Bradwell, A.R.

Joyce, Kelsey E., Catherine A. Campbell, Arthur R. Bradwell, Samuel J.E. Lucas, Christopher T. Lewis, Rebekah A.I. Lucas, and Mark Edsell; for the Birmingham Medical Research Expeditionary Society (BMRES). The environmental impact of a high-altitude medical research expedition. High Alt Med Biol. 26:140–147, 2025. Introduction: Scientists must begin examining the environmental cost(s) of their research. The purpose of this study was to evaluate a component of the environmental impact of a high-altitude medical research expedition by totaling the carbon dioxide (CO 2 ) emissions calculated from as many direct and indirect sources as possible. Methods: Eighteen individuals flew from London to Bagdogra (via Delhi), and then drove onward to Lachung (via Gangtok) where they began their ascent on foot to 4,800 m (Kanchenjunga National Park, Sikkim). Several research experiments were conducted throughout the expedition, which required use of a laboratory centrifuge, solid CO 2 (specimen storage), rechargeable laptop computers and battery-powered oximeters. International Civil Aviation Organization calculators estimated aviation CO 2 production. Land emissions were calculated for Mahindra vehicles. Solid waste was weighed and CO 2 emissions estimated for its incineration. Results : Total CO 2 emissions equated to ∼16.7 tonnes from the following sources: air and land transportation of expedition team (87.3%); sublimation and transportation of solid CO 2 (7.7%), waste incineration (0.58%), generator transportation and gasoline (12 l) combustion (0.48%), and battery transportation (3.3%). Conclusions : Air travel contributed the most to the overall environmental cost of the research expedition. Further investigation is required to contextualize these findings in relation to lab-based alternative(s).

Abstract Background: Monoclonal gammopathy of undetermined significance (MGUS) is a premalignant plasma cell disorder that carries a 1% per year risk of progression to multiple myeloma (MM) or related malignancy. The prevalence and natural history of MGUS, in which by definition intact immunoglobulin heavy chain (IgH) is expressed, has been well described. However, up to 20% of myeloma (MM) is characterized by complete lack of IgH expression (Light-chain MM); the prevalence of a corresponding precursor entity, light chain MGUS (LC-MGUS) has not been determined. We report the first prevalence estimates of LC-MGUS in the general population from a large, well-defined geographic population using modern laboratory techniques. Methods: The cohort for this study was derived from one previously assembled by us to estimate the prevalence of MGUS (N Engl J Med2006;354:1362-9). The original cohort used to estimate the prevalence of MGUS consisted of 21,463 of the 28,038 enumerated residents aged 50 or over of Olmsted County Minnesota as of January 1, 1995. The sensitive serum free light chain (FLC) assay (The Binding Site Limited, Birmingham, U.K.) was performed on stored serum samples from these 21,463 persons. IgH expression was determined by immunofixation on all FLC results that had an abnormal kappa/lambda ratio (<0.26 or >1.65). LC-MGUS was defined as the presence of an abnormal FLC ratio and a negative immunofixation for IgH expression. Results: Adequate stored serum samples were available in 20,733 (97%) of the 21,463 persons. To date, the FLC assay has been performed and results were available for analysis on samples from 16,637 persons. An abnormal FLC ratio was observed in 572 persons. IgH expression was detected in 255 of these cases on immunofixation; these persons are considered as having MGUS, and were excluded from the estimation of LC-MGUS prevalence. This resulted in 317 persons out of 16,637 who had an abnormal FLC ratio without evidence of IgH expression, resulting in an estimated prevalence of LC- MGUS of 2%. Of the 317 cases of LC-MGUS identified in this study, 217 were kappa and 100 were lambda; in 35 cases the presence of the corresponding monoclonal light chain was apparent on immunofixation. The median age of the cohort of LC-MGUS was 62 years; males=151, females =166. The involved FLC level ranged from 0.118–270.0 mg/dL. The FLC ratio ranged from 0.014–0.253 (lambda) and 1.67–511.01 (kappa). So far, progression to multiple myeloma has occurred in 4 patients, a rate much higher than what is expected based on the prevalence of myeloma in the general population. Two additional patients have developed CLL. Conclusions: LC-MGUS is prevalent in 2% of the general population aged 50 years of age or older. The natural history of this disorder needs to be determined.

Abstract Background: The free light chain (FLC) assay allows a nephelometric measurement of this free kappa and lambda light chains that circulate as monomers or dimers, not bound to the immunoglobulin heavy chain. Estimation of the free light chain levels and their ratio has utility in screening, prognostication and treatment response assessment in multiple myeloma, and is particularly useful in light chain myeloma. Previous studies have suggested that absence of a functional rearrangement on at least one of the IgH allele is the basis of light chain myeloma. Translocations involving the immunoglobulin heavy chain (IgH) locus on chromosome 14 can be detected using FISH in over half of the patients with myeloma. We hypothesized that presence of an IgH translocation may be associated with compromised production of heavy chains and leads to unbalanced, excess production of clonal light chain. Methods: From February 1988 to May 1992, 653 patients with previously untreated multiple myeloma were enrolled on the phase III clinical trial E9486. Serum free light chains were run on stored sera obtained at baseline in 495 patients as part of a previous study. Among these patients, 314 patients were previously studied using FISH for presence or absence of IgH translocations, p53 abnormalities and deletion 13 and were included in the current analysis. Results: The median difference between the involved and uninvolved FLC (FLCdiff) was higher among the group of patients with any IgH translocation abnormality compared to those with none (Figure 1). This was particularly evident among the patients with a t(14;16) who had the highest FLCdiff. In a multivariate analysis, we examined if the prognostic value seen with FLCdiff was independent of the presence of IgH translocations t(4:14) and t(14;16), which are associated with a worse outcome. The presence of t(4;14) or t(14;16) was associated with FLCdiff groups using a cutoff point of 185, with 13% of those with FLCd ≤185 and 27% of those with FLCd > 185 having the translocations (P= 0.008). At the cutoff value of 185, the prognostic value of the FLC-diff on progression free and overall survival appears to be independent of these high risk IgH translocations (P-value=0.03 and 0.003, respectively for PFS and OS) We then examined the prognostic value of the FLC-diff in the group of patients without these two high risk abnormalities and were able to confirm that they remained prognostic for PFS (P=0.009) and OS (p=0.005). However, among the group of patients with either of the two high risk IgH abnormalities, FLCdiff estimate added little to assessment of their outcome (P=0.97 and 0.20, respectively for PFS and OS). Conclusion: Elevated free light chain levels are associated with presence of IgH translocations and these patients are more likely to harbor the high risk genetic abnormalities. Routine FISH testing for patients with newly diagnosed myeloma will allow us to confirm these and allow better risk stratification of the patients. Additional work needs to be done to help us better understand the molecular basis for unbalanced light chain excretion by myeloma cells and the current finding of the association with IgH translocation abnormalities should form the basis for this work. Figure 1. Distribution of FLC ratio (inv vs. uninv) and FLC difference (inv − uninv) among patients. Solid squares represent patients with t(4;14) or t(14;16) or t(11;14) or other 14q32 translocation; open circles represent patients without t(4;14), t(14;16), t(11;14) and any other 14q32 translocations. The horizontal dashed lines refer to FLC ratio original values of 100 and 1000, and vertical dashed lines refer to FLC difference original values of 10 and 100. Solid line indicates significant association (P<=0.05) between the dichotomized FLC groups and translocation status. Figure 1. Distribution of FLC ratio (inv vs. uninv) and FLC difference (inv − uninv) among patients. Solid squares represent patients with t(4;14) or t(14;16) or t(11;14) or other 14q32 translocation; open circles represent patients without t(4;14), t(14;16), t(11;14) and any other 14q32 translocations. The horizontal dashed lines refer to FLC ratio original values of 100 and 1000, and vertical dashed lines refer to FLC difference original values of 10 and 100. Solid line indicates significant association (P<=0.05) between the dichotomized FLC groups and translocation status.

AbstractBackground: The detection of monoclonal free light chains (FLCs) is an important diagnostic aid for a variety of monoclonal gammopathies and is especially important in light-chain diseases, such as light-chain myeloma, primary systemic amyloidosis, and light-chain-deposition disease. These diseases are more prevalent in the elderly, and assays to detect and quantify abnormal amounts of FLCs require reference intervals that include elderly donors.Methods: We used an automated immunoassay for FLCs and sera from a population 21–90 years of age. We used the calculated reference and diagnostic intervals to compare FLC results with those obtained by immunofixation (IFE) to detect low concentrations of monoclonal κ and λ FLCs in the sera of patients with monoclonal gammopathies.Results: Serum κ and λ FLCs increased with population age, with an apparent change for those >80 years. This trend was lost when the FLC concentration was normalized to cystatin C concentration. The ratio of κ FLC to λ FLC (FLC K/L) did not exhibit an age-dependent trend. The diagnostic interval for FLC K/L was 0.26–1.65. The 95% reference interval for κ FLC was 3.3–19.4 mg/L, and that for λ FLC was 5.7–26.3 mg/L. Detection and quantification of monoclonal FLCs by nephelometry were more sensitive than IFE in serum samples from patients with primary systemic amyloidosis and light-chain-deposition disease.Conclusions: Reference and diagnostic intervals for serum FLCs have been developed for use with a new, automated immunoassay that makes the detection and quantification of monoclonal FLCs easier and more sensitive than with current methods. The serum FLC assay complements IFE and allows quantification of FLCs in light-chain-disease patients who have no detectable serum or urine M-spike.

Abstract Background: Monoclonal gammopathy of undetermined significance (MGUS) affects 3% of persons age 50 yrs or greater. Reliable predictors of progression of MGUS to myeloma or related malignancy are needed. We hypothesized that the presence of monoclonal unbound (free) kappa or lambda immunoglobulin light chains in MGUS, as detected by an abnormal serum kappa/lambda free light chain (FLC) ratio would indicate clonal evolution in the neoplastic plasma cell and increase risk of progression to malignancy. Methods: Patients (pts) from Southeastern Minnesota with MGUS seen at the Mayo Clinic from Jan 1, 1960 through Dec 31, 1994 who had baseline serum samples collected and stored at the time MGUS was first recognized were studied. Free kappa and lambda chains were measured using the serum FLC assay (FREELITETM, The Binding Site Ltd). Results: Of 1384 pts with MGUS during the defined time period, baseline serum samples obtained within 30 days of diagnosis of MGUS were available in 1148 pts. At a median follow-up of 15 yrs, malignant progression has occurred in 87 (7.6%) pts: myeloma (53 pts), IgM lymphoma (17), primary amyloidosis (6), macroglobulinemia (6), chronic lymphocytic leukemia (3) and plasmacytoma (2). An abnormal kappa/lamda FLC ratio (kappa/lambda ratio <0.26 or >1.65) indicating presence of monoclonal FLC was detected in 379 (33%) pts. In a Cox proportional hazards model, the risk of progression in pts with an abnormal kappa/lamda FLC ratio was significantly higher (hazard ratio 3.5, 95% CI 2.3–5.5; p<0.001) compared to pts with a normal ratio. After adjusting for the size of the serum monoclonal (M) protein by multivariate analysis, the hazard ratio was only slightly reduced to 2.8, p<0.001. The risk of progression to myeloma or related malignancy at 10 years was 17% with an abnormal kappa/lambda FLC ratio versus 5% with a normal ratio; corresponding rates at 20 years were 35%, and 13%, respectively. MGUS pts with both an abnormal serum FLC ratio and high serum M protein had a risk of progression at 20 years of 46% (high-risk), versus 26% with one of two risk factors (intermediate-risk) and 7% with no risk factors (low-risk) (Table). The true life-time (28 year) risk of myeloma or related malignancy in the low-risk group was only 5.3% when other competing causes of death were taken into account. Conclusions: Presence of monoclonal FLC in the serum as detected by an abnormal kappa/lamda FLC ratio is a major independent risk factor for progression of MGUS to myeloma or a related malignancy. The new risk-stratification identifies a low-risk subset with a remarkably small life-time risk of progression, a finding of significant importance for the management of MGUS. Risk-stratification of MGUS using the size of the serum M spike and free light chain ratio Risk Group No. of patients Hazard ratio Absolute risk of progression at 20 years Low-risk (Serum M protein <1.5 gm/dL and normal FLC ratio [0.26–1.65]) 606 1 7% Intermediate-risk (Either risk factor present) 373 3.5 26% High-risk (Serum M protein >/=1.5 gm/dL and abnormal FLC ratio [<0.26 or >1.65]) 169 6.8 46%

Abstract Abstract 3893 Background: When screening for clonal disease, the kappa (k) to lambda (l) FLC ratio (FLC-R) is employed to correct for both impaired catabolism (renal function) and non-specific production (generalized immune overstimulation). This adjustment makes it possible to identify patients with relative imbalances between k and l levels, which typically qualifies for clonal excess and has been of value in screening for and prognosticating in patients with most clonal plasma cell disorders. We previously performed a population-based study among Olmsted County residents to ascertain the prevalence of monoclonal gammopathy of undetermined significance (MGUS) and light chain MGUS. We hypothesized that by using this cohort, we could identify whether the FLC assay provides information that would be prognostic in a general population of people 50-years and older. Methods: The Olmsted MGUS prevalence cohort was comprised of 21,463 of the 28,038 enumerated individuals over the age of 50 who were living Olmsted between 1/1/95 and 11/21/2003. The final sample size of individuals for the present study was 15839 due to patient losses secondary to blinding, inadequate sample to perform the FLC assay, and known MGUS or LC-MGUS. For the multivariate analyses, another 772 were excluded due lack of coincident creatinine measurement. The FLC measurements were performed using the FLC assay (Binding Site, Birmingham, UK). The respective reference ranges for k FLC and l FLC are 0.33–1.94 mg/dL and 0.57–2.63; therefore, the reference range for the sum of k and l FLC (S FLC) is 0.90–4.57 mg/dL. Survival time was calculated from the time of sample ascertainment. Results: Forty-five percent of the cohort was male. The median age was 63 years (range 50, 109). On univariate analysis, the hazard ratio for death for those patients with the highest decile of S FLC relative to the other 90% of patients in the cohort was 4.3 (95%CI 4.01, 4.62), Figure 1. Because serum immunoglobulin FLC rise with age and with renal insufficiency, a multivariate analysis was performed to exclude the possibility that S FLC was merely a surrogate for these other parameters. Table 1 shows both univariate and multivariate risk for death. With these other variables included, the hazard ratio for death with highest S FLC decile was lower, but remained significant; hazard ratio, 2.0 (95%1.88, 2.2). Conclusions: The finding that S FLC above the normal range (i.e. highest decile) is associated with inferior overall survival among individuals above the age of 50, excluding patients with known MGUS or LC-MGUS, is important and merits further investigation. Although there is an association between S FLC, renal function, gender, and age, excess risk of death still exists after adjusting for these risk factors on multivariate analysis. The mechanism by which S FLC predicts for outcomes is uncertain, but one could postulate that conditions resulting in overactivation of the immune system contributes to excess risk of death. Whether the S FLC adds above and beyond other conventional inflammatory markers like ESR or CRP cannot be determined by the present study, but is worthy of further investigation. Disclosures: Dispenzieri: Celgene: Honoraria, Research Funding; Binding Site: Honoraria. Off Label Use: No FDA approved indication. Kumar:Celgene: Consultancy, Research Funding; Millennium: Research Funding; Merck: Consultancy, Research Funding; Novartis: Research Funding; Genzyme: Consultancy, Research Funding; Cephalon: Research Funding. Mead:Binding Site: Employment. Bradwell:Binding Site: Equity Ownership, Patents & Royalties.

Abstract Abstract 1788 Poster Board I-814 Background Clinically available prognostic factors for progression of MGUS to myeloma include the size of the M-spike, heavy chain isotype, and free light chain (FLC) K/L ratio. The combined use of these variables provides approximately a 10-fold difference in risk for progression. The highest risk group, however, still has only a 27% twenty year risk of progression. Therefore, additional predictors of progression are needed. Suppression of uninvolved immunoglobulins has been an inconsistent predictor of progression. The novel Hevylite” assay measures concentrations of each isotype-specific immunoglobulin heavy light chain (HLC) pair (i.e., IgG kappa, IgG lambda, IgA kappa, IgA lambda) and enables us for the first time to determine if suppression of isotype-specific Ig of the opposite HLC is occurring and if it is predictive of progression of MGUS to myeloma. We studied the prognostic value of isotype specific HLC suppression of uninvolved immunoglobins as a predictor of progression in MGUS. Methods: Total immunoglobulins were quantitated by immunonephelometry, and suppression was defined as concentrations less than the lower limit of the reference range. HLC concentrations were quantitated with Hevylite reagents (The Binding Site, Ltd). The antibodies used in this investigational nephelometric assay span epitopes in the junctional areas between the HLC constant regions. Based on reference ranges for GK (407-1130 mg/dL), GL (188-583 mg/dL), AK (55-292 mg/dL), and AL (39-249 mg/dL) that we derived from 276 normal samples, we compared the proportion of patients who had isotype specific suppression of the opposite HLC pair among 30 patients with MGUS who progressed to myeloma versus 36 patients who had not progressed over a similar follow-up period. To confirm the relationship of isotype specific HLC pair suppression compared to suppression of uninvolved immunoglobulins of other heavy chain classes, we tested a second cohort of stored samples from 50 IgG and 14 IgA MGUS patients prior to the development of MM. Results In the initial samples from 36 IgG MGUS patients who had stable disease, 6% had suppression of uninvolved intact immunoglobulins of IgA and/or IgM, while 22% had isotype specific suppression of the opposite HLC pair (i.e., IgG lambda suppressed in IgG kappa MGUS, and vice versa). In contrast, in baseline samples from 30 IgG MGUS patients who eventually progressed to myeloma or related malignancy, 7% had suppression of IgA and/or IgM, while 40% had isotype specific suppression of the opposite IgG HLC pair. Thus, HLC pair suppression was more frequent than suppression of Igs from other heavy chain classes, and MGUS patients who eventually progressed had a 2-fold higher rate of isotype specific HLC pair suppression than stable MGUS patients. These findings were confirmed independently on a second cohort of patients who progressed to myeloma 5-10 years after blood collection. In samples from 50 IgG MGUS patients, 42% had suppression of Igs of other heavy chain classes, while 80% had suppression of the isotype specific HLC by the Hevylite assay. In the last samples prior to progression, the suppression of heavy chain classes increased to 60%, while isotype specific HLC suppression rose to 90%. Interestingly, the 14 IgA patients had equivalent suppression of gamma or mu heavy chain classes as compared to the HLC pairs, with 50% of the patients having suppression in the initial sample and 79% in the last sample prior to MM. Conclusion Our data suggest that suppression of the opposite IgG HLC pair is a predictor of patients destined for progression. Isotype specific HLC pair suppression of this nature is more frequent in these patients (more sensitive) than suppression of other heavy chain classes. We were not able to demonstrate a similar effect in IgA MGUS. Larger studies are underway to determine if HLC pair suppression is independent of M-spike quantitation, heavy chain isotype, and FLC ratio. Biologically, our findings suggest that clonal IgG plasma cells are able to suppress other IgG producing non-clonal plasma cells far more effectively than IgA or IgM secreting cells, and this occurs more frequently with cells that will eventually undergo malignant transformation. Disclosures Bradwell: The Binding Site Group Ltd: Equity Ownership.

AbstractThe immunoglobulin free light chain (FLC) assay is an invaluable tool for following patients with oligosecretory plasma cell dyscrasia. Baseline values have also been shown to be prognostic in all plasma cell disorders tested. A looming question, however, is the role it should play in following myeloma patients with disease that is measurable using serum and urine electrophoresis. We used the data and stored samples from a mature Eastern Cooperative Oncology Group clinical trial (E9486) to assess serum levels of FLC at baseline and after 2 months of alkylator-based therapy. For serial determinations, the absolute level of involved serum FLC or the difference of the involved and uninvolved FLC is preferred over the ratio of involved to uninvolved FLC. FLC response after 2 months of therapy was superior to early M-protein measurement to predict overall response. The ideal cut-point for FLC change appears to be between 40% and 50% reduction. The correlation between serial measurements of serum FLC and urine M-protein is inadequate to abolish the serial 24-hour urine protein. Although baseline values of FLC are prognostic in newly diagnosed myeloma patients, serial measurements do not appear to have added value in patients who have M-proteins measurable by electrophoresis.

Abstract We hypothesized that the presence of monoclonal free kappa or lambda immunoglobulin light chains in monoclonal gammopathy of undetermined significance (MGUS), as detected by the serum free light chain (FLC) assay increases the risk of progression to malignancy. Of 1384 patients with MGUS from Southeastern Minnesota seen at the Mayo Clinic from 1960 to 1994, baseline serum samples obtained within 30 days of diagnosis were available in 1148. At a median follow-up of 15 years, malignant progression had occurred in 87 (7.6%) patients. An abnormal FLC ratio (kappa-lambda ratio &lt; 0.26 or &gt; 1.65) was detected in 379 (33%) patients. The risk of progression in patients with an abnormal FLC ratio was significantly higher compared with patients with a normal ratio (hazard ratio, 3.5; 95% confidence interval [CI], 2.3-5.5; P &lt; .001) and was independent of the size and type of the serum monoclonal (M) protein. Patients with an abnormal serum FLC ratio, non–immunoglobulin G (non-IgG) MGUS, and a high serum M protein level (≥ 15 g/L) had a risk of progression at 20 years of 58% (high-risk MGUS) versus 37% with any 2 of these risk factors (high-intermediate risk), 21% with one risk factor (low-intermediate risk), and 5% when none of the risk factors were present (low risk).