Final Results From a Phase I Trial and Expansion Cohorts of Cabozantinib and Nivolumab Alone or With Ipilimumab for Advanced/Metastatic Genitourinary Tumors.

PURPOSE: Cabozantinib and nivolumab (CaboNivo) alone or with ipilimumab (CaboNivoIpi) have shown promising efficacy and safety in patients with metastatic urothelial carcinoma (mUC), metastatic renal cell carcinoma (mRCC), and rare genitourinary (GU) tumors in a dose-escalation phase I study. We report the final data analysis of the safety, overall response rate (ORR), progression-free survival (PFS), and overall survival (OS) of the phase I patients and seven expansion cohorts. METHODS: This is an investigator-initiated, multicenter, phase I trial. CaboNivo doublet expansion cohorts included (1) mUC, (2) mRCC, and (3) adenocarcinoma of the bladder/urachal; CaboNivoIpi triplet expansion cohorts included (1) mUC, (2) mRCC, (3) penile cancer, and (4) squamous cell carcinoma of the bladder and other rare GU tumors (ClinicalTrials.gov identifier: NCT02496208). RESULTS: The study enrolled 120 patients treated with CaboNivo (n = 64) or CaboNivoIpi (n = 56), with a median follow-up of 49.2 months. In 108 evaluable patients (CaboNivo n = 59; CaboNivoIpi n = 49), the ORR was 38% (complete response rate 11%) and the median duration of response was 20 months. The ORR was 42.4% for mUC, 62.5% for mRCC (n = 16), 85.7% for squamous cell carcinoma of the bladder (n = 7), 44.4% for penile cancer (n = 9), and 50.0% for renal medullary carcinoma (n = 2). Grade ≥ 3 treatment-related adverse events occurred in 84% of CaboNivo patients and 80% of CaboNivoIpi patients. CONCLUSION: CaboNivo and CaboNivoIpi demonstrated clinical activity and safety in patients with multiple GU malignancies, especially clear cell RCC, urothelial carcinoma, and rare GU tumors such as squamous cell carcinoma of the bladder, small cell carcinoma of the bladder, adenocarcinoma of the bladder, renal medullary carcinoma, and penile cancer.

Cabozantinib plus Nivolumab Phase I Expansion Study in Patients with Metastatic Urothelial Carcinoma Refractory to Immune Checkpoint Inhibitor Therapy.

PURPOSE: This study investigated the efficacy and tolerability of cabozantinib plus nivolumab (CaboNivo) in patients with metastatic urothelial carcinoma (mUC) that progressed on checkpoint inhibition (CPI). PATIENTS AND METHODS: A phase I expansion cohort of patients with mUC who received prior CPI was treated with cabozantinib 40 mg/day and nivolumab 3 mg/kg every 2 weeks until disease progression/unacceptable toxicity. The primary goal was objective response rate (ORR) per RECIST v.1.1. Secondary objectives included progression-free survival (PFS), duration of response (DoR), overall survival (OS), safety, and tolerability. RESULTS: Twenty-nine out of 30 patients enrolled were evaluable for efficacy. Median follow-up was 22.2 months. Most patients (86.7%) received prior chemotherapy and all patients received prior CPI (median seven cycles). ORR was 16.0%, with one complete response and three partial responses (PR). Among 4 responders, 2 were primary refractory, 1 had a PR, and 1 had stable disease on prior CPI. Median DoR was 33.5 months [95% confidence interval (CI), 3.7-33.5], median PFS was 3.6 months (95% CI, 2.1-5.5), and median OS was 10.4 months (95% CI, 5.8-19.5). CaboNivo decreased immunosuppressive subsets such as regulatory T cells (Tregs) and increased potential antitumor immune subsets such as nonclassical monocytes and effector T cells. A lower percentage of monocytic myeloid-derived suppressor cells (M-MDSC) and polymorphonuclear MDSCs, lower CTLA-4 and TIM-3 expression on Tregs, and higher effector CD4+ T cells at baseline were associated with better PFS and/or OS. CONCLUSIONS: CaboNivo was clinically active, well tolerated, and favorably modulated peripheral blood immune subsets in patients with mUC refractory to CPI.

Clinical Activity of Single-Agent Cabozantinib (XL184), a Multi-receptor Tyrosine Kinase Inhibitor, in Patients with Refractory Soft-Tissue Sarcomas.

PURPOSE: Soft-tissue sarcomas (STS) are a rare, heterogeneous group of mesenchymal tumors. For decades the mainstay of treatment for advanced, unresectable STS has been palliative chemotherapy. High levels of activated MET receptor have been reported in various sarcoma cell lines, together with elevated vascular endothelial growth factor (VEGF) levels in patients with STS, suggesting that dual targeting of the VEGF and MET pathways with the multi-receptor tyrosine kinase inhibitor cabozantinib would result in clinical benefit in this population. PATIENTS AND METHODS: We performed an open-label, multi-institution, single-arm phase II trial of single-agent cabozantinib in adult patients with advanced STS and progressive disease after at least 1 standard line of systemic therapy. Patients received 60 mg oral cabozantinib once daily in 28-day cycles, and dual primary endpoints of overall response rate and 6-month progression-free survival (PFS) were assessed. Changes in several circulating biomarkers were assessed as secondary endpoints. RESULTS: Six (11.1%; 95% CI, 4.2%-22.6%) of the 54 evaluable patients enrolled experienced objective responses (all partial responses). Six-month PFS was 49.3% (95% CI, 36.2%-67.3%), with a median time on study of 4 cycles (range, 1-99). The most common grade 3/4 adverse events were hypertension (7.4%) and neutropenia (16.7%). Patients' levels of circulating hepatocyte growth factor (HGF), soluble MET, and VEGF-A generally increased after a cycle of therapy, while soluble VEGFR2 levels decreased, regardless of clinical outcome. CONCLUSIONS: Cabozantinib single-agent antitumor activity was observed in patients with selected STS histologic subtypes (alveolar soft-part sarcoma, undifferentiated pleomorphic sarcoma, extraskeletal myxoid chondrosarcoma, and leiomyosarcoma) highlighting the biomolecular diversity of STS.

Autocrine signaling by receptor tyrosine kinases in urothelial carcinoma of the bladder.

Comprehensive characterizations of bladder cancer (BCa) have established molecular phenotype classes with distinct alterations and survival trends. Extending these studies within the tyrosine kinase (TK) family to identify disease drivers could improve our use of TK inhibitors to treat specific patient groups or individuals. We examined the expression distribution of TKs as a class (n = 89) in The Cancer Genome Atlas (TCGA) muscle invasive BCa data set (n >400). Patient profiles of potentially oncogenic alterations (overexpression and/or amplification) clustered TKs into 3 groups; alterations of group 1 and 3 TKs were associated with significantly worse patient survival relative to those without alterations. Many TK pathways induce epithelial-to-mesenchymal transition (EMT), which promotes tumor invasiveness and metastasis. Overexpression and/or amplification among 9 EMT transcriptional activators occurred in 43% of TCGA cases. Co-occurring alterations of TKs and EMT transcriptional activators involved most group 1 TKs; 24% of these events were associated with significantly worse patient survival. Co-occurring alterations of receptor TKs and their cognate ligands occurred in 16% of TCGA cases and several BCa-derived cell lines. Suppression of GAS6, MST1 or CSF1, or their respective receptors (AXL, MST1R and CSF1R), in BCa cell lines was associated with decreased receptor activation, cell migration, cell proliferation and anchorage independent cell growth. These studies reveal the patterns and prevalence of potentially oncogenic TK pathway-related alterations in BCa and identify specific alterations associated with reduced BCa patient survival. Detection of these features in BCa patients could better inform TK inhibitor use and improve clinical outcomes.

Circulating Tumor Cell Subtypes and T-cell Populations as Prognostic Biomarkers to Combination Immunotherapy in Patients with Metastatic Genitourinary Cancer.

PURPOSE: Circulating tumor cells (CTC) are under investigation as a minimally invasive liquid biopsy that may improve risk stratification and treatment selection. CTCs uniquely allow for digital pathology of individual malignant cell morphology and marker expression. We compared CTC features and T-cell counts with survival endpoints in a cohort of patients with metastatic genitourinary cancer treated with combination immunotherapy. EXPERIMENTAL DESIGN: Markers evaluated included pan-CK/CD45/PD-L1/DAPI for CTCs and CD4/CD8/Ki-67/DAPI for T cells. ANOVA was used to compare CTC burden and T-cell populations across timepoints. Differences in survival and disease progression were evaluated using the maximum log-rank test. RESULTS: From December 2016 to January 2019, 183 samples from 81 patients were tested. CTCs were found in 75% of patients at baseline. CTC burden was associated with shorter overall survival (OS) at baseline (P = 0.022), but not on-therapy. Five morphologic subtypes were detected, and the presence of two specific subtypes with unique cellular features at baseline and on-therapy was associated with worse OS (0.9-2.3 vs. 28.2 months; P < 0.0001-0.013). Increasing CTC heterogeneity on-therapy had a trend toward worse OS (P = 0.045). PD-L1+ CTCs on-therapy were associated with worse OS (P < 0.01, cycle 2). Low baseline and on-therapy CD4/CD8 counts were also associated with poor OS and response category. CONCLUSIONS: Shorter survival may be associated with high CTC counts at baseline, presence of specific CTC morphologic subtypes, PD-L1+ CTCs, and low %CD4/8 T cells in patients with metastatic genitourinary cancer. A future study is warranted to validate the prognostic utility of CTC heterogeneity and detection of specific CTC morphologies.

Phase I Study of Cabozantinib and Nivolumab Alone or With Ipilimumab for Advanced or Metastatic Urothelial Carcinoma and Other Genitourinary Tumors.

PURPOSE: We assessed the safety and efficacy of cabozantinib and nivolumab (CaboNivo) and CaboNivo plus ipilimumab (CaboNivoIpi) in patients with metastatic urothelial carcinoma (mUC) and other genitourinary (GU) malignances. PATIENTS AND METHODS: Patients received escalating doses of CaboNivo or CaboNivoIpi. The primary objective was to establish a recommended phase II dose (RP2D). Secondary objectives included objective response rate (ORR), progression-free survival (PFS), duration of response (DoR), and overall survival (OS). RESULTS: Fifty-four patients were enrolled at eight dose levels with a median follow-up time of 44.6 months; data cutoff was January 20, 2020. Grade 3 or 4 treatment-related adverse events (AEs) occurred in 75% and 87% of patients treated with CaboNivo and CaboNivoIpi, respectively, and included fatigue (17% and 10%, respectively), diarrhea (4% and 7%, respectively), and hypertension (21% and 10%, respectively); grade 3 or 4 immune-related AEs included hepatitis (0% and 13%, respectively) and colitis (0% and 7%, respectively). The RP2D was cabozantinib 40 mg/d plus nivolumab 3 mg/kg for CaboNivo and cabozantinib 40 mg/d, nivolumab 3 mg/kg, and ipilimumab 1 mg/kg for CaboNivoIpi. ORR was 30.6% (95% CI, 20.0% to 47.5%) for all patients and 38.5% (95% CI, 13.9% to 68.4%) for patients with mUC. Median DoR was 21.0 months (95% CI, 5.4 to 24.1 months) for all patients and not reached for patients with mUC. Median PFS was 5.1 months (95% CI, 3.5 to 6.9 months) for all patients and 12.8 months (95% CI, 1.8 to 24.1 months) for patients with mUC. Median OS was 12.6 months (95% CI, 6.9 to 18.8 months) for all patients and 25.4 months (95% CI, 5.7 to 41.6 months) for patients with mUC. CONCLUSION: CaboNivo and CaboNivoIpi demonstrated manageable toxicities with durable responses and encouraging survival in patients with mUC and other GU tumors. Multiple phase II and III trials are ongoing for these combinations.

Cabozantinib in patients with platinum-refractory metastatic urothelial carcinoma: an open-label, single-centre, phase 2 trial.

BACKGROUND: Cabozantinib is a multikinase inhibitor of MET, VEGFR, AXL, and RET, which also has an effect on the tumour immune microenvironment by decreasing regulatory T cells and myeloid-derived suppressor cells. In this study, we examined the activity of cabozantinib in patients with metastatic platinum-refractory urothelial carcinoma. METHODS: This study was an open-label, single-arm, three-cohort phase 2 trial done at the National Cancer Institute (Bethesda, MD, USA). Eligible patients were 18 years or older, had histologically confirmed urothelial carcinoma or rare genitourinary tract histologies, Karnofsky performance scale index of 60% or higher, and documented disease progression after at least one previous line of platinum-based chemotherapy (platinum-refractory). Cohort one included patients with metastatic urothelial carcinoma with measurable disease as defined by Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. Two additional cohorts that enrolled in parallel (patients with bone-only urothelial carcinoma metastases and patients with rare histologies of the genitourinary tract) were exploratory. Patients received cabozantinib 60 mg orally once daily in 28-day cycles until disease progression or unacceptable toxicity. The primary endpoint was investigator-assessed objective response rate by RECIST in cohort one. Response was assessed in all patients who met the eligibility criteria and who received at least 8 weeks of therapy. All patients who received at least one dose of cabozantinib were included in the safety analysis. This completed study is registered with ClinicalTrials.gov, NCT01688999. FINDINGS: Between Sept 28, 2012, and Oct, 20, 2015, 68 patients were enrolled on the study (49 in cohort one, six in cohort two, and 13 in cohort three). All patients received at least one dose of cabozantinib. The median follow-up was 61·2 months (IQR 53·8-70·0) for the 57 patients evaluable for response. In the 42 evaluable patients in cohort one, there was one complete response and seven partial responses (objective response rate 19%, 95% CI 9-34). The most common grade 3-4 adverse events were fatigue (six [9%] patients), hypertension (five [7%]), proteinuria (four [6%]), and hypophosphataemia (four [6%]). There were no treatment-related deaths. INTERPRETATION: Cabozantinib has single-agent clinical activity in patients with heavily pretreated, platinum-refractory metastatic urothelial carcinoma with measurable disease and bone metastases and is generally well tolerated. Cabozantinib has innate and adaptive immunomodulatory properties providing a rationale for combining cabozantinib with immunotherapeutic strategies. FUNDING: National Cancer Institute Intramural Program and the Cancer Therapy Evaluation Program.

Serum microRNA profiles among dioxin exposed veterans with monoclonal gammopathy of undetermined significance.

Previously an increased risk for monoclonal gammopathy of undetermined significance (MGUS), a precursor of multiple myeloma (MM), was reported among Vietnam veterans exposed to Agent Orange and its contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Dysregulated expression of certain microRNAs (miRNAs) was demonstrated in MGUS and MM. Given the important role of miRNAs in cellular homeostasis, the aim of this study was to determine if there was an association between serum levels of selected miRNAs and TCDD in 47 MGUS cases identified in our previous investigation using serum specimens and exposure data archived by the Air Force Health Study (AFHS). A total of 13 miRNA levels (let-7a, let-7i, miR-16, miR-20a, miR-21, miR-34a, miR-106b, miR-146a, miR-181a, miR-192, miR-205, miR-335, and miR-361) was measured in serum stored during the 2002 AFHS follow-up and the relationship to lipid-adjusted serum TCDD levels in 1987 was determined. miR-34a showed the strongest relationship with TCDD; after age-adjustment, this positive association was more pronounced. In contrast, the other 12 miRNAs displayed absolute values of age adjusted coefficient estimates below 1.16 and non-significant p-values. The observed strong positive association between high body burdens of TCDD and miR-34a, a tumor suppressor regulated by p53, in this MGUS population warrants clarification of the TCDD-miR-34a relationship and its role in the pathogenesis of MGUS and risk for MM.

Dietary intake is associated with risk of multiple myeloma and its precursor disease.

The etiology of monoclonal gammopathy of undetermined significance (MGUS), the precursor state of multiple myeloma (MM), is mostly unknown and no studies have been conducted on the effect of diet on MGUS or progression from MGUS to MM. We aimed to explore the association between common foods and MGUS and progression to MM. Data from the population-based AGES Study (N = 5,764) were utilized. Food frequency questionnaire was used to assess dietary intake during adolescence, midlife, and late life. Serum protein electrophoresis and serum free light-chain assay was performed to identify MGUS (n = 300) and LC-MGUS cases (n = 275). We cross linked our data with the Icelandic Cancer Registry to find cases of MM in the study group. We found that intake of fruit at least three times per week during adolescence was associated with lower risk of MGUS when compared to lower fruit consumption (OR = 0.62, 95% CI 0.41-0.95). We additionally found that intake of fruit at least three times per week during the late life period was associated with decreased risk of progressing from MGUS to MM (HR = 0.34, 95% CI 0.13-0.89) when compared to lower intake. Adolescent intake of fruit may reduce risk of MGUS, whereas fruit intake after MGUS onset may reduce risk of progressing to MM. Our findings suggest that diet might alter the risk of developing MGUS and progression to MM.

Host-related immunodeficiency in the development of multiple myeloma.

Host-related immunodeficiency is known to play a role in the development of multiple myeloma (MM) from its precursor conditions (monoclonal gammopathy of undetermined significance, MGUS, smoldering multiple myeloma, SMM). In order to understand the underlying immune changes in this process, we characterized immune patterns from MGUS to SMM to MM. We further sought to identify potential novel immune biomarkers that may predict progression of SMM to MM. We characterized patterns of circulating lymphocytes in 181 patients using multiparametric flow cytometry. We found decreased B- (p = .0003), increased T- (p = .037) and unaltered NK cell proportions from MGUS to SMM to MM. To gain insights into functional variability, we further characterized immunophenotypic lymphocyte subsets, which uncovered differences in CD57 subsets. Specifically, we found that SMM patients who eventually progressed to MM showed decreased proportions of CD57-CD56 + (p = .0061) and CD57-CD16 + (p = .035) lymphocyte subsets. We thus report novel data characterizing the nature of host-related immunodeficiency in the development of MM. We show sequential changes in lymphocyte subsets from MGUS to SMM to MM. We further suggest that CD57 subsets may serve as potential markers of progression from SMM to MM. Our findings support the study of lymphocyte subsets in the search for immune biomarkers. Such markers could provide clinical guidance in managing myeloma precursor disease.

Circulating Adiponectin Levels Differ Between Patients with Multiple Myeloma and its Precursor Disease.

OBJECTIVE: An increased risk of multiple myeloma (MM) has been observed among individuals with low prediagnostic circulating levels of adiponectin, a metabolic hormone that is typically underexpressed among those with overweight or obesity. To assess whether adiponectin may influence myeloma development or progression to frank MM, circulating adiponectin levels were compared across patients with different stages of MM and its precursor, monoclonal gammopathy of undetermined significance (MGUS). METHODS: Adiponectin was measured in 213 patients with MGUS, smoldering MM, or fully developed MM. Differences in adiponectin levels across patient groups were assessed using multivariate linear regression. RESULTS: Relative to MGUS patients, adiponectin levels were statistically significantly lower among those with smoldering and fully developed MM, both overall (16%-20% decrease; P = 0.048) and among those with IgG/IgA isotypes (26%-28% decrease; P = 0.004). Among MGUS patients, adiponectin levels were significantly lower for those with the higher-risk IgM isotype compared with those who had IgG/IgA isotypes (42% decrease; P = 0.036). CONCLUSIONS: The findings of this study, the largest to investigate adiponectin levels in patients with different stages of MM and the first to evaluate associations with clinical characteristics, suggest that reduced expression of adiponectin may be associated with progression from MGUS to MM.

Enzymatic activities of circulating plasma proteasomes in newly diagnosed multiple myeloma patients treated with carfilzomib, lenalidomide and dexamethasone.

The proteasome inhibitor carfilzomib is highly effective in the treatment of multiple myeloma. It irreversibly binds the chymotrypsin-like active site in the ß5 subunit of the 20S proteasome. Despite impressive response rates when carfilzomib is used in combination with immunomodulatory agents in newly diagnosed multiple myeloma patients; no biomarker exists to accurately predict response and clinical outcomes. We prospectively assessed the activity in peripheral blood of the chymotrypsin-like (CHYM), caspase-like (CASP) and trypsin-like (TRYP) proteolytic sites in 45 newly diagnosed multiple myeloma patients treated with eight cycles of carfilzomib, lenalidomide and dexamethasone (CRd) (NCT01402284). Samples were collected per protocol and proteasome activity measured through a fluorogenic assay. Median CHYM levels after one dose of carfilzomib decreased by >70%. CHYM and CASP activity decreased throughout treatment reaching a minimum after eight cycles of treatment. Higher levels of proteasome activity associated with higher disease burden (r > 0.30; p < 0.05) and higher disease stage (0.10 < p <0.20). No association was found with the probability of achieving a complete response, minimal residual disease negativity or time to best response. Further studies evaluating proteasome activity in malignant plasma cells may help elucidate how proteasome activity can be used as a biomarker in multiple myeloma.

Baseline mutational patterns and sustained MRD negativity in patients with high-risk smoldering myeloma.

Early results of a prospective phase 2 clinical trial of carfilzomib, lenalidomide, and dexamethasone followed by lenalidomide maintenance in high-risk smoldering myeloma showed promising results that were previously published. Here, we provide novel insights into the genetic landscape of high-risk smoldering myeloma and information on sustained minimal residual disease (MRD) negativity with an expanded cohort of patients. Eighteen patients with high-risk smoldering myeloma were enrolled between 29 May 2012, and 14 January 2014. We included patients with newly diagnosed multiple myeloma enrolled in a parallel trial who received the same therapy (reference group). The overall response rate was 100%. With median potential follow-up of 43.3 months, 10 (63%) remain in MRD negativity, and the estimated 4-year progression-free and overall survival rates are 71% and 100%, respectively. Importantly, we report differences in mutational patterns in patients with high-risk smoldering myeloma and newly diagnosed multiple myeloma, reflected in a lower frequency of mutations in significant myeloma genes (6.6% vs 45%) and NFKB pathway genes (6.6% vs 25%). Treatment with carfilzomib, lenalidomide, and dexamethasone followed by lenalidomide maintenance was associated with a 100% response rate and 63% MRD negativity with a safety profile consistent with previous reports for this regimen. This study had a small numbers of participants, but there seemed to be important differences in the genetic landscape of patients with high-risk smoldering myeloma and those with newly diagnosed multiple myeloma, suggestive of a more treatment-responsive biology in early disease.

Obesity and risk of monoclonal gammopathy of undetermined significance and progression to multiple myeloma: a population-based study.

All multiple myeloma (MM) cases are preceded by the premalignant state monoclonal gammopathy of undetermined significance (MGUS). Results from previous studies show a positive association between obesity and MM; however, the association between obesity and MGUS is controversial. The aims were to determine (1) if obesity is associated with an increased risk of MGUS and light-chain MGUS (LC-MGUS) and (2) whether obesity is associated with a higher risk of progression to MM and other lymphoproliferative (LP) diseases. Data from the population-based Age, Gene/Environment Susceptibility-Reykjavik Study (N = 5764) were used. We performed serum protein electrophoresis and serum free light-chain assay on all subjects to identify MGUS and LC-MGUS cases. We included 11 different measures on current and previous obesity in our analysis. Logistic regression and Cox proportional-hazard regression were used to analyze the associations. A total of 300 (5.2%) MGUS and 275 (4.8%) LC-MGUS cases were identified. During a median follow-up of 8 years, 18 had progressed to MM and 11 to other LP diseases. We found no association between the 11 obesity markers and MGUS or LC-MGUS (odds ratios 0.81 to 1.15 for all 11 variables in both conditions). Interestingly, we found that high midlife body mass index increased risk of progression to MM and other LP diseases (hazard ratio, 2.66; 95% confidence interval, 1.17-6.05). To conclude, obesity was not associated with MGUS. However, we found overweight/obesity to be a risk factor for progression from MGUS to MM and other LP diseases, suggesting that obesity plays a role in the transformation of MGUS to MM.

Bone disease in monoclonal gammopathy of undetermined significance: results from a screened population-based study.

Previous studies have shown that individuals with monoclonal gammopathy of undetermined significance (MGUS) have an increased risk of fractures, although the underlying mechanisms remain unknown. Our aim was to analyze bone mineral density (BMD), bone volume, and risk of fractures among individuals with MGUS. We performed a screening using the Age, Gene/Environment Susceptibility (AGES)-Reykjavik Study cohort, consisting of 5764 elderly individuals, identifying 300 individuals with MGUS, and 275 with light-chain MGUS. Quantitative computerized tomography was performed in the lumbar spine and hip to evaluate BMD and bone geometry. Analysis of variance and the Tukey honest significance test were used to compare the groups. Hospital records were used to record fractures, with a mean follow-up of 6.9 years. Cox proportional hazard was used to compare fracture risk. No difference was found in BMD between subjects with MGUS and others in the spine (P = .34) or in total hip (P = .30). Individuals with MGUS had a significant increase in bone volume compared with others in the spine (P < .001) and total hip (P < .001). Overall, the risk of fractures was not significantly increased in individuals with MGUS (hazard ratio [HR], 1.19; 95% confidence interval [CI], 0.94-1.50). Men with MGUS had a significantly increased fracture risk, compared with other men (HR, 1.46; 95% CI, 1.03-2.08). Our results show that although individuals with MGUS do not have decreased BMD, bone volume is increased, and MGUS men have a 50% increased fracture risk. These results indicate that bone disease and fractures in MGUS differ from processes known from osteoporosis.

Monoclonal gammopathy-associated pure red cell aplasia.

Pure red cell aplasia (PRCA) is a rare disorder characterized by inhibition of erythroid precursors in the bone marrow and normochromic, normocytic anaemia with reticulocytopenia. Among 51 PRCA patients, we identified 12 (24%) patients having monoclonal gammopathy, monoclonal gammopathy of undetermined significance or smouldering multiple myeloma, with presence of monoclonal protein or abnormal serum free light chains and atypical bone marrow features of clonal plasmacytosis, hypercellularity and fibrosis. Thus far, three patients treated with anti-myeloma based therapeutics have responded with reticulocyte recovery and clinical transfusion independence, suggesting plasma cells play a key role in the pathogenesis of this specific monoclonal gammopathy-associated PRCA.

Aberrant Levels of miRNAs in Bone Marrow Microenvironment and Peripheral Blood of Myeloma Patients and Disease Progression.

The bone marrow (BM) microenvironment of multiple myeloma (MM) is reported to play a role in the biology of disease. In this study, we found that the extracellular BM microenvironment in MM contains a unique miRNA signature detectable by miRNA microarray and quantitative real-time PCR, which is partially represented in the peripheral blood. Eleven miRNAs were significantly decreased in both BM and serum of MM patients in comparison with controls. Evaluation of these miRNAs in plasma of a separate cohort of MM patients and controls confirmed significantly aberrant levels of let-7a, let-7b, let-7i, miR-15b, miR-16, and miR-20a in both serum and plasma. We then studied the myeloma precursor diseases and found that a subset of the MM miRNAs exhibited aberrant expression in monoclonal gammopathy of undetermined significance and smoldering myeloma. miRNA analysis of enriched CD138(+) plasma cells from MM and monoclonal gammopathy of undetermined significance found that most of the validated MM BM signature miRNAs were significantly decreased in MM plasma cells. Gene expression profiling indicated that multiple targets of the decreased miRNAs found increased expression in MM plasma cells, including ATF2, HRAS, HDAC4, TGFB1, TGFBR1, and mitogen-activated protein kinases. The findings suggest that these miRNAs are detectable in aberrant levels in the peripheral blood of patients with plasma cell proliferation and may play a role in aberrant plasma cell proliferation and disease progression.

Agent Orange Exposure and Monoclonal Gammopathy of Undetermined Significance: An Operation Ranch Hand Veteran Cohort Study.

IMPORTANCE: Multiple myeloma has been classified as exhibiting "limited or suggestive evidence" of an association with exposure to herbicides in Vietnam War veterans. Occupational studies have shown that other pesticides (ie, insecticides, herbicides, fungicides) are associated with excess risk of multiple myeloma and its precursor state, monoclonal gammopathy of undetermined significance (MGUS); however, to our knowledge, no studies have uncovered such an association in Vietnam War veterans. OBJECTIVE: To examine the relationship between MGUS and exposure to Agent Orange, including its contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), in Vietnam War veterans. DESIGN, SETTING, AND PARTICIPANTS: This was a prospective cohort study conducted in 2013 to 2014, testing for MGUS in serum specimens collected and stored in 2002 by the Air Force Health Study (AFHS). The relevant exposure data collected by the AFHS was also used. We tested all specimens in 2013 without knowledge of the exposure status. The AFHS included former US Air Force personnel who participated in Operation Ranch Hand (Ranch Hand veterans) and other US Air Force personnel who had similar duties in Southeast Asia during the same time period (1962 to 1971) but were not involved in herbicide spray missions (comparison veterans). Agent Orange was used by the US Air Force personnel who conducted aerial spray missions of herbicides (Operation Ranch Hand) in Vietnam from 1962 to 1971. We included 479 Ranch Hand veterans and 479 comparison veterans who participated in the 2002 follow-up examination of AFHS. EXPOSURES: Agent Orange and TCDD. Serum TCDD levels were measured in 1987, 1992, 1997, and 2002. MAIN OUTCOMES AND MEASURES: Risk of MGUS measured by prevalence, odds ratios (ORs), and 95% CIs. RESULTS: The 479 Ranch Hand veterans and 479 comparison veterans had similar demographic and lifestyle characteristics and medical histories. The crude prevalence of overall MGUS was 7.1% (34 of 479) in Ranch Hand veterans and 3.1% (15 of 479) in comparison veterans. This translated into a 2.4-fold increased risk for MGUS in Ranch Hand veterans than comparison veterans after adjusting for age, race, BMI in 2002, and the change in BMI between 2002 and the time of blood draw for TCDD measurement (adjusted OR, 2.37; 95% CI, 1.27-4.44; P=.007). CONCLUSIONS AND RELEVANCE: Operation Ranch Hand veterans have a significantly increased risk of MGUS, supporting an association between Agent Orange exposure and multiple myeloma.

Treatment With Carfilzomib-Lenalidomide-Dexamethasone With Lenalidomide Extension in Patients With Smoldering or Newly Diagnosed Multiple Myeloma.

IMPORTANCE: Carfilzomib-lenalidomide-dexamethasone therapy yields deep responses in patients with newly diagnosed multiple myeloma (NDMM). It is important to gain an understanding of this combination's tolerability and impact on minimal residual disease (MRD) negativity because this end point has been associated with improved survival. OBJECTIVE: To assess the safety and efficacy of carfilzomib-lenalidomide-dexamethasone therapy in NDMM and high-risk smoldering multiple myeloma (SMM). DESIGN, SETTING, AND PARTICIPANTS: Clinical and correlative pilot study at the National Institutes of Health Clinical Center. Patients with NDMM or high-risk SMM were enrolled between July 11, 2011, and October 9, 2013. Median follow-up was 17.3 (NDMM) and 15.9 months (SMM). INTERVENTIONS: Eight 28-day cycles were composed of carfilzomib 20/36 mg/m2 on days 1, 2, 8, 9, 15, and 16; lenalidomide 25 mg on days 1 through 21; and dexamethasone 20/10 mg (cycles 1-4/5-8) on days 1, 2, 8, 9, 15, 16, 22, and 23. Patients who achieved at least stable disease subsequently received 24 cycles of lenalidomide extended dosing. MAIN OUTCOMES AND MEASURES: Primary end points were neuropathy of grade 3 or greater (NDMM) and at least very good partial response rates (SMM). Minimal residual disease was also assessed. RESULTS: Of 45 patients with NDMM, none had neuropathy of grade 3 or greater. Of 12 patients with high-risk SMM, the most common of any-grade adverse events were lymphopenia (12 [100%]) and gastrointestinal disorders (11 [92%]). All patients with SMM achieved at least a very good partial response during the study period. Among the 28 patients with NDMM and the 12 with SMM achieving at least a near-complete response, MRD negativity was found in 28 of 28 (100% [95% CI, 88%-100%]), 11 of 12 (92% [95% CI, 62%-100%]) (multiparametric flow cytometry), 14 of 21 (67% [95% CI, 43%-85%]), and 9 of 12 (75% [95% CI, 43%-94%]) (next-generation sequencing), respectively. In patients with NDMM, 12-month progression-free survival for MRD-negative vs MRD-positive status by flow cytometry and next-generation sequencing was 100% vs 79% (95% CI, 47%-94%; P < .001) and 100% vs 95% (95% CI, 75%-99%; P = .02), respectively. CONCLUSIONS AND RELEVANCE: Carfilzomib-lenalidomide-dexamethasone therapy is tolerable and demonstrates high rates of MRD negativity in NDMM, translating into longer progression-free survival in patients achieving MRD negativity. Carfilzomib-lenalidomide-dexamethasone therapy also demonstrates efficacy in high-risk SMM.