic acid (5% v/v) containing TCEP (20 mM) in order to elute free light chains in monomeric form. Mass spectra were acquired on a Microflex LT/SH smart matrix-assisted laser desorption ionization time-of-flight mass spectrometer (MALDI-TOF-MS; Bruker, GmbH). Results The median number of organs involved was 2 (range 1-4); cardiac involvement was most common in 70% (14/20) patients, followed by renal 40% (8/20), autonomic and soft tissue in 15% (3/20) and peripheral nerve involvement in 5% (1/20). No patients had liver involvement. The median N-terminal pro b-type natriuretic peptide (NT-proBNP) and cardiac troponin T were 3761.5 (range 245-25348 ng/L) and 35.5 (8-170 ng/L) respectively. The median presenting serum albumin was 37 (19-45 g/L) and eGFR 62 (10-100 mls/min). The amyloid deposits were typed as AL lambda in 14(70%), kappa in 2(10%) patients and amyloid of uncertain type in two cases (10%). The median involved FLC was kappa 76 mg/L (range 71-440) and lambda 185 mg/L (44-1023), with difference involved to uninvolved (dFLC) 118 mg/L (33-1015). An intact monoclonal protein was present in 70% (14/20). In all cases, MS correctly identified the presence and type of monoclonal LC, identifying a monoclonal lambda in 14/14 (100%) and a monoclonal kappa in 2/2 (100%); the two patients where a clear monoclonal component could not be identified were patients whose amyloid fibrils failed to be typed by immunohistochemistry or MS. The assay also confirmed normal polyclonal expression of both kappa and lambda LCs in the two control samples. In the two lambda patients in a CR, the MS method identified monoclonal lambda LC expression; in one of these patients next-generation sequencing (NGS) confirmed minimal residual disease (MRD). A clear shift in the LC mass spectra was seen relating to the specific pattern of organ involvement: in patients with renal amyloid the monoclonal LC predominantly displayed a "heavy" molecular mass, (with a mean molecular mass of 11596+/- 436 daltons), whereas in patients with cardiac involvement the monoclonal LC mainly exhibited a "light" mass (with a mean molecular mass of 11443 +/- 102 daltons). Conclusion This small study shows that monoclonal light chains can be accurately detected by MS and be concordant to the tissue amyloid type. A monoclonal LC was detected in 2 patients in serological "CR" - in one case presence of persistent disease was demonstrated by NGS-MRD. Even in this small sample size, there appears to be a marked difference in LC mass for patients with cardiac ("light" LC) vs. renal ("heavy" LC) involvement, raising the interesting possibility that "heavy" LC are trapped by the glomerulus causing renal AL but are unable to penetrate the tight cardiac capillary gap junctions, and vice versa. The unique molecular location of LC on MS offers the possibility of exploiting this technique as a tool to detect amyloidogenic FLC and potentially predict organ involvement in patients with gammopathies. We plan to expand this study to a large cohort of patients to confirm these findings and assess the impact on survival and organ response outcomes. Figure 1 Figure 1. Disclosures Wechalekar: Janssen: Honoraria.

scholarly journals Clinical Presentation and Outcomes of Patients with Light Chain Amyloidosis Who Have Non-Evaluable Free Light Chains at Diagnosis

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 3272-3272
Author(s):  
Surbhi Sidana ◽  
Nidhi Tandon ◽  
Angela Dispenzieri ◽  
Morie A. Gertz ◽  
Francis K Buadi ◽  
...  
Keyword(s):  
Partial Response ◽  
Board Of Directors ◽  
Light Chain ◽  
Research Funding ◽  
Cardiac Involvement ◽  
Renal Involvement ◽  
Light Chains ◽  
Free Light Chains ◽  
Advisory Committees

Abstract Introduction: Hematologic response criteria for light chain amyloidosis (AL) requires that difference in involved and uninvolved free light chains (dFLC) be at least 5 mg/dL (or 50 mg/L). However, many patients do not meet these criteria and are often excluded from clinical trials. These patients are challenging to follow clinically as organ response takes much longer and therefore response to treatment is difficult to evaluate in the first few cycles. This study aims to evaluate patients who had non-evaluable FLC (dFLC< 5 mg/dL) at diagnosis and compare them to those who had evaluable FLC (dFLC≥ 5 mg/dL). Methods: All patients with newly diagnosed AL seen within 90 days of diagnosis at our institution over a 10-year period (2006-2015) were identified from an institutional database. Data pertaining to demographics, diagnosis, treatment and follow-up was extracted from electronic medical records. Analysis was carried out by chi-square and Fisher's exact test for categorical variables and Kruskal-Wallis and Wilcoxon rank sum test for ordinal and continuous variables. Progression free survival (PFS) is defined as time to progression requiring treatment change or relapse requiring re-institution of treatment or death. PFS and overall survival (OS) were analyzed via the Kaplan-Meier method. Results: Of 1336 patients meeting inclusion criteria, dFLC at diagnosis was known in 1290. 85.4% (n=1101) had dFLC ≥ 5 mg/dL, while 14.6% (n=189) had non-evaluable FLC. Median age at diagnosis (65.2 vs. 63.9 years), gender distribution (males 56.1% vs.64.8%) and involved FLC (lambda: 72.2% vs. 72.9%) was similar in FLC < 5 mg/dL and FLC ≥ 5 mg/dL group. Cardiac (38.1 vs. 76.3%, p <0.0001) and liver (10.2% vs. 16.3%, p=0.03) organ involvement were less common in patients with non-evaluable FLC (table 1). NT-ProBNP was significantly lower in the group with dFLC < 5 mg/dL in patients with and without cardiac involvement, as was Mayo cardiac stage (table 1). A trend towards less gastrointestinal (GI) involvement (17.1% vs. 24%, p=0.09) was also seen with dFLC < 5 mg/dL. In contrast, a trend towards higher renal involvement was seen in patients with dFLC < 5 mg/dL (64.6% vs. 55.9%, p=0.08), though this was not statistically significant. Median 24 hour urine protein was significantly higher in all patients (with and without renal involvement) with dFLC < 5 mg/dL compared to dFLC ≥ 5 mg/dL group (table 1). Treatment details are listed in Table 1. ASCT (autologous stem cell transplant) was utilized more commonly in patients with dFLC < 5 mg/dL compared to patients with dFLC ≥ 5 mg/dL(43.2% vs. 26.1%, p <0.0001), including ASCT alone without chemotherapy (35.4% vs. 15.3%, p <0.0001).Rates of cardiac response (53.3% vs. 50.3%, p=0.88), and time to response (27.7 weeks vs. 35.6 weeks, p=0.67), were similar in both groups. Similarly, there was no difference in rates of renal and liver response and time taken to achieve a response (table 1). In patients with evaluable FLC, hematologic response was complete response (27.3%, n=245), very good partial response (21%, n=189), partial response (18%, n=160), no response (8%, n=74), progression (2%, n=15) and not known in 26.1% (n=216). In patients who had follow up data available, 30.6% (44/144) with dFLC < 5mg/dL experienced a relapse/progression with median PFS of 4.1 years (95% confidence interval (CI): 3 to 5.7), while 34.7% (304/875) with FLC ≥ 5 mg/dL experienced a relapse/progression with median PFS of 1.3 years (95% CI 1.1 to 1.5); p<0.0001. Median OS was higher in patients with dFLC < 5 mg/dL at diagnosis at 8.3 years compared to 2.4 years in patients with dFLC ≥ 5 mg/dL (p < 0.0001) as depicted in Figure 1. Conclusions: Patients with non-evaluable FLC at diagnosis have significant differences in organ involvement and survival compared to those with FLC ≥ 5 mg/dL at diagnosis. They have less cardiac and liver involvement and a trend towards less GI involvement, which may be secondary to low serum FLC burden and consequent less organ deposition. However, a trend towards higher renal involvement was seen in dFLC < 5 mg/dL group, with significantly higher urinary protein excretion. Loss of FLC in urine may result in lower serum FLC levels in this group. Survival was significantly better in patients with dFLC < 5 mg/dL, which may be explained by less cardiac involvement, lower cardiac stage and lower median FLC at diagnosis. Disclosures Dispenzieri: GSK: Membership on an entity's Board of Directors or advisory committees; Prothena: Membership on an entity's Board of Directors or advisory committees; pfizer: Research Funding; Celgene: Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees, Research Funding; Alnylam: Research Funding; Jannsen: Research Funding. Kapoor:Amgen: Research Funding; Takeda: Research Funding; Celgene: Research Funding. Kumar:Celgene: Consultancy, Research Funding; Janssen: Research Funding; Sanofi: Consultancy, Research Funding; Skyline: Consultancy, Honoraria; BMS: Consultancy; AbbVie: Research Funding; Noxxon: Consultancy, Honoraria; Amgen: Consultancy, Research Funding; Takeda: Consultancy, Research Funding.

IgD Amyloidosis: An Unrecognized Entity

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 5079-5079
Author(s):  
Morie Abraham Gertz ◽  
Francis K Buadi ◽  
Suzanne R Hayman ◽  
David Dingli ◽  
Angela Dispenzieri ◽  
...  
Keyword(s):  
Light Chain ◽  
Conflicts Of Interest ◽  
Demographic Data ◽  
Performance Status ◽  
Renal Involvement ◽  
Renal Amyloidosis ◽  
Al Amyloidosis ◽  
Liver Size ◽  
Monoclonal Protein ◽  
Monoclonal Proteins

Abstract 5079 Introduction: IgD monoclonal proteins are rare. They are not seen as a MGUS and are present in 1% to 2% of patients with myeloma. In light chain amyloidosis (AL), IgD monoclonal proteins are rare. When an IgD protein is found, amyloidosis is often omitted from the differential diagnosis. An IgD protein in amyloidosis has been reported in single cases but never as a patient series. We report IgD AL in 53. Patients & Methods: Clinical and demographic data for patients were retrieved from the patient records. Factors of interest were compared between patients who did and did not have an IgD protein. Results: Among 3,955 patients with AL amyloidosis seen, 53 patients (1.3%) had a serum IgD monoclonal protein. (Table 1) A serum monoclonal protein peak was visible on SPE in only 14, and only 5 had an M spike greater than 1 g/dL. On immunofixation of the serum, the IgD light chain was k in 11, λ in 35, and uncertain in 6; 1 patient had a biclonal D λ and G k protein. A urine monoclonal protein was detected in 43 of 51 patients; urinary immunofixation detected a λ light chain in 33 and a k light chain in 10. Biopsy of tissues showed amyloid deposits in the bone marrow in 47% and in the fat aspirate in 73%. Six patients (age 47–63 years) underwent autologous SCT. Four had renal & two had cardiac AL. All 6 had hematologic PR, 4 CR, and 4 had organ response. One patient had relapse of disease and is now on dialysis, and another had relapse and is alive with salvage chemotherapy. One patient had disease relapse and died of progressive GI amyloidosis at 22 months. The other 5 are alive at a median of 68 months (range, 7.5–83.5 months). We compared the 53 patients with IgD amyloidosis with 144 patients with non-IgD amyloidosis. (Table 2) Findings that were significantly different between groups included a lower frequency of renal amyloidosis (P=.005) and a lower prevalence of cardiac amyloidosis (P=.047). There was a higher serum albumin level (P=.04) related to the lower level of proteinuria. No difference in survival was seen between the groups. (Figure). Variables that might affect survival—liver size, performance status, septal thickness, serum creatinine level, and β2-microglobulin level—were not different between groups. Conclusions: IgD AL patients have a lower frequency of renal involvement and possibly also of cardiac involvement. The overall survival of these patients does not appear to be different from that of patients who have AL associated with another monoclonal protein. IgD monoclonal proteins are so closely linked to the diagnosis of multiple myeloma in the mind of a clinician that the possibility of amyloidosis may be overlooked. Disclosures: No relevant conflicts of interest to declare.

Monitoring free light chains in serum using mass spectrometry

2016 ◽  
Vol 54 (6) ◽  
Author(s):  
David R. Barnidge ◽  
Angela Dispenzieri ◽  
Giampaolo Merlini ◽  
Jerry A. Katzmann ◽  
David L. Murray
Keyword(s):  
Mass Spectrometry ◽  
Light Chain ◽  
Disulfide Bonds ◽  
Plasma Cells ◽  
Mass Measurement ◽  
Normal Serum ◽  
High Mass ◽  
Light Chains ◽  
Plasma Cell Dyscrasia ◽  
Free Light Chains

AbstractSerum immunoglobulin free light chains (FLC) are secreted into circulation by plasma cells as a by-product of immunoglobulin production. In a healthy individual the population of FLC is polyclonal as no single cell is secreting more FLC than the total immunoglobulin secreting cell population. In a person with a plasma cell dyscrasia, such as multiple myeloma (MM) or light chain amyloidosis (AL), a clonal population of plasma cells secretes a monoclonal light chain at a concentration above the normal polyclonal background.We recently showed that monoclonal immunoglobulin rapid accurate mass measurement (miRAMM) can be used to identify and quantify a monoclonal light chain (LC) in serum and urine above the polyclonal background. This was accomplished by reducing immunoglobulin disulfide bonds releasing the LC to be analyzed by microLC-ESI-Q-TOF mass spectrometry. Here we demonstrate that the methodology can also be applied to the detection and quantification of FLC by analyzing a non-reduced sample.Proof of concept experiments were performed using purified FLC spiked into normal serum to assess linearity and precision. In addition, a cohort of 27 patients with AL was analyzed and miRAMM was able to detect a monoclonal FLC in 23 of the 27 patients that had abnormal FLC values by immunonephelometry.The high resolution and high mass measurement accuracy provided by the mass spectrometry based methodology eliminates the need for κ/λ ratios as the method can quantitatively monitor the abundance of the κ and λ polyclonal background at the same time it measures the monoclonal FLC.

scholarly journals Comparison of lambda and kappa light-chain cardiac amyloidosis in Polish patients diagnosed in cardiology department

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
J.A Szczygiel ◽  
P Michalek ◽  
J Drozd-Sokolowska ◽  
M Ziarkiewicz ◽  
Z.T Bilinska ◽  
...  
Keyword(s):  
Light Chain ◽  
Cardiac Amyloidosis ◽  
Light Chains ◽  
Al Amyloidosis ◽  
Free Light Chains ◽  
Lambda Light Chain ◽  
Serum Free ◽  
Kaplan Meier ◽  
Cardiology Department ◽  
Serum Free Light Chains

Abstract Background Lambda (λ) and kappa (κ) types of light-chain amyloidosis (AL amyloidosis) are believed to have a similar prognosis. Data on the comparison of these two types of cardiac amyloidosis is scanty. Objectives The aim of the study was to investigate wether lambda light-chain cardiac amyloidosis indicates worse prognosis than the kappa variety. Methods The initial analysis covered all consecutive pts with cardiac AL amyloidosis diagnosed in the cardiology department from August 2011 to August 2019. Diagnosis was confirmed by increased serum free light-chains and positive tissue biopsy. Amyloid type was identified using immunohistochemical reactions. Blood pressure and heart rate (HR) were measured on admission. The difference between involved and uninvolved serum free light chains (dFLC), NT-proBNP, high-sensitivity troponin T (hs-TnT), creatinine, potassium, albumin and total protein were measured. During echocardiography, tissue Doppler imaging was used to assess early lateral (e' lat) and septal mitral annulus velocities and longitudinal myocardial velocities of ventricles. Standard parameters were measured. The presence of pleural effusion was assessed in chest X-ray. Results Sixty-four pts were diagnosed with AL amyloidosis. Four pts were excluded from the final analysis due to ambiguous amyloid typing. Median (interquartile range, IQR) age was 61 (52–67) yrs. Median (IQR) dFLC was 19.9 (5.5–50.6) mg/dL. Median NT-proBNP and hs-TnT concentrations were 4948 (2251–10206) pg/ml and 77 (39–139) ng/l, respectively. Forty-four pts had a λ type AL amyloidosis (73.3%). There were significant differences (p&lt;0.05) between the λ and the κ groups in regard to: HR (80 vs. 73.5 BPM), systolic blood pressure (102 vs. 117 mmHg), serum creatinine (88 vs. 116 umol/L) and potassium (4.4 vs. 4.9 mmol/L), e' lat (5 vs. 7.5 cm/sec), left ventricular end-diastolic diameter (LVEDD, 42 vs. 46 mm), right ventricular end-diastolic diameter (RVEDD, 35 vs. 40 mm) and right ventricular wall thickness (8 vs. 6 mm). Pleural and pericardial effusions were more frequent in the λ group (59% vs. 19% and 80% vs. 44%, respectively) according to Fisher's exact test (p&lt;0.05). Median (IQR) survivals for the λ and the κ groups were 3 (2–9) and 16 (5.5–22) months, respectively (p=0.03). The Kaplan-Meier curves analysis showed a trend towards worse survival of the λ group (Log rank test, p=0.08). Conclusions Cardiologists should be aware that lambda light-chain cardiac amyloidosis may indicate shorter survival than the kappa variety, although kappa AL amyloidosis may be associated with worse kidney function. Further research would be worth considering. Kaplan-Meier curves, Time (months) Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): Institute of Cardiology

scholarly journals Light chain myeloma and detection of free light chains in serum and urine of dogs and cats

2021 ◽  
Author(s):  
Robert Adam Harris ◽  
Matthew Miller ◽  
Dillon Donaghy ◽  
Laura Ashton ◽  
Catherine Langston ◽  
...  
Keyword(s):  
Light Chain ◽  
Light Chains ◽  
Free Light Chains ◽  
Serum And Urine
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