Abstract The incidence of multiple myeloma (MM) is twice as high in blacks compared with whites. MM consists of several different cytogenetic subtypes, with differing presentations, response to therapy, and prognosis. The studies that have characterized the distribution of the primary cytogenetic abnormalities by fluorescence in-situ hybridization (FISH) testing have been primarily conducted in white populations, and more data are needed on whether the distribution of these cytogenetic abnormalities differs in black compared with white MM patients, and to determine if the increased prevalence of MM in blacks is related to specific subtypes of the disease. In this multi-center study, we examined four common clinically assessed cytogenetic subtypes (t(11;14), t(4;14), del13q, and del17p) at time of MM diagnosis in 245 black patients from 3 clinics who had prior FISH testing available in medical records. We compared the prevalence of these subtypes with our previously characterized Mayo Clinic cohort which was all Caucasian (n=484). The t(11;14) translocation was seen in 9 of 245 (4%) black patients with MM; this was significantly lower than the rate of t(11;14) translocations seen in white patients from Mayo Clinic (18%), p < 0.0001). In contrast to t(11;14), the prevalence of the t(4;14) translocation across the two groups was similar (p= 0.92). We conclude that the prevalence of t(11;14) translocation is significantly lower in blacks with myeloma compared with whites. Our findings suggest that the distribution of cytogenetic subtypes found in MM may differ significantly by race, and further studies assessing differences in the prevalence of other primary cytogenetic abnormalities such as trisomies, t(6;14), t(14;16), and t(14;20) are needed. Furthermore, these results support the hypothesis previously put forth that there are several different subtypes of multiple myeloma that may be defined by the major cytogenetic translocations. Since these results differ from those previously reported (Baker et al 2013, Blood), we are conducting further analyses of these data to examine possible factors that could account for the differential association of translocation by race, including probes used. Citation Format: Alexandra Joelle Greenberg, Sunita Philip, Agne Paner, Sylvia Velinova, Ashraf Badros, Rosalind Catchatorian, Dirk Larson, Rhett Ketterling, Robert A. Kyle, Shaji Kumar, Celine M. Vachon, S. Vincent Rajkumar. Evidence of decreased prevalence of the t(11;14) translocation in black patients with multiple myeloma: A multi-center study. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 272. doi:10.1158/1538-7445.AM2014-272
Soluble suppression of tumorigenicity 2 (sST2), but not galactin‐3, adds to prognostication in patients with systemic AL amyloidosis independent of NT‐proBNP and troponin T
American Journal of Hematology | March 9, 2015 | Volume: 90 | Issue: 6 | Pages: 524-528
AbstractBACKGROUNDThe use of electrophoresis to monitor monoclonal immunoglobulins migrating in the β fraction may be difficult because of their comigration with transferrin and complement proteins.METHODSImmunoassays specific for IgGκ, IgGλ, IgAκ, IgAλ, IgMκ, and IgMλ heavy/light chain (HLC) were validated for use in the clinical laboratory. We assessed sample stability, inter- and intraassay variability, linearity, accuracy, and reference intervals for all 6 assays. We tested accuracy by verifying that the sum of the concentrations for the HLC-pairs accounted for the total immunoglobulins in each of 129 healthy sera, and that the HLC-pair ratios (rHLCs) were outside the reference interval in 97% of 518 diagnostic multiple myeloma (MM) samples.RESULTSWe assessed diagnostic samples and posttreatment sera in 32 IgG and 30 IgA patients for HLC concentrations, rHLC, and total immunoglobulins and compared these nephelometry results with serum protein electrophoresis (SPEP) and immunofixation electrophoresis (IFE). In sample sets from patients with IgG MM, the sensitivity of SPEP was almost the same as for rHLC, and no additional advantage was conferred by running HLC assays. In pre- and posttreatment samples from patients with IgA MM, the SPEP, rHLC, and IFE identified clonality in 28%, 56%, and 61%, respectively. In addition, when M-spikes were quantifiable, the concentration of the involved HLC was linearly related to that of the SPEP M-spike, with a slope near 1.CONCLUSIONSThe use of IgA HLC assays for monitoring β-migrating IgA monoclonal proteins can substitute for the combination of SPEP, IFE, and total IgA quantification.
Protein Electrophoresis and Immunofixation for the Diagnosis of Monoclonal Gammopathies
Abstract Objective To determine the prognosis of patients with non‐secretory myeloma. Methods We studied 124 patients diagnosed with multiple myeloma who had no monoclonal protein detected on serum and urine immunofixation at diagnosis and on all subsequent follow‐up testing (non‐secretory myeloma). The overall survival ( OS ) of patients with non‐secretory myeloma was compared with 6953 patients with typical myeloma seen during the same time period in whom a monoclonal protein was detected at the time of diagnosis. Results One hundred and twenty‐four patients met criteria for non‐secretory multiple myeloma. The median follow‐up was 102 months (range, 1–204 months). The median progression‐free survival with initial therapy was 28.6 months, and the median OS was 49.3 months. There was a significant improvement in OS since 2001; median survival 43.8 months (prior to 2001) vs. 99.2 months (2001–2012), P < 0.001. OS was superior in patients with a normal baseline FLC ratio ( n = 10) compared to patients with an abnormal ratio ( n = 19), medians not reached in both groups. Prior to 2001, OS was similar in non‐secretory myeloma ( n = 86) and secretory myeloma ( n = 4011), median 3.6 vs. 3.5 yr, respectively, P = 0.63. However, among patients diagnosed between 2001 and 2012, OS was superior in non‐secretory myeloma ( n = 36) compared to secretory myeloma ( n = 2942), median 8.3 vs. 5.4 yr, respectively, P = 0.03. Conclusions Non‐secretory myeloma is an uncommon subtype of multiple myeloma. In the last decade, there has been an improvement in the survival of non‐secretory myeloma and appears superior to secretory myeloma.