Serum Immunofixation Research Articles

Hypercalcaemia, Renal Dysfunction, Anaemia, Bone Disease (CRAB Criteria): A Case of Lymphoma

The CRAB criteria consist of end-organ damage with hypercalcaemia, renal dysfunction, anaemia and bone involvement.The CRAB criteria are not pathognomonic of multiple myeloma, and in the appropriate clinical scenario, lymphoma is a possible diagnosis.Major mechanisms by which hypercalcaemia of malignancy can occur are tumour secretion of parathyroid hormone-related protein (PTHrP), osteolytic metastases with local release of cytokines, or tumour production of 1,25-dihydroxyvitamin D (calcitriol).

Retrospective evaluation of the use of the International Myeloma Working Group response criteria in dogs with secretory multiple myeloma.

BackgroundCurrent recommendations for monitoring disease progression and response to treatment in humans with multiple myeloma include evaluation of serum paraprotein (M‐protein) concentration. Densitometry, species‐specific radial immunodiffusion (RID) and ELISA methods can be used to quantify M‐proteins.ObjectiveRetrospectively evaluate use of the International Myeloma Working Group (IMWG) response criteria for humans in dogs with multiple myeloma.AnimalsSixteen dogs with a diagnosis of multiple myeloma, M‐protein documented by serum protein electrophoresis (SPE) and immunofixation (IF) in an initial sample and subsequent electrophoretic evaluation of serial samples.MethodsRetrospectively, densitometric M‐proteins, RID and globulins were measured and characterized according to IMWG criteria. Available clinical history was reviewed. Overall survival time (OST) was calculated from initial electrophoretic evaluation to death or last contact.ResultsAll cases received some form of nonstandardized chemotherapy. Complete response (CR), a lack of detectable M‐protein by SPE and IF, was documented in 1 case. Median survival was longer for dogs that attained ≥90% densitometric M‐protein reduction (630 days) than for those that did not attain at least 50% reduction in densitometric M‐protein (284 days; log rank P = .006). Five dogs were defined as having progressive disease (M‐protein increase of >25% and at least 0.5 g/dL from nadir), which correlated with concurrent or subsequent clinical deterioration. Response criteria categorized by serum globulins or RID was not correlated with OST or clinical findings.Conclusions and Clinical ImportanceDensitometric M‐protein characterized using IMWG response criteria correlated with OST and clinical findings. Densitometric M‐protein detection should be used to monitor dogs with multiple myeloma.

Diagnosing Transthyretin Cardiac Amyloidosis by Technetium Tc 99m Pyrophosphate: A Test in Evolution

ObjectivesThis study aimed to characterize trends in technetium Tc 99m pyrophosphate (99mTc-PYP) scanning for amyloid transthyretin cardiac amyloidosis (ATTR-CA) diagnosis, to determine whether patients underwent appropriate assessment with monoclonal protein and genetic testing, to evaluate use of single-photon emission computed tomography (SPECT) in addition to planar imaging, and to identify predictive factors for ATTR-CA. Background99mTc-PYP scintigraphy has been repurposed for noninvasive diagnosis of ATTR-CA. Increasing use of 99mTc-PYP can facilitate identification of ATTR-CA, but appropriate use is critical for accurate diagnosis in an era of high-cost targeted therapeutics. MethodsPatients undergoing 99mTc-PYP scanning 1 h after injection at a quaternary care center from 2010 to 2019 were analyzed; clinical information was abstracted; and SPECT results were analyzed. ResultsOver the decade, endomyocardial biopsy rates remained stable with scanning rates peaking at 132 in 2019 (p < 0.001). Among 753 patients (516 men, mean age 77 years), 307 (41%) had a visual score of 0, 177 (23%) of 1, and 269 (36%) of 2 or 3. Of 751 patients with analyzable heart to contralateral chest ratios, 249 (33%) had a ratio ≥1.5. Monoclonal protein testing status was assessed in 550 patients, of these, 174 (32%) did not undergo both serum immunofixation and serum free light chain analysis tests, and 331 (60%) did not undergo all 3 tests—serum immunofixation, serum free light chain analysis, and urine protein electrophoresis. Of 196 patients with confirmed ATTR-CA, 143 (73%) had genetic testing for transthyretin mutations. In 103 patients undergoing cardiac biopsy, grades 2 and 3 99mTc-PYP had sensitivity of 94% and specificity of 89% for ATTR-CA with 100% specificity for grade 3 scans. With respect to SPECT as a reference standard, planar imaging had false positive results in 16 of 25 (64%) grade 2 scans. ConclusionsUse of noninvasive testing with 99mTc-PYP scanning for evaluation of ATTR-CA is increasing, and the inclusion of monoclonal protein testing and SPECT imaging is crucial to rule out amyloid light chain amyloidosis and distinguish myocardial retention from blood pooling.

Baseline correlations and prognostic impact of serum monoclonal proteins in follicular lymphoma.

The presence of a serum monoclonal component has been associated with poor outcomes in some lymphomas. However, data in follicular lymphoma (FL) are scarce. We studied 311 FL patients diagnosed at a single institution, for whom information on serum immunofixation electrophoresis (sIFE) at diagnosis was available. Baseline characteristics and outcomes were compared between patients with a positive (+sIFE) and a negative sIFE (-sIFE). sIFE was positive in 82 patients (26%). Baseline features were comparable between both groups, except for an older age and higher proportion of elevated β2 -microglobulin levels in the +sIFE group. With a median follow-up of 4.6years, a +sIFE was associated with a higher risk of early relapse (POD24, 27% vs. 15%, P=0·02), shorter progression-free survival (PFS; 42% vs. 52% at 5years, P=0·008), and shorter overall survival (OS; 59% vs. 77% at 10years, P=0·046). In patients >60years, a +sIFE was an independent predictor of OS [hazard ratio (HR)=2·4, 95% confidence interval (CI): 1·2-5·0; P=0·02]. Approximately one quarter of patients with FL has a +sIFE at diagnosis, which is a predictor of poor outcome. These findings encourage further investigation of its relationship with B-cell biology and the tumour microenvironment.

Delayed diagnosis of Angioimmunoblast T-cell lymphoma presenting with type II Cryoglobulinemia and acute kidney injury: a case report and narrative review of the literature

BackgroundAngioimmunoblastic T cell lymphoma (AITL) is an infrequent hematological malignancy with variable and often atypical presentations. The presence of dysproteinemia, autoantibodies and systemic involvement in AITL has often led to a delay in diagnosis or even misdiagnosis in practice. We herewith present a case of AITL that primarily presented with acute kidney injury associated with type II Cryoglobulinemia, the underlying cause was only identified 8 months after the emergence of initial symptoms.Case presentationA 67-year old woman presented with 2-month history of intermittent joint pain and a 3-day history of bilateral lower limb edema and acute kidney injury. Initial laboratory investigations showed marked hypocomplementemia with positive autoantibodies of ANA, anti-cardiolipin-IgM and direct antiglobulin. The serum and urinary Immunofixation and serum cryoglobulin tests were negative, while the serum free κ to λ light chain ratio was 0.231. A renal biopsy showed a diffuse proliferative glomerulonephritis with intracapillary pseudothrombi formation. There were orderly arranged microtubular structures of 20–35 nm in diameter in the subendothelial and mesangial area on electron microscopy. Shortly afterwards, the patient developed tingling affecting her finger tips and weak hands and legs. A diagnosis of cryoglobulinemia complicated with cryoglobulinemic glomerulonephritis and polyneuropathy was made. She responded well to methylprednisolone, plasma exchange and rituximab. However, 3 months later, she presented with generalized pruritic rash, weight loss, and inguinal lymphadenopathy. A subsequent inguinal excisional lymph node biopsy at month 8 revealed AITL as the underlying disease.ConclusionsAITL and its associated B cell dysregulation can give rise to autoimmunity and cryoglobulinemia which may conceal itself as the underlying disorder. In various clinical scenarios of auto-immune diseases, it is advisable that the clinicians should take into consideration the multi-faceted lymphoma.

Short Daratumumab Consolidation in Patients with AL Amyloidosis or Lcdd Improves Complete Response Rates and Modifies Bone Marrow Microenvironment

Short Daratumumab Consolidation in Patients with AL Amyloidosis or Lcdd Improves Complete Response Rates and Modifies Bone Marrow Microenvironment

Light Chain Deposition Disease: First Analysis of an International Study in 359 Patients

Introduction: Light chain deposition disease (LCDD) is a rare complication of monoclonal gammopathies, defined by non-amyloid linear monoclonal light chain (most commonly kappa) deposits in the kidney and other organs. The rarity of LCDD has hampered clinical studies and staging systems and response criteria are lacking. The International Kidney Myeloma Working Group (IKMG) started a clinical data collection from all participating centers in order to define the natural history of LCDD, and to establish prognostic factors and response criteria in a large, international, unselected patient population. Methods: Eight referral centers have yet participated in the data collection at the data lock of July 31, 2020. Patient inclusion is ongoing and expected accrual is 500 patients. The diagnosis of LCDD had to be biopsy-proven. The patients were diagnosed between 1992 to 2020. Response was assessed 6 months after treatment initiation according to the criteria used in light chain (AL) amyloidosis. Renal survival (RS) was defined as time from diagnosis to dialysis or last follow-up. Patients who died without requiring dialysis were censored at the time of death. The analysis of factors predicting RS was performed in patients whose baseline estimated glomerular filtration rate (eGFR) was &amp;gt;15 mL/min. The cutoffs of baseline variables, as well as the cutoffs measured at the time of response, best predicting RS or OS at 12 months were identified by means of Receiver Operator Characteristics (ROC) analyses. All patients gave written informed consent for their clinical data to be used for research purposes. Results: Overall, 359 patients have been included in this first analysis. Sixteen (4%) subjects had concomitant cast nephropathy. The main clinical characteristics are reported in the Table. Median overall survival (OS) was 13 years and RS was 12 years (Figure1 A and 1B) and median survival of living patients is 4.5 years. At univariate analysis the only baseline variables predicting RS were proteinuria [best cutoff 2.5 g/24h, HR 2.25 (95%CI 1.13-4.60), P=0.02], and eGFR [best cutoff &amp;gt;30 mL/min, HR 0.50 (95%CI 0.26-0.96) P=0.037], but at multivariate analysis only proteinuria predicted RS [HR 2.17 (95% CI 1.08, 4.33), P=0.027]. At univariate analysis, a higher bone marrow plasma cell infiltrate (best cutoff ≥20%) at diagnosis was associated with a significantly lower OS [HR 1.96 (95% CI 1.23-3.13) P=0.004], as was having end stage renal disease (ESRD) defined as an eGFR &amp;lt;15 mL/min [HR 1.81 (95%CI 1.11-2.92) P=0.015]. We then tested the ability of the hematologic response criteria for AL amyloidosis to discriminate groups with different survival after treatment in a 6 months landmark analysis. Our choice of adopting the amyloidosis response criteria was corroborated by the results of the ROC analysis showing that the difference between involved and uninvolved free light chains (dFLC) cutoff (40 mg/L) used in AL amyloidosis to define very good partial response (VGPR) had 87% sensitivity and 65% specificity in identifying patients who needed dialysis within 12 months. Partial response (PR, 19% requiring dialysis at 3 years) was not associated with a RS benefit over no-response (29% requiring dialysis at 3 years, P=0.511). However, VGPR conferred a significant RS advantage (10% requiring dialysis at 3 years) over PR (P=0.002). No significant difference in RS was seen between complete response (CR, 0% requiring dialysis at 3 years) and VGPR (P=0.178). Thus, achieving VGPR or CR by amyloidosis response criteria [post-treatment dFLC&amp;lt;40 mg/L (VGPR by AL criteria), with or without negative serum and urine immunofixation and normal FLC-ratio (CR by AL criteria)] was adopted as a provisional criterion for hematologic response in LCDD (Figure 1D). LCDD response was also associated with prolonged OS (Figure 1C). Conclusions: Almost one-third of patients with LCDD are diagnosed when they already have ESRD resulting in shorter OS. The degree of proteinuria and of bone marrow plasma cell infiltration predict RS and OS, respectively. Achievement of post treatment dFLC &amp;lt;40 mg/L or negative serum and urine immunofixation at 6 months is proposed as a provisional criterion for hematologic response, being able to predict both improved RS and OS. Planned expanded recruitment might allow a validation analysis of the results, the analysis of organ response data and the evaluation of different time-points for response assessment. Disclosures Milani: Celgene: Other: Travel support; Janssen: Other: Speaker honoraria; Pfizer: Other: Speaker honoraria. Kastritis:Pfizer: Consultancy, Honoraria; Janssen: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria; Amgen: Consultancy, Honoraria, Research Funding; Genesis Pharma: Consultancy, Honoraria. Schönland:Janssen, Prothena, Takeda: Honoraria, Other: travel support to meetings, Research Funding. Bridoux:Baxter: Consultancy; Janssen: Honoraria; Celgene: Honoraria. Tuchman:Celgene: Honoraria, Research Funding, Speakers Bureau; Oncopeptides: Consultancy; Amgen: Research Funding; Caelum: Honoraria; Sanofi: Honoraria, Research Funding; Janssen: Research Funding; Roche: Research Funding; Karyopharm: Honoraria, Research Funding. Jimenez-Zepeda:Janssen, Celgene, Amgen, Takeda: Honoraria. Palladini:Jannsen Cilag: Honoraria, Other; Celgene: Other: Travel support. Wechalekar:Celgene: Honoraria; Caelum: Other: Advisory; Janssen: Honoraria, Other: Advisory; Takeda: Honoraria, Other: Travel.

Depth of Response and Response Kinetics of Isatuximab Plus Carfilzomib and Dexamethasone in Relapsed Multiple Myeloma: Ikema Interim Analysis

Depth of Response and Response Kinetics of Isatuximab Plus Carfilzomib and Dexamethasone in Relapsed Multiple Myeloma: Ikema Interim Analysis

Development of a Hydrashift 2/4 Isatuximab Assay to Mitigate Interference with Monoclonal Protein Detection on Immunofixation Electrophoresis in Vitro Diagnostic Tests in Multiple Myeloma

Introduction Evaluation of multiple myeloma (MM) response through quantification of M-protein, by serum protein electrophoresis (SPEP) and immuno-fixation electrophoresis (IFE) is challenging for clinical laboratories because therapeutic monoclonal antibodies (mAbs) can confound IFE when they converge with serum M-protein. This can be misleading when interpreting patients' response to therapy. Isatuximab (Isa), an IgG-kappa anti-CD38 mAb is approved based on the pivotal ICARIA-MM study in combination with pomalidomide (P) and dexamethasone (d), in the United States, the European Union, Canada, Australia, Switzerland and Japan for the treatment of adult patients with relapsed/refractory MM who have received at least two prior therapies including lenalidomide and a proteasome inhibitor. Recently, the Phase 3 IKEMA study evaluating Isa plus carfilzomib (K) and d met its primary endpoint at the first planned interim analysis, demonstrating significantly prolonged progression free survival (PFS) compared with Kd alone in patients with relapsed MM. Methods To overcome the interference mediated by Isa on the IFE test, we have developed an Isa-specific assay "HYDRASHIFT 2/4 Isa" using a highly specific rabbit, anti-Isa mAb. The HYDRASHIFT 2/4 Isa test is used in conjunction with the regular Hydragel IF procedure and the semi-automated Hydrasys 2 electrophoresis apparatus. The HYDRASHIFT 2/4 Isa test displaces Isa (IgG kappa) interference during the electrophoresis process by forming Isa/anti-Isa complex which is moved out of the gamma zone toward the alpha globulin fractions. Results: Sensitivity of the HYDRASHIFT 2/4 Isa assay was demonstrated on serum samples, including normal serum samples. Isa control and serum samples with different monoclonal components spiked with Isa (final concentrations in the range of 0.1 and 3.0 g/L) were analyzed with the HYDRASHIFT 2/4 Isa procedure used in conjunction with Hydragel 4 IF Acid Violet. The detection limit of Isa and/or the Isa / anti-Isa antibody complex visualized was 0.2 g/L. Importantly, efficient removal of Isa from the gamma globulin zone, with no trace signal evident, was demonstrated for all Isa concentrations tested, even for 3 g/L. Reproducibility of the HYDRASHIFT 2/4 Isa assay was also demonstrated between gels, between product lots, between instruments and on different test days. Ten different serum samples, including 1 normal serum sample and 9 serum samples with monoclonal components spiked with Isa at 1 g/L, were run using the HYDRASHIFT 2/4 Isa procedure in conjunction with Hydragel 4 IF Acid Violet. All samples gave 100% concordant results between gels on the different instruments and with different HYDRASHIFT 2/4 Isa lots. To evaluate specificity, 50 serum samples from MM patients were spiked with 1 g/L Isa and the anti-Isa mAb shifted Isa specifically with no impact on the patients' M-spike, demonstrating 100% specificity. Finally, the HYDRASHIFT 2/4 Isa test was evaluated on 15 samples from treated patients enrolled in Isa clinical trials at different therapy cycles. The evaluated samples demonstrated efficient removal of Isa from G and Kappa tracks on the gamma globulins zone and visualization of the Isa/anti-Isa complex on alpha zone and/or Isa on ELP track. For the pre-treatment samples, there was as expected no Isa detection, and no impact on M-protein was observed, further confirming the specificity of the assay toward Isa. Conclusions Therapeutic mAb inclusion in MM treatment regimens offer patients significant improvements in clinical outcomes. With rapid evolution of therapeutic options in MM, there is a clear need for a standardized and reliable method to ensure authentic IFE-based clinical assessment. Development of the Isa-specific HYDRASHIFT 2/4 Isa assay offers the advantage of high clinical utility due to the simplicity of the method as an add-on to the conventional IFE In vitro diagnostic test. Consequently, this assay will facilitate the correct assessment of clinical outcomes for patients receiving Isa as part of their MM treatment. Submission for global regulatory clearance for Isa-specific HYDRASHIFT 2/4 assay is planned in 2020. Disclosures Finn: Sanofi: Current Employment. Macé:Sanofi: Current Employment. Chu:Sanofi: Current Employment. van de Velde:Sanofi: Current Employment, Current equity holder in publicly-traded company. Melki:Sebia: Current Employment.

Comparison of MGUS Prevalence By Race and Family History Risk Groups Using a High Sensitivity Screening Method (MASS-FIX)

Introduction Monoclonal gammopathy of undetermined significant (MGUS) is a premalignant plasma cell disorder that is common in individuals over age 50. MGUS prevalence estimates to date have generally been based on results of serum electrophoresis and immunofixation (for heavy chain [HC] MGUS) and additionally, free light chain (for light chain [LC] MGUS). Mass-spectrometry assays, however, can detect lower levels of monoclonal (M) proteins, identify the isotype and provide accurate quantification of the M-protein. Given the evidence that MGUS is likely present at least 10 years prior to its detection, mass spectrometry may provide more accurate estimates of underlying MGUS. We examined the prevalence of HC-MGUS using matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry among three risk groups: European Americans (EA), African Americans (AA) and first-degree relatives (FDR) of patients with multiple myeloma (MM), MGUS, chronic lymphocytic leukemia (CLL) or non-Hodgkin's lymphoma (NHL). Methods We sampled all AA and a random sample of EA participants ages 50 and older enrolled in the Mayo Clinic Biobank. We also selected unaffected first-degree relatives (limiting to ages 50 and older) from our ongoing family study of hematological malignancies. We screened serum samples by the MALDI-TOF mass spectrometry assay, which is clinically used at Mayo Clinic (known as MASS-FIX) for detection and isotypes of M-proteins. The assay uses isotype-specific nanobody enrichment coupled to MALDI-TOF mass spectrometry. For each of the risk groups, HC- MGUS prevalence was estimated by age (50-59, 60-69, 70+). Age- and sex-adjusted prevalence rates were calculated by direct standardization to the 2010 US population. Ninety-five percent confidence intervals (95% CI) for the prevalence rates and comparisons across the three groups were based on the Poisson distribution. Because free LC information was unavailable, LC-MGUS was not estimated. Results A total 327 AA, 854 EA and 792 FDR were screened for M-proteins using the MASS-FIX assay. All three groups had similar sex (42-44% male) and age distributions (mean[SD] age was 64.5[9.5] yrs., 64.4[8.8] yrs. and 64.9[10.5] yrs. for AA, EA and FDR, respectively). As previously noted using conventional detection methods, the overall prevalence of HC-MGUS was higher in the AA population (16.5% [95%CI: 12.2%, 20.8%]) and FDR (21.5% [95%CI: 18.3%, 24.7%]) than in EA (11.2% [95%CI: 8.8%, 13.5%]), both p-values &amp;lt;0.0001. This pattern was generally seen across age groups (Table 1), with increasing prevalence with age. FDR of MM or MGUS cases had a higher prevalence (22.2% [95%CI: 18.4%, 26.0%]) than FDR of CLL or NHL cases (18.8% [95%CI: 13.3%, 24.4%]), although the difference was not statistically significant (p-value=0.82). Overall prevalence estimates of HC-MGUS using MASS-FIX were at least three-fold higher than estimates using conventional methods alone (i.e. age- and sex-adjusted prevalence in Olmsted County, MN, was 3.1% [95% CI: 2.9%-3.4%]). Conclusion We provided some of the first data on prevalence of HC-MGUS across three risk groups, using a sensitive method for detecting monoclonal proteins. The MASS-FIX assay resulted in substantially higher absolute rates of HC-MGUS (at least 3-fold higher) relative to conventional methods. Further, the prevalence of HC-MGUS among the AA and FDR was significantly higher than the EA population. Thus, the more sensitive assay identified greater absolute numbers of individuals with MGUS, but resulted in similar relationships as seen in prior studies across these risk groups. Our results have implications for future studies of the etiology of MGUS and its progression. Disclosures Dispenzieri: Janssen: Research Funding; Pfizer: Research Funding; Alnylam: Research Funding; Intellia: Research Funding; Celgene: Research Funding; Takeda: Research Funding. Kumar:Amgen: Consultancy, Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments, Research Funding; Janssen Oncology: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Takeda: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; AbbVie: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Karyopharm: Consultancy; Genecentrix: Consultancy; Cellectar: Other; Carsgen: Other, Research Funding; Merck: Consultancy, Research Funding; Dr. Reddy's Laboratories: Honoraria; Adaptive Biotechnologies: Consultancy; Celgene/BMS: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Genentech/Roche: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Oncopeptides: Consultancy, Other: Independent Review Committee; IRC member; Kite Pharma: Consultancy, Research Funding; BMS: Consultancy, Research Funding; Tenebio: Other, Research Funding; Sanofi: Research Funding; MedImmune: Research Funding; Novartis: Research Funding. Murray:The Binding Site: Patents &amp; Royalties: Patent Use of Mass Spec to identify monoclonal proteins licensed to The Binding Site.

Successful Treatment of Concurrently Diagnosed Multiple Myeloma and Myelodysplastic Syndrome with Isolated Del(5q) with Lenalidomide, Bortezomib, and Dexamethasone

Lenalidomide is known to be an effective therapy for multiple myeloma (MM) and for myelodysplastic syndrome with isolated del(5q). However, there have been very few reports of treatment of both conditions using lenalidomide when they are diagnosed concurrently. A review of the literature revealed two reports of MM and del(5q) MDS treated with lenalidomide. We report the case of a patient simultaneously diagnosed with multiple myeloma and myelodysplastic syndrome with isolated del(5q) who was treated successfully with lenalidomide. The patient is a 74 year old female who was referred to hematology for worsening chronic macrocytic anemia with a hemoglobin of 9.4 g/dL. A serum protein electrophoresis (SPEP) was obtained during her workup and demonstrated an IgG kappa monoclonal spike of 4.7 g/dL. Free light chain analysis demonstrated a kappa/lambda ratio of 36.7. The patient was mildly hypercalcemic at 10.6 g/dL but had no renal insufficiency. Platelet and white blood cell counts were normal. There were no osteolytic lesions on skeletal survey and a whole body PET scan identified no bony disease or plasmacytomas. A β-2 microglobulin level was 3.7 mg/L and albumin was 3.3 g/dL. Bone marrow biopsy revealed 60% plasma cells in a 70% cellular marrow. Granulocytic and megakaryocytic dysplasia was identified. Fluorescence in situ hybridization returned showing a 4:14 translocation in 72% of analyzed nuclei and monosomy 13 in 61% of nuclei analyzed consistent with an unfavorable risk profile. Chromosome analysis also revealed a 5q deletion in 15 of 20 analyzed cells. Bone marrow blasts were measured at 1%. Therefore, the patient concurrently met diagnostic criteria for stage II IgG kappa multiple myeloma per the International Staging System and low risk myelodysplastic syndrome with isolated del(5q) per the 2016 WHO classification of MDS with a Revised International Prognostic Scoring System Score (IPSS-R) of 2. She was started on lenalidomide 25 mg daily, bortezomib 1.3 mg/m2 on days 1, 4, 8, and 11 and dexamethasone 20 mg on days 1, 8, and 15 of a 21 day cycle. After 3 cycles of therapy, serum immunofixation electrophoresis showed an unquantifiably low IgG kappa monoclonal spike and the patient's kappa/gamma light chain ratio had normalized to 1.1. Hemoglobin and calcium returned to normal. On repeat bone marrow biopsy, there was normocellular marrow with 4% polytypic plasma cells by kappa/lambda immunohistochemistry. No dysplasia was identified and bone marrow blasts were 1.5%. Therefore, the patient achieved a very good partial response (VGPR) to therapy for multiple myeloma according to International Myeloma Working Group criteria within 3 months. She met National Comprehensive Cancer Network criteria for response of her MDS to lenalidomide by normalization of hemoglobin. The patient's case demonstrates successful treatment of concurrently diagnosed multiple myeloma and MDS with isolated del(5q) using lenalidomide. Among the two other similar cases we discovered in the literature, one patient was treated with low-dose lenalidomide and dexamethasone [Nolte, et al. Eur J Haematol. 2017 Mar;98(3):302-310.], and the other patient was treated with high-dose lenalidomide and dexamethasone, achieving a partial response [Ortega, et al. Leuk Res. 2013 Oct;37(10):1248-50.]. Neither patient received a proteasome inhibitor. In our case, the patient was treated with higher intensity induction therapy for multiple myeloma and achieved a VGPR. She did not have worsening cytopenias during therapy, and in fact experienced normalization of her blood counts. Therefore, it is reasonable to treat patients simultaneously diagnosed with MM and MDS with isolated del(5q) with standard three-drug induction therapy for multiple myeloma. While our approach makes sense in the abstract, hematology/oncologists should be aware that it works in practice. Disclosures No relevant conflicts of interest to declare.

Sequential Comparison of Conventional Serum Immunofixation (IFE) to Mass Spectrometry-Based Assessment (MASS FIX) in Patients with Multiple Myeloma (MM)

Sequential Comparison of Conventional Serum Immunofixation (IFE) to Mass Spectrometry-Based Assessment (MASS FIX) in Patients with Multiple Myeloma (MM)

A Phase II Study of Isatuximab (SAR650984) (NSC-795145) for Patients with Previously Treated AL Amyloidosis (SWOG S1702; NCT#03499808)

A Phase II Study of Isatuximab (SAR650984) (NSC-795145) for Patients with Previously Treated AL Amyloidosis (SWOG S1702; NCT#03499808)

Detection of M-Protein in Acetonitrile Precipitates of Serum Using MALDI-TOF Mass Spectrometry: A Novel Methodology

Background: Multiple myeloma (MM) and plasmacytoma(s) belong to a group of clonal plasma cell dyscrasias. In 97-98% of all cases, they are characterised by the detection of a monoclonal protein (M-protein) in the blood, and sometimes in the urine. MALDI-TOF-mass spectrometry (MS) has demonstrated excellent analytical sensitivity for the screening and detection of M-protein. We present the results of a novel methodology for M-protein analysis by MALDI-TOF MS. Patients and Methods: Blood samples from patients and controls were collected after obtaining Institutional Ethics Committee approval. The work was carried out in accordance with the Declaration of Helsinki after obtaining written informed consent. Patients with confirmed multiple myeloma or plasmacytoma and M-protein detected by serum protein electrophoresis (SPEP), serum immunofixation electrophoresis (IFE), and serum free light chains (FLC) were included for MALDI-TOF MS analysis. IFE and FLC analysis were sent to independent laboratories for external validation of the MALDI-TOF MS results. Reagent-based extraction The serum fraction was separated from whole blood by centrifugation at 5000 rpm for 15 minutes and stored at -80oC until further analysis. Twenty-five μL of the serum sample was mixed with 50% acetonitrile (ACN) to form a precipitate. After precipitation and incubation, the mixture was centrifuged. The protein precipitate was washed with 20% ACN. After centrifugation, the supernatant was discarded, and the precipitate was reconstituted in a buffer comprising 10% formic acid (FA) and 50 mmol/L tris(2-carboxyethyl)phosphine hydrochloride (TCEP). The MALDI-TOF MS results were validated using immunoenrichment by anti-kappa (κ) and anti-lambda (λ) biotin-labelled antibodies immobilised on streptavidin magnetic beads. MALDI-TOF MS measurements were obtained for intact proteins using alpha-cyano-4-hydroxycinnamic acid as a matrix. The images obtained were overlaid on apparently healthy serum samples to confirm the presence of M-protein. The samples were then analysed using UltraflexTM LT, Bruker MALDI/TOF-TOF mass spectrometer. The mass spectra for each sample was exported to FlexAnalysis 3.3 (Bruker Daltonics) and background subtracted. A sample was considered positive for M-protein if there was a sharp or broad peak within the κ or λ mass/charge (m/z) range- κ m/z- [M+2H]2+: 11550-12300 Da; [M+H]+: 23100-24600 Da), and λ m/z- [M+2H]2+: 11100-11500 Da; [M+H]+: 22200-23100 Da. All the images were acquired at a m/z range of 10000-29000 Da. Mass measurement was analysed with a summation of 500-5000 shots depending on the intensity of the M-peak. Results: Twenty-seven patient samples: 24- multiple myeloma, and 3- plasmacytoma with an M-protein identified by other biochemical tests, were chosen for ACN precipitation and analysed by MALDI-TOF MS. The median age was 62 years (range:44-72); males-12 (44%). A mass spectrometrist, S.J was blinded to the IFE and FLC results- blinded analyst. N.M was the unblinded analyst. Neat sample (without dilution) was spotted on the MALDI plate for all the control and patient samples. The Gaussian distribution of κ and λ light chains were obtained by analysing 20 serum samples of apparently healthy blood donors. All the 27 samples (100%) with M-protein confirmed by the other biochemical techniques, demonstrated a peak suggestive of M-protein with mass/charge (m/z) falling within the κ or λ range on MALDI-TOF MS: 24 patients with κ peak, and 3 with λ peak. (Fig. 1a and 1b) Immunoenrichment was performed on two samples- 1 with κ peak, and the other with λ peak, analysed by MALDI-TOF-MS by ACN precipitation. The mass spectra by immunoenrichment and ACN precipitation were found to be identical with the light chain m/z falling within their respective range. (Fig. 2 and 3) Three samples were labelled as confounders due to low peak intensity. However, their peaks matched their corresponding IFE and FLC reports. Concordance between MALDI-TOF MS and IFE was observed in 21/23 patients (91%); concordance between MALDI-TOF MS and FLC was observed in 23/24 patients (96%). Conclusions: We report the results of a low-cost, reagent-based extraction process using ACN precipitation to enrich for κ and λ light chains, which can be used for screening and for qualitative analysis of M-protein. Further studies are required to identify the immunoglobulin isotype, and to quantify the M-protein by this methodology. Disclosures No relevant conflicts of interest to declare.

S2935 Gastric Mass: A Case of Primary Amyloidosis

INTRODUCTION: We present a rare case of primary amyloidosis presenting as a bleeding gastric mass. Involvement of the gastrointestinal tract is very common in systemic amyloidosis (30-60%), but very rare in primary amyloidosis (8%). CASE DESCRIPTION/METHODS: An 81-year-old man presented to the hospital with anemia with a hemoglobin of 5.3 g/dL. Symptoms on presentation included severe generalized weakness and weight loss. Lab results showed MCV 94.3, Iron 26 ug/dl, Ferritin 15 ng/dl. Upper endoscopy revealed a large ill-defined mass in the gastric body with diffuse ulcerations, friable mucosa, and intramural hematoma (Figure 1). The mass was biopsied, and histology revealed Congo red positive amorphous proteinaceous material consistent with amyloid with apple-green birefringence under polarized light. (Figures 2A and 2B). Serum protein electrophoresis revealed a gamma monoclonal gammopathy. Serum immunofixation showed an IgG kappa and a free light chain lambda. A serum-free light chain assay was not obtained. A bone marrow biopsy revealed plasmacytosis, adjunct flow cytometry showed CD 38 + Plasma cell population with cytoplasmic kappa light chain excess/restriction. These findings where indictive of primary light chain amyloidosis (AL) and excluded the diagnosis of multiple myeloma or systemic amyloidosis (AA). DISCUSSION: Primary amyloidosis is a rare entity. The reported incidence in a population-based study was approximately 1 case per 100,000 population per year. Fatigue and weight loss are the most common clinical manifestations. Hemorrhagic manifestations, congestive heart failure, nephrotic syndrome, malabsorption, and constipation are all relatively common. The diagnosis is made by establishing the presence of amyloid in tissue. Amyloid is amorphous, waxy-appearing, and pink in H&E slides. The Congo red stain is the most used technique for confirming amyloid in a tissue biopsy. characteristic apple-green birefringence under polarized light is seen. Involvement of the gastrointestinal tract is very common in systemic amyloidosis (30–60%), but very rare in primary amyloidosis. The exact prevalence of primary amyloidosis involvement of the stomach is unknown, but the involvement of the upper gastrointestinal tract appears to be present in 8% of all cases. The mainstay treatment is chemotherapy. primary amyloidosis has a poor prognosis when compared to systemic amyloidosis with a predicted median survival of <2 years despite treatment.Figure 1.: Large ill-defined mass in the gastric body with diffuse ulcerations and friable mucosa.Figure 2A.: Congo red positive amorphous proteinaceous material.Figure 2B.: Apple green birefringence under polarized light.

A Rare Case of Infiltrative Cardiomyopathy: Diagnostic Dilemma

Presentation A 73-year-old white female with history of bilateral carpal tunnel syndrome, lumbar spinal stenosis, and family history of cardiomyopathy presented with worsening dyspnea on exertion. Exam showed right-sided crackles. There was no jugular venous distention, edema, macroglossia, or peri-orbital ecchymosis. Evaluation ECG demonstrated low voltage in all leads and no significant ST segment changes (Figure 1A). Labs showed undetectable troponin-I and normal NT-proBNP (119pg/mL). TTE revealed LVEF 55-65%, grade II diastolic dysfunction, thick and bright ventricular walls and global longitudinal strain of -17.9% with relative apical sparing (Figure 1B, Figure 1C). TTE findings raised concern for an infiltrative cardiomyopathy, specifically amyloidosis. Additional labs found polyclonal gammopathy on serum immunofixation with increased IgA (590mg/dL), kappa (20.4mg/L) and lambda (14.0mg/L). However, free kappa-to-lambda ratio (1.46) was normal. There was no monoclonal spike on urine immunofixation. Anti-neutrophil antibody screen was negative, and cobalt was undetectable. Ferritin (17ng/mL), C-reactive protein (0.8mg/L), and erythrocyte sedimentation rate (27mm/hr) were normal. Cardiac MRI found mild concentric left ventricular wall thickening up to 11 mm and late gadolinium enhancement throughout the myocardium (Figure 1D). Endomyocardial biopsy showed patchy fibrosis but no evidence of amyloidosis on Congo red staining. No granulomatous disease or inflammatory infiltrate was seen. Cutaneous nerve biopsy was also negative for amyloidosis. Technetium-99m pyrophosphate scan was negative for transthyretin amyloidosis with normal heart-to-lung ratio (1.3). Genetic testing for infiltrative cardiomyopathy genotypes revealed phenotypically silent heterozygosity for HFE hereditary hemochromatosis. Hereditary amyloidosis testing was negative. Follow-up Twelve-day ambulatory cardiac monitoring showed 11% PVC burden with multiple morphologies and three episodes of non-sustained VT. Amiodarone 200mg daily was initiated as opposed to therapeutic ablation due to multifocal nature of PVCs. The patient continued to have dyspnea on exertion but remained functionally independent. PET imaging was attempted, however the patient did not tolerate the dietary preparation. Conclusions A total evaluation is essential for infiltrative cardiomyopathy. History, exam, and preliminary testing in this case suggested cardiac amyloidosis; however, comprehensive evaluation could not support this diagnosis or an alternate mechanism. Despite diagnostic innovations including advanced cardiac imaging and genetic testing, the cause of infiltrative cardiomyopathy can remain obscure.

Extraosseous Plasmacytoma of Thyroid Arising in Hashimoto’s Thyroiditis

Plasma cell neoplasms of the thyroid gland are uncommon. They may occur either as a primary extraosseous (extramedullary) plasmacytoma or as secondary involvement by multiple myeloma (MM). Here, we report the case of a 62-year-old female, presenting with goiter and Hashimoto’s thyroiditis, in whom the histologic diagnosis of extraosseous plasmacytoma was unexpected. Histology of the total thyroidectomy specimen showed a diffuse infiltration of well-differentiated plasma cells against a background of Hashimoto’s thyroiditis. By immunohistochemistry, the majority of the plasma cells are positive for IgG heavy chain and kappa light chain (kappa:lambda ratio was about 6-7:1). PCR analysis of the immunoglobulin heavy and kappa chain (IGH, IGK) gene rearrangements showed clonal IGH and IGK gene rearrangements. MM was ruled out by lack of MM-related end organ damage and negative serum protein electrophoresis, immunofixation, and bone marrow biopsy. Although rare, plasmacytoma should be considered in patients presenting with enlarging thyroid gland and autoimmune thyroiditis. Histologic diagnosis and differential diagnoses are comprehensively discussed.

Prevalence and characteristics of myeloproliferative neoplasms with concomitant monoclonal gammopathy

Of BCR-ABL negative myeloproliferative neoplasm (MPN) patients, 3–14 % display a concomitant monoclonal gammopathy (MGUS). Nonetheless, literature on co-occurring MPN and MGUS is scarce, the molecular underpinnings are unknown and it is unclear whether patients require a specific management. Here, we compared the clinical and genetic features of MPN patients with and without concomitant MGUS. Of 114 MPN patients prospectively studied by serum immunofixation (median age, 67 years; 36.0 % essential thrombocythemia [ET], 24.6 % polycythemia vera [PV], 11.4 % secondary myelofibrosis [sMF], 28.1 % primary myelofibrois [PMF]; 73.7 % JAK2 V617F positive), 10 (9 %) harbored an M-protein. No relevant clinical differences existed between MPN patients with or without M-protein. Seven additional MPN/MGUS patients were retrospectively identified in our MPN registry, yielding a total of 17 patients (7 ET, 3 PV, 3 sMF, 4 PMF). One patient developed multiple myeloma (MM) and one smoldering MM. Seven of 12 patients analyzed carried mutations (e.g. in ASXL1 or TET2) in addition to those in JAK2 or CALR, and 4 of 10 patients showed aberrant cytogenetics. M-protein was mainly IgG (12/17), followed by IgM (4/17). In the two patients that underwent allogeneic stem cell transplantation mutant JAK2 and M-protein were no longer detectable post-transplant. In conclusion, MGUS prevalence in our cohort was in the range of previous reports and at most slightly higher than expected in the general population. MGUS presence did not correlate with a specific MPN entity, clinical features or genetic alterations. Our observations suggest that there is no strong clinical or biological relationship between the occurrence of MGUS and MPN.

MM-230: Solitary Extramedullary Plasmocytoma Mimicking a Primary Breast Cancer

Extramedullary plasmocytoma is a plasma cell neoplasm that arises outside the bone marrow in the absence of any other sign of multiple myeloma. Breast plasmocytoma has been reported as part of disseminated disease. However, primary solitary breast plasmocytoma is rarely described. Here, we present a case of solitary extramedullary breast plasmocytoma mimicking a primary breast tumor. A 50-year-old female patient presented to our clinic for a left breast lump of one month duration without any associated systemic symptoms. Mammography and breast ultrasound showed a suspicious, well-defined, 2-cm mass in the left upper quadrant without ipsilateral lymphadenopathies. Tru-cut biopsy from the breast lesion revealed unexpectedly atypical monoclonal plasma cells (kappa monoclonality). Serum protein electrophoresis and immunofixation of serum protein, as well as urine protein electrophoresis and Bence Jones proteins, were negative for any M-protein/monoclonal gammopathy. Bone marrow aspirate and biopsy disclosed less than 3% clonal plasma cells. 18F-FGD PET-CT did not show any lytic lesions nor other pathologic findings. These results supported the diagnosis of solitary extramedullary plasmocytoma of the breast. Subsequently, our patient was referred for wide local excision of the solitary lesion. She received a consolidative radiation therapy post-operatively. Fifteen months later, the patient is on regular follow-up without detection of any monoclonal gammopathy. Usually, extramedullary plasmocytoma occurs in the head and neck. Few cases are reported in the breast. Clinicians should be aware of this entity, mimicking primary breast cancer. It does not have specific clinical or radiological features. The diagnosis requires: extramedullary tumor with evidence of clonal plasma cells, normal skeletal survey, no M-protein in serum and/or urine, and no bone marrow involvement. Soft tissue extramedullary plasmocytomas have better prognosis than plasmocytomas occurring in bone. The treatment of choice is radiation therapy with curative intent and low risk of recurrence after tumoricidal radiation.

Indicators of profound hematologic response in AL amyloidosis: complete response remains the goal of therapy

In AL amyloidosis complete response (aCR) is defined as negative serum and urine immunofixation with normalized free light chain ratio (FLCR). However, achievement of low levels of involved FLC (iFLC) or difference between iFLC and uninvolved FLC (dFLC) are also relevant endpoints for treatment. We divided 434 consecutive patients with AL amyloidosis into five groups according to response 6 months after treatment initiation: aCR, iFLC <20 mg/L, normalized-iFLC, dFLC <10 mg/L, and normalized FLC ratio. Overall survival (OS) was similar (median not reached) in patients in aCR and in those who reached iFLC <20 mg/L, while it was inferior in all other groups (medians ranging from 79 to 91 months). Time to next therapy or death (TNTD) was longer in subjects attaining aCR (median 69 months) than in subjects reaching any FLC endpoint (medians ranging from 18 to 39 months). The ability of discriminating patients who survived more than 2 years among all responders was greater for current definition of aCR compared to combination of negative serum and urine immunofixation with any low-FLC endpoint. Complete response predicts best outcomes in AL amyloidosis and should be the goal of therapy if tolerability allows.