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Multi-frequency Electrocochleography Measurements can be Used to Monitor and Optimize Electrode Placement During Cochlear Implant Surgery
Saoji, Aniket A. , Patel, Neil S. , Carlson, Matthew L. , Neff, Brian A., Koka, Kanthaiah , Tarigoppula, Venkata S Aditya , Driscoll, Colin L. W.

Otology & Neurotology | October 23, 2019 | Volume: 40 | Issue: 10 | Pages: 1287-1291

10.1097/mao.0000000000002406 | PMID 31644474 Get It

Objective: To report the use of multi-frequency intra-cochlear electrocochleography (ECOG) in monitoring and optimizing electrode placement during cochlear implant surgery. An acoustic pure tone complex comprising of 250, 500, 1000, and 2000 Hz was used to elicit ECOG, or more specifically cochlear microphonics (CMs), responses from various locations in the cochlea. The most apical cochlear implant electrode was used as the recording electrode. Study Design: Clinical capsule report. Setting: Tertiary academic referral center. Results: ECOG measurements were performed during cochlear implant surgery in an adult patient with significant residual acoustic hearing. The 500, 1000, and 2000 Hz CM tracings from the most apical electrode showed an amplitude peak at three different instances during the early phase of cochlear implant electrode insertion. These results are consistent with the tonotopic organization of the cochlea. During final electrode placement a slight advancement of the electrode array resulted in a correlated decrease in 250, 500, and/or 1000 Hz CM amplitude. The electrode array was retracted and repositioned which resulted in a recovery of CM amplitude. Intraoperative CM thresholds revealed a correlation of r = 0.87 with preoperative audiometric thresholds. Conclusion: We present a report on simultaneous multi-frequency ECOG monitoring during cochlear implant surgery. Multi-frequency ECOG can be used to differentiate between electrode trauma and the advancement of the apical electrode beyond the CM source in the cochlea.
Bay 94-9027 Can be Accurately Measured across Regions with Appropriate One-Stage Assay Reagent Use
Pruthi, Rajiv K. , Castellone, Donna D. , Church, Nikki , Leong, Lilley , Kitchen, Steve

Blood | October 14, 2019 | Volume: 132 | Issue: Supplement 1 | Pages: 2481-2481

10.1182/blood-2018-99-113493 Get It

Abstract Introduction: Differences in coagulation assay reagents may lead to variable results for some extended-half-life (EHL) recombinant factor VIII (rFVIII) products, with the potential to adversely affect patient care. Laboratories assessing EHL-rFVIII activity can choose from many available one-stage assay and chromogenic assay reagents. A field study was conducted to evaluate the ability of clinical laboratories to accurately measure FVIII activity in plasma samples spiked with BAY 94-9027, an EHL rFVIII, when using diverse assay reagents and when guided in the choice of reagent. In a regional subanalysis, BAY 94-9027 field study results from clinical laboratories in the United States and Canada were compared with those from Europe and Israel. Methods: In this 2-part study, a broad range of laboratories in the United States, Canada, Europe (Austria, Germany, Italy, Romania, Spain, Switzerland, United Kingdom), and Israel were provided samples containing defined concentrations of BAY 94-9027 or an unmodified rFVIII (antihemophilic factor [recombinant] plasma/albumin-free method [rAHF-PFM]) as a control. In part 1, each laboratory measured FVIII activity using their routine methods (one-stage assay, chromogenic assay, or both); laboratories that had ≥2 routine one-stage assays were asked to perform sample testing with one of the less commonly used assays in the laboratory to ensure that part 1 captured both the prevalence and heterogeneity of one-stage assays used in the geographic regions studied. In part 2, laboratories used one-stage assays with SynthASil and Pathromtin SL reagents provided by Bayer; SynthASil and Pathromtin SL have previously been shown to accurately measure BAY 94-9027 and full-length rFVIII products. The field study data were analyzed to identify the most commonly used reagents in the 2 regions (United States/Canada and Europe/Israel) and to assess if regional differences resulted in differences in accuracy of FVIII activity measurement. Results: 52 laboratories (US/Canada, n=25; Europe/Israel, n=27) participated in the field study. The one-stage reagent SynthASil was commonly used in all countries (n=15) in part 1, but differences were seen in the frequency of use of other reagents. PTT-A (n=6) and Actin FSL (n=5) were frequently used in the US/Canada and Actin FS (n=6) and Pathromtin SL (n=6) in Europe/Israel. Regional differences in the choice of assay, with US/Canada more likely to use assays that did not accurately measure BAY 94-9027, affected the ability of laboratories to accurately measure FVIII activity in the spiked samples (Figure). In part 1 of the study, regional differences in median recovery of BAY 94-9027 were seen among laboratories when using their own in-house one-stage assays. These differences were not seen in part 2 of the study when laboratories used provided reagents (SynthASil and Pathromtin SL), despite using the same instrumentation as used in part 1. Regional differences in part 1 might have been exacerbated by use of less common, and potentially inappropriate, one-stage assay reagents, affecting the accuracy of BAY 94-9027 measurement. Chromogenic assay use was more common in Europe/Israel (n=11) than US/Canada (n=5). No regional differences in chromogenic assay results were observed. Conclusions: Most clinical laboratories were able to accurately measure BAY 94-9027 activity using their in-house assays. However, regional differences in the accurate measurement of BAY 94-9027 activity were influenced by regional choice of one-stage reagents used in part 1 of the study; the activity and accuracy differences were eliminated when all laboratories used the same provided one-stage reagents with their in-house instruments (part 2 of study). Therefore, standardization of laboratory procedures and use of newer, more accurate one-stage assay reagents should improve measurement of FVIII activity with EHL products. Figure. Figure. Disclosures Castellone: Bayer: Membership on an entity's Board of Directors or advisory committees; Wilmer-Hale: Consultancy. Church:Bayer: Employment. Leong:Bayer: Employment. Kitchen:Bayer: Consultancy, Other: travel reimbursement, Speakers Bureau.
Dietary Products Induce Apoptosis in CLL B Cells and Reveal Potential as a Therapeutic Combination That Can Overcome Stromal Cell Mediated Protection.
Ghosh, Asish K. , Secreto, Charla, Shanafelt, Tait D. , Kay, Neil E.

Blood | October 13, 2019 | Volume: 110 | Issue: 11 | Pages: 3130-3130

10.1182/blood.v110.11.3130.3130 Get It

Abstract Background: B-cell chronic lymphocytic leukemia (CLL) is characterized by defects in the level of apoptosis rather than accelerated leukemic cell proliferation. We have been interested in identification of naturally occurring substances that induce apoptosis in CLL B cells with potential for therapeutic application with a favorable toxicity profile. Two such agents, epigallocatechin-3-gallate (EGCG) in green tea and curcumin from the spice turmeric have recently been studied by our laboratory. We have shown previously that in vitro treatment of CLL B cells with EGCG induces apoptosis [Blood, 2004, 104:788] and is now being tested in a Phase I/II clinical trial. In this study, we explored the possibility of using curcumin in the induction of CLL B cell apoptosis either alone or in combination with EGCG. We also tested their ability to induce CLL B cell apoptosis in the presence of human stromal cells. Results: In vitro treatment of CLL B cells with curcumin induces apoptosis in a dose (5–20 μM) and time dependent manner. Further analysis suggested that curcumin treatment inhibited the effects of the constitutively active proteins STAT3, AKT and NF-κB and suppressed expression of XIAP in CLL B cells. Interestingly, we observed that curcumin/EGCG combination was more effective in the induction of apoptosis in CLL B cells as compared to the corresponding individual dose of the drug alone. We next evaluated the effects of curcumin when CLL B cells were co-cultured with the human stromal cell line HS-5. Curcumin-induced apoptosis was significantly inhibited when CLL B cells were co-cultured in physical contact with HS-5 cells. We also found protection against curcumin-induced cell death, albeit less, when CLL B cells were co-cultured with HS-5 separated by transwells. However, higher doses of curcumin can overcome HS-5 mediated apoptosis-protection of CLL B cells in transwells but, did not overcome the protective effect of physical contact with HS-5. Further analysis of CLL B cells co-cultured with HS-5 in transwells demonstrated elevated levels of STAT3 with increased phosphorylation at serine-727 and increased expression of Mcl-1 and XIAP. At this stage, we employed combined therapeutic approach to evaluate whether combining curcumin with EGCG could overcome stromal cell-mediated protection. Interestingly, combined treatment of CLL B cells could significantly overcome stromal cell-mediated protection against apoptotic cell death, although the effect was more pronounced when CLL B cells were separated by transwells (see figure below). Conclusion: Together, these results suggest that curcumin induces apoptosis in CLL B cells in vitro and may mediate its effects by suppressing the constitutively active signaling pathways that are known to be important in apoptosis resistance This work also demonstrates that stromal cells and their soluble products can resist drug-induced apoptosis of leukemic CLL B cells. Importantly, the apoptosis-inducing activity of curcumin and EGCG is not impaired completely in the presence of stromal cells, suggesting that the combination of curcumin/EGCG may warrant clinical testing in patients with CLL. Figure. Combined treatment of CLL B cells with curcumin/EGCG reduces stromal cell mediated protection against apoptosis. CLL B cells were cultured alone or co-cultured with HS-5 cells and treated with the indicated doses of curcumin (C) and/or EGCG (E). After 24h, cells were collected for Annexin/PI staining for flow cytometric analysis. Mean percent of annexin/PI positive cells are presented with standard error bars. Figure. Combined treatment of CLL B cells with curcumin/EGCG reduces stromal cell mediated protection against apoptosis. CLL B cells were cultured alone or co-cultured with HS-5 cells and treated with the indicated doses of curcumin (C) and/or EGCG (E). After 24h, cells were collected for Annexin/PI staining for flow cytometric analysis. Mean percent of annexin/PI positive cells are presented with standard error bars.
Functional P2X7 Receptors in Myeloma Cell Lines and Myeloma Patient Bone Marrow Samples Can Be Blocked by Specific P2X7 Receptor Antagonists: Implications for Myeloma Therapy and Chemotherapy Induced Inflammation.
Donovan, Kathleen A., Moon‐Tasson, Laurie L., Hromockyj, Alexander E., Meyer, Debra M., Stone, Andrew D, Lust, Michael J, Lust, John A.

Blood | October 12, 2019 | Volume: 118 | Issue: 21 | Pages: 1845-1845

10.1182/blood.v118.21.1845.1845 Get It

Abstract Abstract 1845 Inflammation is a driving factor in the pathogenesis of many cancers including multiple myeloma (MM). The active role that cytokines play, IL-1β in particular, during the early stages of MM has been extensively characterized. Myeloma is a plasma cell tumor whose early stages are characterized by cytokine dependent growth, predominantly driven by IL-6. We have demonstrated that IL-1β is a key inducer of IL-6 expressed by bone marrow stromal cells in a paracrine fashion during the progression of multiple myeloma from smoldering myeloma (SMM) to active disease (Mayo Clinic Proc 84:114 (Feb. 2009)). Elevated ATP levels have been documented in vivo in tumor micro-environments and is a potential contributing factor to IL-1β induced inflammation. The P2X7 receptor (P2X7R) is an ATP-gated ion channel expressed by cells of the hematopoetic lineage that has been shown to play a critical role in IL-1b processing and secretion. We investigated the role this receptor may have in the release of IL-1β in the bone marrow microenvironment using bone marrow samples from both chemotherapy treated and untreated patients. Myeloma cell lines were evaluated by RT-PCR for the expression of P2X7R mRNA. Expression was detected and confirmed by sequencing in ANBL-6, MM1.S, U266, RPMI-8226 and KAS-6/1 and was comparable to U937, a previously characterized P2X7R positive cell line. A newly derived plasmacytoma cell line, PCYT3, showed very low levels of message expression. The ability of ATP, the P2X7R agonist, to trigger the processing and release of IL-1β by activation of the P2X7 channel was studied using KAS-Pro, a myeloma cell line stably transfected with a pro- IL-1β gene. IL-1β, measured by ELISA, was released in a dose dependent fashion in response to increasing amounts of ATP ranging from.6mM to 5mM. Four P2X7R specific antagonists were tested for their effect on ATP stimulated IL- 1β release from KAS-Pro; all 4 compounds demonstrated inhibition in a dose dependent manner with varying degrees of potency correlating with P2X7R inhibition. In addition fresh patient samples (8 MGUS/7SMM/9 newly diagnosed MM as well as 12 Treated MM) were evaluated for receptor expression and function. All stages of disease expressed the receptor by RT-PCR. Analysis of samples from all stages of MM, as measured directly by IL-1β ELISA as well as indirectly by measurement of IL-1β induced IL-6 production from normal bone marrow stromal cells, showed functional receptor activation in response to ATP stimulation. IL-6 production detected from MGUS patient samples had a mean result of 2,253 pg/ml, the mean for SMM was 5,495 pg/ml, MM were 6,875 pg/ml while treated MM samples showed a mean result of 15,219 pg/m. Greater than 90% inhibition of IL-1β release by the P2X7R antagonists was seen for all patients who demonstrated a positive ATP induced IL-1β release (see figure). We observed a greater than 2 fold increase in IL-1β release between the treated MM samples and the newly diagnosed MM samples, suggesting a chemotherapy induced inflammation process may be ongoing in these patients. These results confirm the activity of functional P2X7 receptors on myeloma cell lines and in fresh patient samples and suggest a role for the use of P2X7 receptor antagonists in the therapy of myeloma, particularly in patients undergoing chemotherapy. Disclosures: Hromockyj: Pfizer Corporation: Employment. Meyer:Pfizer Corporation: Employment.
CLL Cells From Subjects Treated with Rituximab and Alemtuzumab Can Lose Target Antigen and Develop Resistance to Mab-Mediated Complement Dependent Cytotoxicity
Beum, Paul V., Lindorfer, Margaret A. , Taylor, Ronald P. , Zent, Clive S. , Weiner, George J.

Blood | October 12, 2019 | Volume: 116 | Issue: 21 | Pages: 3585-3585

10.1182/blood.v116.21.3585.3585 Get It

Abstract Abstract 3585 Relapsed/refractory CLL is often resistant to antibody-based therapy. Understanding the dynamics of interaction between complement and cell-based antibody-antigen complexes that promote complement dependent cytotoxicity (CDC) of targeted cells could lead to improved therapies. We are conducting a clinical trial of chemoimmunotherapy for relapsed/refractory CLL using pentostatin, alemtuzumab (ALEM), and low-dose rituximab (RTX). Correlative studies were designed to determine if circulating CLL cells developed resistance to CDC. Peripheral blood CLL cells were obtained from 12 patients (median age 66 years, 11 male, 17p13- in 4) including 7 (58%) who responded (4 CR, 3 PR) to treatment. Blood samples were obtained before initiating therapy (day 1), 48 hr after the 1st RTX dose (20 mg/m2 IV MWF), one hour after the 2nd dose of RTX and 1st dose of ALEM (3 mg SC) (day 3), and 72 hr after the 3rd doses of RTX (cumulative dose 60 mg/m2) and ALEM (cumulative dose 43 mg) (day 8). All blood samples were taken prior to the 1st dose of pentostatin. B cells were examined for expression of several markers including complement control proteins (CCP), CD20 and CD52. By treatment day 8, ALC decreased by 70 % or more for 7 patients. The other 5 patients had ALC that were 50 – 100% of pre-treatment levels. In agreement with previous studies from our laboratories, low-dose RTX rapidly decreased CD20 levels on circulating CLL cells; on day 3 after the 2nd RTX dose (and 1st ALEM dose), CD20 was reduced by > 75% in 10 subjects. CD20 levels recovered by day 8 in 6 of these subjects. One hour after completion of mAb infusions on day 3, fragments of complement breakdown product C3dg were demonstrable on circulating CLL cells in 7 subjects, suggesting that infusion of RTX had promoted complement activation on circulating cells. After the RTX and ALEM infusions on day 3, circulating CLL cells with bound C3dg fragments had considerably reduced levels of CD20 but were not cleared from the circulation, suggesting that RTX had bound to the cells, activated complement and promoted shaving (CD20 loss) without inducing bloodstream clearance of these cells. CD52 levels on circulating CLL cells showed modest decreases by day 8 (~ 50% of pre-treatment values) in 4 subjects. To study CDC in vitro, washed blood samples were reconstituted with ABO-matched normal human serum, ALEM was added and complement activation (C3 fragment deposition) and CDC of targeted CLL cells were measured by flow cytometry. Alternatively, mononuclear cells were isolated by ficoll-hypaque centrifugation and subjected to the same analyses, with very similar results. ALEM-mediated in vitro CDC of CLL cells varied from 10 to 90 % for pre-treatment blood samples. Measures of ALEM-mediated CDC and C3b fragment deposition in vitro correlated with the density of CD52 on CLL cells (P<0.001). The initial burden of circulating cells was not predictive of a drop in ALC, and pre-therapy levels of CDC were not correlated with cell clearance after therapy. On day 8, ALEM-mediated in vitro CDC of circulating CLL cells had decreased to <50% of the values measured on pre-treatment samples in 6 subjects, suggesting that cells of these patients might be developing resistance to ALEM-mediated CDC. This decrease in CDC was not correlated with decreases in levels of CD52 expression on patients’ CLL cells or with increases in expression of CCP (CD35, CD46, CD55, CD59). Our findings demonstrate that even after treatment with both RTX and ALEM, CLL cells can persist in the bloodstream in a subset of patients, suggesting that some patients have circulating CLL cells that are resistant to mAb-mediated clearance and CDC due to mechanism(s) that may include loss of antigen and possibly intrinsic resistance. Disclosures: Zent: Genzyme: Research Funding; Genentech: Research Funding; Novartis: Research Funding; G.S.K.: Research Funding. Weiner:Genentech: Consultancy.
Stromal Rescue of Drug Exposed CLL Cells Can Be Overcome by the Green Tea Extract Epigallocatechin 3 Gallate
Lesnick, Connie , LaPlant, Betsy, Kay, Neil E. , Shanafelt, Tait D.

Blood | October 12, 2019 | Volume: 116 | Issue: 21 | Pages: 3610-3610

10.1182/blood.v116.21.3610.3610 Get It

Abstract Abstract 3610 Purpose Chronic Lymphocytic Leukemia (CLL) is incurable with conventional chemotherapy treatments. Nurturing of leukemic CLL B cells by marrow microenvironment appears to be one important method of chemoresistance (NEJM 2005). Epigallocatechin 3 gallate (EGCG), the major catechin in green tea, induces caspase-dependent death CLL B-cells and down regulates anti-apoptotic proteins (Mcl-1; XIAP) critical for enhanced apoptosis resistance of CLL B-cells (Blood 2004). In Phase I and II clinical testing, we found EGCG induced a decline in absolute lymphocyte count and/or lymphadenopathy in the majority of Rai stage 0-II CLL patients (JCO 2009; ASCO 2010). In these phase I/II studies, trough plasma EGCG levels as high as 8 mM were achieved. Since it does not cause myelosuppression, EGCG has the potential to be combined with other chemotherapeutic agents used for CLL. We previously reported that pharmacologically achievable plasma levels of EGCG have an additive or synergistic effect when combined with fludarabine (F), chlorambucil (C), and FC in the majority of patients (ASH 2009). In this study, we evaluated i) the effect of pharmacologically achievable doses of EGCG when combined with bendamustine (B) and ii) the ability of pharmacologically achievable doses of EGCG to overcome in vitro stromal rescue of CLL B-cells exposed to B or FC. Methods We first evaluated the effects of EGCG combined with B to establish if this partnership would be additive or synergistic. Primary CLL cells were treated with B (12.5-100 mM) with or without 4 uM EGCG. After 48 hours cells were stained with annexin/PI, and viability analyzed by flow cytometry. Data were analyzed using the CalcuSyn program (Chou & Talay method) to determine the combination index (indicating antagonistic, additive or synergistic effects). Next, we evaluated the ability of 4 mM EGCG to overcome stromal rescue of CLL cells treated with B or FC. To eliminate the cytotoxic effects of FC and B on stromal cells, we treated CLL cells with FC or B for 24 hours, washed with PBS, and then cultured these drug exposed cells directly on the HS-5 human stromal cell line with or without 4 mM EGCG for 48 hours (FC) or 24 hours (B). Cells were harvested and viability of CD19+ cells was assessed by annexin/PI staining. To specifically evaluate the ability of 4 mM EGCG to overcome stromal protection, co-culture samples in which no stromal protection was observed were excluded. Similar experiments were conducted using primary bone marrow mesenchymal stromal cells (MSC) from CLL patients (Leuk Res, 2007). In these experiments the fludarabine/chlorambucil combination was used as an approximation of fludarabine/cyclophosphamide since the active form of cyclophosphamide (4-hydroxycyclophosphamide) rapidly breaks down in aqueous buffer and is not readily available for in vitro use and. Results We previously observed additive or synergistic FC and EGCG interactions in a majority of patient samples (ASH 2009). 4 mM EGCG was less consistently beneficial when combined with increasing doses of B in the absence of stroma. Synergistic or mixed synergistic/additive effect was seen in 5 patients, mixed additive/antagonistic effects in 3, and antagonistic effects in 2. Given previously observed synergy with FC and additive/synergistic interactions with at least some B treated samples, we next explored the effects of EGCG on stromal cell rescue. Co-culture with HS-5 stromal cells significantly reduced both B and FC mediated cell death. However the addition of 4 μM EGCG significantly attenuated stromal cell rescue of CLL B-cells exposed to B and FC therapy (Fig. 1A and 1B respectively). Remarkably in the case of FC, 4 mM EGCG almost completely abrogated stromal rescue. Experiments using primary bone marrow MSC cultures from CLL patients yields similar results (n=3, data not shown). Conclusions Pharmacologically achievable doses of EGCG appear to reduce stromal rescue of CLL cells treated with B or combinations of purine nucleoside analog/alkylating agents. This occurs in the absence of detectable stromal cell kill by EGCG. These findings, coupled with the favorable toxicity profile and lack of myelosuppression in phase I/II trials of EGCG make it an attractive agent to test in combination with bendamustine or purine analogue/alkylating agent chemo-immunotherapy for patients with CLL. Disclosures: Shanafelt: Polyphenon Pharma: Research Funding.
Multi-Parameter Flow Cytometry(FC) Can Detect Proliferating Myeloma Cells After Treatment: Implications for Targeting the Myeloma Proliferative Component
Lust, John A., Kumar, Shaji , Timm, Michael, Donovan, Kathleen A., Greipp, Philip R., Morice, William G. , Morice, William George

Blood | October 12, 2019 | Volume: 116 | Issue: 21 | Pages: 4995-4995

10.1182/blood.v116.21.4995.4995 Get It

Abstract Abstract 4995 Background: Multiple myeloma results from an accumulation of monoclonal nonproliferating plasma cells arising from a small subpopulation of proliferating myeloma cells. In an effort to optimize detection of the human myeloma cell growth fraction and obviate the need for slide review, a novel FC strategy was developed combining elements of light chain restriction, surface antigen expression, and ploidy analysis. Methods: Bone marrow cells from 41 patients with plasma cell proliferative disorders were lysed with ACK and resuspended in 3% BSA. Cells were stained using a 6-color assay with anti-CD45, anti-CD38, anti-CD138, and anti-CD19. Cells were washed and 100 ul Caltag solution A was added for 15 min. Cells were washed and 100 ul of Caltag solution B, anti-kappa and anti-lambda were added for 10 min. Cells were washed and 100 ul PBS and 3 ul RNAse are added for 15 min. Cells were washed and 400 ul of a 1:1000 solution of 3uM DAPI in Tris 0.1% NP-40 was added. Cells were incubated at 4°C for 45 minutes before running on a FACSCanto instrument for ploidy determination. All patients were analyzed both by flow cytometry and the slide based plasma cell labeling index. Results: Forty-one patients were studied; 34 demonstrated a proliferative fraction and 7 had too few plasma cells for analysis after therapy. Of the 34 patients, 6 had MGUS/SMM, 5 newly diagnosed MM, 7 amyloid, and 16 were treated MM. The mean percent proliferating cells were 1.1% (range 0 – 8.6%) with PCLI and 1.4% (range 0.1 – 12.7%) by flow. The correlation between PCLI and flow gave a RSquare value of 0.54. Twelve patients with a PCLI of 0% had a flow proliferation between 0.1 – 1.4% (mean 0.49%). Treated patients received lenalidomide, dexamethasone, bortezomib, and/or autologous transplantation. All 16 treated myeloma patients with adequate plasma cells had a flow proliferation between 0.2 – 12.7% (mean 2.2%). Conclusion: Flow cytometry offers a useful way to detect the proliferative myeloma component at diagnosis and after treatment. The continued presence of proliferating myeloma cells after treatment may explain why most patients relapse and offers another important marker to monitor and cell population to target in patients with active disease. Disclosures: Kumar: Celgene: Consultancy, Research Funding; Millennium: Research Funding; Merck: Consultancy, Research Funding; Novartis: Research Funding; Genzyme: Consultancy, Research Funding; Cephalon: Research Funding.
In Patients with Light-Chain (AL) Amyloidosis Myocardial Contraction Fraction (MCF) Is a Simple, but Powerful Prognostic Measure That Can be Calculated from a Standard Echocardiogram (ECHO)
Lacy, Martha Q. , Baudi, Francis K., Kumar, Shaji , Maurer, Mathew S. , Klarich, Kyle W. , Hayman, Suzanne R. , Lust, John A., Kapoor, Prashant , Hwa, Yi L. , Zeldenrust, Steven R., Kyle, Robert A. , Grogan, Martha , Milani, Paolo , Dispenzieri, Angela , Gertz, Morie A. , Maurer, Mathew S , Leung, Nelson , Dingli, David , Lin, Yi , Go, Ronald S. , Rajkumar, S. Vincent

Blood | October 12, 2019 | Volume: 126 | Issue: 23 | Pages: 1774-1774

10.1182/blood.v126.23.1774.1774 Get It

Abstract Background: Amyloidosis is a multisystem disease with extracellular deposition of pathological insoluble beta-fibrillar proteins. Involvement of the heart is seen in more than one-half of the patients with systemic AL amyloidosis and it is the most important determinant of clinical outcome. Cardiac amyloidosis is a restrictive infiltrative cardiomyopathy in which, despite declines in stroke volume that accompany disease progression, the ejection fraction (EF) often remains preserved even in advanced stages of the disease. King et al. proposed a novel index of myocardial function, the myocardial contraction fraction (MCF), defined as the ratio of stroke volume (SV) to myocardial volume (MV). MCF is a measure of myocardial shortening, which differentiated myocardial performance in patients with similar degrees of hypertrophy and in a recent small cohort of AL amyloidosis patients appeared superior to left ventricular ejection fraction (EF) in predicting overall survival (OS). It was our goal to assess the prognostic role of MCF in a large cohort of patients with AL amyloidosis in the context of other prognostic variables. Methods: Patients seen between 4/1/1999 and 2/1/2015 were eligible for this retrospective study if they had an ECHO at the Mayo Clinic, Rochester, MN within 30 days of their AL amyloidosis diagnosis with measurements of left ventricular chamber size and wall thickness needed to calculate MCF, EF, and the presence or absence of pericardial effusion. To capture the full cohort, modeling was done first excluding Mayo (2012) staging and global averaged left ventricular longitudinal peak systolic strain (LV strain) since limited numbers of patients had these studies, 342 and 294, respectively. Thresholds of continuous variables were chosen based on receiver operator curves targeting death at 1-year. Cox proportional hazards analysis was used to identify factors that were prognostic for OS. Statistical analyses were done using JMP 9.0 (SAS, Cary, NC). Results: Among the 722 patients satisfying entry criteria,median age was 64 years (range 32-94) and 66% were male. The best cutoff for MCF was 21% (sensitivity: 74%, specificity: 60%; AUC=0.699) and distinguished two groups with different OS (median 53 vs. 9 months, P<0.0001; Figure). On univariate analysis the baseline ECHO variables predicting OS were interventricular septum thickness (IVS) >12 mm (RR 1.8, P=0.0002), EF <60% (RR 1.7), MCF ≤21% (RR 2.1), and presence of pericardial effusion (RR 2.0), all with P<0.0001. On multivariate MCF ≤21% (RR 1.6, P <0.0001), EF <60% (RR 1.4, P=0.0007) and the presence of pericardial effusion (RR 1.3, P=0.002) were independent predictors of OS. Additional modeling was done with the subset of 342 patients who were assessable for Mayo (2012) staging, (i.e. measurements of immunoglobulin free light chain, NT-proBNP, and troponin T). On univariate analysis, patients with a Mayo (2012) stage ≥ 3 had a RR 2.1, p<0.0001. On multivariate, only MCF ≤21% (RR 1.5, P =0.01), Mayo (2012) stage ≥ 3 (RR 1.5, P=0.01) and EF<60% (RR 1.7, P=0.0006) were independent prognostic determinants. Finally, we addressed LV-strain among the 294 patients in whom the study was performed. There was a significant correlation between MCF and LV strain (rho =-0.86, P<0.0001). On univariate, LV-strain less negative than -13 generated a RR of 2.3, p<0.0001. In contrast to the model containing MCF, on LV-strain multivariate, EF was no longer significant, but LV-strain less negative than -13 (RR 2.0, P=0.008) and Mayo (2012) stage ≥ 3 (RR 2.0, P=0.008) predicted independently OS. Conclusions: MCF ≤21% identified a subgroup of patients with a high mortality risk, and it was independent of the Mayo (2012) staging but highly correlated with LV strain. An advantage of MCF, which is a novel volumetric measurement of the left ventricular chamber, is that, unlike LV-strain, MCF is simple to calculate from routine ECHO measures. Figure 1. Overall survival of 722 patients according to MCF<21%. Figure 1. Overall survival of 722 patients according to MCF<21%. Disclosures Kumar: AbbVie: Research Funding; Celgene: Research Funding; Janssen: Research Funding; Skyline, Noxxon: Honoraria; Celgene, Millenium, Sanofi, Skyline, BMS, Onyx, Noxxon,: Other: Consultant, no compensation,; Sanofi: Research Funding; Millenium/Takeda: Research Funding; Onyx: Research Funding.
High Quality Bone Marrow Core Biopsy and Aspiration (BMBX) Procedures Can Be Performed by a Nurse Led Team Using the OnControl Battery Powered Bone Marrow Biopsy System
Cherington, Chad, Robetorye, Ryan S. , Anderson, Eryn M, Beuschel, Trisha L, Gunderson, Jody D, Maningo-Salinas, Marie J., Valdez, Riccardo, Gunderson, Jody

Blood | October 11, 2019 | Volume: 118 | Issue: 21 | Pages: 4743-4743

10.1182/blood.v118.21.4743.4743 Get It

Abstract Abstract 4743 Background: BMBX procedures are traditionally performed by physicians, NPs, or PAs using a manual method. It is uncommon for nurses to perform these procedures, and even more rare for nurses to perform them using non-traditional techniques, such as the battery-powered system (OnControl, Vidacare, Shavano, TX). In this study, we report our nurse-led BMBX team experience using OnControl to collect diagnostic BMBX samples. Patient care and safety, team satisfaction, and specimen quality were evaluated. Methods: A team of nurses trained to perform BMBX procedures on sedated and non-sedated patients completed 94 procedures using OnControl and established SOPs. All nurses completed a questionnaire aimed at assessing the patient experience during and after the procedure and overall nurse satisfaction with OnControl. Specimen quality was graded by 3 physicians and compared to 25 specimens obtained by the same nursing team using traditional methods. Bone core specimens were graded based on core length and the presence/absence of artifacts. Biopsies had to be >1 cm or >1.5 cm to qualify good or excellent, respectively. Aspirates were similarly evaluated taking into account the presence/absence of spicules on stained smears. Results: Patient Care & Safety: The majority (86.2%) of patients who underwent a BMBX procedure during the study were outpatients, and minimal sedation was used in 94.7%. Most patients (76.6%) had a prior BMBX using the traditional method. In 94 patients evaluated, pre-procedure pain was 0 (0-10 scale) in 72 (76.5%) while 21 (22.3%) reported pain up to 5 just before the procedure (avg=2). The post-procedure pain score in the same patients was 0 in 78 (83%) and up to 4 in six (6%) (avg=1). No patients had post-procedure bleeding or complications requiring medical care. Seventy patients were reached 24 hrs post-procedure: 33 (47%) reported no pain and 37 (53%) reported pain up to 8 (avg=2.5). Nurse BMBX Team Satisfaction: Team members reported 100% satisfaction with the process of inserting the OnControl biopsy needle through soft tissues and acquiring a core biopsy. The nurses reported having satisfactory control of the depth of needle through the cortex and into the medullary space using the needle guide 95% of the time. Team members were satisfied with the ease of obtaining an aspirate 93% of the time. Nearly all (95%) nurses felt improved ergonomics using the battery-powered driver compared to the manual method. The nurses reported that OnControl was easy to use, with 83% of them obtaining a core biopsy on their first attempt. All nurses indicated they would use OnControl over the manual method if given the choice. Specimen Quality: H&E-stained bone core biopsy slides and W-G-stained aspirate smears from 83/94 specimens collected using OnControl were reviewed and graded. All but two (2.4%) of the bone core specimens were adequate for diagnosis. Of adequate samples, 45.8% were excellent, 12% good, and 39.8% fair. Aspiration artifact was seen in 18/83 (21.6%) of cores, and that artifact was the reason for a downgrade to fair quality in 17/18 (94%). Extra aspirate material for research was collected in 7/18 with fair quality bone core biopsies. Similar grading applied to 25 core biopsy samples collected using the manual method revealed 44% of cores to be excellent, 20% good, 32% fair, and 4% poor. The average core length using OnControl and the traditional method was 1.6 cm and 1.7 cm, respectively. Five of 83 (6%) aspirates obtained using OnControl were poor quality due to lack of bone marrow cells. Of the remaining aspirates, 54.2% were excellent, 20.5% good, and 19.2% fair. Factors related to bedside technique caused a downgrade in 10/16 samples graded as fair and 5/17 samples graded as good. Aspirates obtained by the standard method were graded as 52% excellent, 28% good, 12% fair, and 8% poor. Conclusions: Trained nurses can safely and effectively perform BMBX procedures using traditional methods as well as novel techniques such as the OnControl battery-powered driver system. In the hands of experienced individuals, OnControl can consistently yield high-quality BMBX specimens. Aspiration artifact was the most common flaw found in bone cores obtained with OnControl, but it was usually focal and did not hinder interpretation. When artifact associated with technical aspects out of the control of the BMBX operator was excluded, the OnControl needle produced good-excellent aspirate in 87% of patients. Disclosures: No relevant conflicts of interest to declare.
Apoptosis Rates in Myeloma Cells Can Be Significantly Affected by CD138 Sorting and by the Specific Method Used To Detect Apoptotic Cells.
Kimlinger, Teresa K. , Kline, Michael, Timm, Michael, Haug, Jessica, Kumar, Shaji , Rajkumar, S. Vincent , Witzig, Thomas E.

Blood | October 11, 2019 | Volume: 108 | Issue: 11 | Pages: 3442-3442

10.1182/blood.v108.11.3442.3442 Get It

Abstract Background: The clonal plasma cells in multiple myeloma have relatively low rates of apoptosis. We have previously shown that the apoptotic rates of the plasma cells have prognostic value in these patients. However, several methods are used both for targeting the myeloma cells for study as well as for detection of apoptosis in these cells. It is not clear which method is optimal for studying apoptotic rates of plasma cells from primary patient samples. We examined two different ways of studying the plasma cells, namely CD138 magnetic bead based positive selection of myeloma cells (sorted) and gating on the plasma cells in whole bone marrow (unsorted) using CD38/CD45 expression patterns. Additionally, we compared two different methods of identifying apoptotic plasma cells. Methods: Paired samples processed by two different methods were studied. The bone marrow aspirate samples were initially processed using ACK lysis to remove the red cells. The samples were then studied using flow cytometry (unsorted sample) or subjected to a second step of magnetic bead based separation of myeloma cells based on CD138 expression (sorted sample). Each of the samples was studied using Annexin/PI and Apo 2.7 expression to identify the plasma cells undergoing apoptosis. Plasma cells were identified in the unsorted samples by virtue of their CD38/CD45 expression. Samples were studied at collection and after 48 hours of culture. Results: At collection, the median percentages of cells considered apoptotic by annexin/PI (Annexin pos, PI neg) were higher than that detected by the Apo 2.7 method (Apo 2.7 + cells), for both sorted (6.5% vs. 1.5%) and unsorted cells (26% vs. 10%). However, after 48 hours of culture the percentage of apoptotic cells detected using the Apo 2.7 method were higher than that by Annexin/PI for both sorted (22.5% vs. 14.5%) and unsorted cells (43.5% vs. 10%). When the 48 hr study was compared with the initial study, percent apoptotic cells detected by Apo 2.7 had increased at 48 hrs for both sorted and unsorted cells. However, the percentage of apoptotic cells by annexin/PI had decreased in the unsorted cells at 48 hrs compared to initial study. The sorted samples had an overall increase in apoptosis at 48 hours as measured by annexin/PI. We then looked at the percentage of apoptotic cells detected by either method on initial study and compared the sorted cells and unsorted cells. Using either method, the percentage of apoptotic cells was significantly less (P=0.01; paired t-test) among the sorted cells compared to the unsorted cells. Conclusion: Previous studies have shown that CD138 expression is lost from PCs as they enter apoptosis. Here we show in paired samples that the percentage of apoptotic myeloma cells significantly decreases following CD138 sorting. CD138 sorting should not be used when studying apoptosis of myeloma cells in patient samples. Use of unsorted cells also allows for examination of the effects of interventions on other cell populations as well. When serial studies of apoptosis are done with unsorted samples, we recommend using Apo 2.7 rather than Ann/PI, since the percentage of apoptotic cells by Ann/PI expression actually appear to decrease with time in culture, thus making it difficult to assess effects of intervention such as in drug treatment studies. We hypothesize that this is due to an artificially high level of Annexin positivity at the initial study that might be brought on by non-specific damage of the membranes secondary to cell processing.