Citations

ABSTRACTGenes that alter disease risk only in combination with certain environmental exposures may not be detected in genetic association analysis. By using methods accounting for gene‐environment (G × E) interaction, we aimed to identify novel genetic loci associated with breast cancer risk. Up to 34,475 cases and 34,786 controls of European ancestry from up to 23 studies in the Breast Cancer Association Consortium were included. Overall, 71,527 single nucleotide polymorphisms (SNPs), enriched for association with breast cancer, were tested for interaction with 10 environmental risk factors using three recently proposed hybrid methods and a joint test of association and interaction. Analyses were adjusted for age, study, population stratification, and confounding factors as applicable. Three SNPs in two independent loci showed statistically significant association: SNPs rs10483028 and rs2242714 in perfect linkage disequilibrium on chromosome 21 and rs12197388 in ARID1B on chromosome 6. While rs12197388 was identified using the joint test with parity and with age at menarche (P‐values = 3 × 10−07), the variants on chromosome 21 q22.12, which showed interaction with adult body mass index (BMI) in 8,891 postmenopausal women, were identified by all methods applied. SNP rs10483028 was associated with breast cancer in women with a BMI below 25 kg/m2 (OR = 1.26, 95% CI 1.15–1.38) but not in women with a BMI of 30 kg/m2 or higher (OR = 0.89, 95% CI 0.72–1.11, P for interaction = 3.2 × 10−05). Our findings confirm comparable power of the recent methods for detecting G × E interaction and the utility of using G × E interaction analyses to identify new susceptibility loci.

Abstract Part of the substantial unexplained familial aggregation of breast cancer may be due to interactions between common variants, but few studies have had adequate statistical power to detect interactions of realistic magnitude. We aimed to assess all two-way interactions in breast cancer susceptibility between 70 917 single nucleotide polymorphisms (SNPs) selected primarily based on prior evidence of a marginal effect. Thirty-eight international studies contributed data for 46 450 breast cancer cases and 42 461 controls of European origin as part of a multi-consortium project (COGS). First, SNPs were preselected based on evidence (P < 0.01) of a per-allele main effect, and all two-way combinations of those were evaluated by a per-allele (1 d.f.) test for interaction using logistic regression. Second, all 2.5 billion possible two-SNP combinations were evaluated using Boolean operation-based screening and testing, and SNP pairs with the strongest evidence of interaction (P < 10−4) were selected for more careful assessment by logistic regression. Under the first approach, 3277 SNPs were preselected, but an evaluation of all possible two-SNP combinations (1 d.f.) identified no interactions at P < 10−8. Results from the second analytic approach were consistent with those from the first (P > 10−10). In summary, we observed little evidence of two-way SNP interactions in breast cancer susceptibility, despite the large number of SNPs with potential marginal effects considered and the very large sample size. This finding may have important implications for risk prediction, simplifying the modelling required. Further comprehensive, large-scale genome-wide interaction studies may identify novel interacting loci if the inherent logistic and computational challenges can be overcome.

Objective Diffuse alveolar hemorrhage (DAH) is an uncommon complication of primary antiphospholipid syndrome (APS). We aimed to describe the clinical characteristics, treatment, and outcomes of primary APS–associated DAH in a single center. Methods We conducted a retrospective review of all adults with primary APS–associated DAH evaluated at Mayo Clinic over a 15‐year period. DAH was defined as bilateral pulmonary infiltrates and bronchoalveolar lavage (BAL) fluid documenting progressively bloody returns and/or the presence of >20% hemosiderin‐laden macrophages. Patients with other causes of DAH were excluded. Results Eighteen patients were identified (median age 43 years). Capillaritis was present in surgical lung biopsy samples of 3 patients. BAL differential cell counts revealed predominantly neutrophils. All patients were treated initially with glucocorticoids. Cyclophosphamide (CYC) was used in 8 patients; complete remission was achieved in 3 patients treated with CYC alone and in 1 patient receiving combination therapy with rituximab (RTX). RTX was used in 9 patients; 2 patients achieved remission with RTX alone, whereas 3 patients required combination therapy with CYC or mycophenolate mofetil (MMF). No patient achieved complete remission while receiving single therapy with MMF, azathioprine, or plasma exchange. Intravenous gamma globulin therapy was administered in 5 patients; no patient achieved control of the disease. Six patients died, all because of complications related to uncontrolled DAH or its therapy. Conclusion We present the largest case series of primary APS–associated DAH reported in the literature. DAH carries a very poor prognosis and therapeutic options are limited. Immunosuppression with either CYC or RTX is associated with the highest likelihood of remission induction and should be considered early.

ObjectiveTo evaluate the reasons that complete remission is not achieved or maintained with original treatment in some patients with antineutrophil cytoplasmic antibody (ANCA)–associated vasculitis (AAV) treated with rituximab (RTX) or with cyclophosphamide/azathioprine (CYC/AZA).MethodsThe Rituximab in AAV trial was a randomized, double‐blind, placebo‐controlled trial comparing the rate of remission induction among patients treated with RTX (n = 99) and patients treated with CYC followed by AZA (n = 98). Glucocorticoids were tapered over a period of 5 months. The primary outcome measure was lack of disease activity without glucocorticoid treatment at 6 months. To determine the most important reason for failure to achieve the primary outcome, 7 hierarchical categories of reasons were defined retrospectively (uncontrolled disease, adverse event leading to therapy discontinuation, severe flare, limited flare, Birmingham Vasculitis Activity Score for Wegener's Granulomatosis >0, prednisone treatment at any dosage, and other).ResultsAlthough remission (lack of disease activity) was achieved in 170 of the 197 patients (86%) in the first 6 months, the primary outcome measure was not achieved in 42%. There were 3 deaths. Twenty‐four percent of the patients failed to achieve the primary end point due to active disease: 10 (5%) experienced uncontrolled disease in the first month and 37 (19%) experienced flares after initial improvement. In the majority of such patients, treatment with blinded crossover or according to best medical judgment led to disease control. Ninety‐one percent of patients who had uncontrolled disease or experienced a severe flare had proteinase 3 (PR3)–ANCA. When patients with uncontrolled disease were excluded from analysis, those who were PR3‐ANCA positive were found to experience fewer flares when treated with RTX compared to CYC/AZA (8 of 59 [14%] versus 20 of 62 [32%]; P = 0.02). Neither ANCA titers nor B cell counts predicted disease flare.ConclusionCurrent treatment regimens are largely successful in controlling AAV, but in approximately one‐fourth of patients, active disease persists or recurs in the first 6 months despite treatment. PR3‐ANCA positivity is a risk factor for recurrence or persistence of severe disease. ANCA titers and B cell detectability are poor predictors of both disease relapse and disease quiescence in the first 6 months.

Granulomatosis with polyangiitis (Wegener’s) (GPA) may mimic IgG4-related disease (IgG4-RD) on histologic examination of some biopsies, especially those from head and neck sites. IgG4 immunostain is often performed in this context for differential diagnosis with IgG4-RD. However, the prevalence of IgG4+ cells in GPA has not been explored. We examined the IgG4+ cells in 26 cases confirmed as GPA by a thorough clinical and pathologic assessment. Twenty-six biopsies consisted of 14 sinonasal/oral cavity/nasopharynx, 7 orbit/periorbital, 3 lung/pleura, 1 iliac fossa/kidney, and 1 dura specimens. Eight of 26 (31%) biopsies revealed increased IgG4+ cells (>30/HPF and >40% in IgG4+/IgG+ ratio). The IgG4+ cells and IgG4+/IgG+ ratio ranged 37–137/hpf and 44–83%, respectively. Eight biopsies with increased IgG4+ cells were from sinonasal(n=4)or orbital/periorbital(n=4)sites. In conclusion, increased IgG4+ cells are not uncommonly seen in sinonasal or orbital/periorbital biopsies of GPA, which could pose as a diagnostic pitfall.

Background and Purpose— Telemedicine techniques can be used to address the rural–metropolitan disparity in acute stroke care. The Stroke Team Remote Evaluation Using a Digital Observation Camera (STRokE DOC) trial reported more accurate decision making for telemedicine consultations compared with telephone-only and that the California-based research network facilitated a high rate of thrombolysis use, improved data collection, low risk of complications, low technical complications, and favorable assessment times. The main objective of the STRokE DOC Arizona TIME (The Initial Mayo Clinic Experience) trial was to determine the feasibility of establishing, de novo, a single-hub, multirural spoke hospital telestroke research network across a large geographical area in Arizona by replicating the STRokE DOC protocol. Methods— Methods included prospective, single-hub, 2-spoke, randomized, blinded, controlled trial of a 2-way, site-independent, audiovisual telemedicine system designed for remote examination of adult patients with acute stroke versus telephone consultation to assess eligibility for treatment with intravenous thrombolysis. The primary outcome measure was whether the decision to give thrombolysis was correct. Secondary outcomes were rate of thrombolytic use, 90-day functional outcomes, incidence of intracerebral hemorrhages, and technical observations. Results— From December 2007 to October 2008, 54 patients were assessed, 27 of whom were randomized to each arm. Mean National Institutes of Health Stroke Scale score at presentation was 7.3 (SD 6.2) points. No consultations were aborted; however, technical problems (74%) were prevalent in the telemedicine arm. Overall, the correct treatment decision was established in 87% of the consultations. Both modalities, telephone (89% correct) and telemedicine (85% correct), performed well. Intravenous thrombolytic treatment was used in 30% of the telemedicine and telephone consultations. Good functional outcomes at 90 days were not significantly different. There were no statistically significant differences in mortality (4% in telemedicine and 11% in telephone) or rates of intracerebral hemorrhage (4% in telemedicine and 0% in telephone). Conclusions— It is feasible to extend the original STRokE DOC trial protocol to a new state and establish an operational single-hub, multispoke rural hospital telestroke research network in Arizona. The trial was not designed to have sufficient power to detect a difference between the 2 consultative modes: telemedicine and telephone-only. Whether by telemedicine or telephone consultative modalities, there were appropriate treatment decisions, high rates of thrombolysis use, improved data collection, low rates of intracerebral hemorrhage, and equally favorable time requirements. The learning curve was steep for the hub and spoke personnel of the new telestroke network, as reflected by frequent technical problems. Overall, the results support the effectiveness of highly organized and structured stroke telemedicine networks for extending expert stroke care into rural remote communities lacking sufficient neurological expertise.

We executed a genome-wide association scan for age-related macular degeneration (AMD) in 2,157 cases and 1,150 controls. Our results validate AMD susceptibility loci near CFH ( P < 10 −75 ), ARMS2 ( P < 10 −59 ), C2/CFB ( P < 10 −20 ), C3 ( P < 10 −9 ), and CFI ( P < 10 −6 ). We compared our top findings with the Tufts/Massachusetts General Hospital genome-wide association study of advanced AMD (821 cases, 1,709 controls) and genotyped 30 promising markers in additional individuals (up to 7,749 cases and 4,625 controls). With these data, we identified a susceptibility locus near TIMP3 (overall P = 1.1 × 10 −11 ), a metalloproteinase involved in degradation of the extracellular matrix and previously implicated in early-onset maculopathy. In addition, our data revealed strong association signals with alleles at two loci ( LIPC , P = 1.3 × 10 −7 ; CETP , P = 7.4 × 10 −7 ) that were previously associated with high-density lipoprotein cholesterol (HDL-c) levels in blood. Consistent with the hypothesis that HDL metabolism is associated with AMD pathogenesis, we also observed association with AMD of HDL-c—associated alleles near LPL ( P = 3.0 × 10 −3 ) and ABCA1 ( P = 5.6 × 10 −4 ). Multilocus analysis including all susceptibility loci showed that 329 of 331 individuals (99%) with the highest-risk genotypes were cases, and 85% of these had advanced AMD. Our studies extend the catalog of AMD associated loci, help identify individuals at high risk of disease, and provide clues about underlying cellular pathways that should eventually lead to new therapies.

Abstract Rationale Standard therapy for Wegener's granulomatosis is fraught with substantial toxicity and not always effective. B lymphocytes have been implicated in the pathogenesis of Wegener's granulomatosis. Their depletion has been proposed as salvage therapy for refractory disease. Earlier encouraging reports are confounded by concomitant immunosuppressive medications and include only limited available biomarker data. Objectives To evaluate the efficacy and safety of rituximab for remission induction in refractory Wegener's granulomatosis. Methods A prospective open-label pilot trial was conducted with 10 patients monitored for 1 yr. Included were patients with active severe antineutrophil cytoplasmic antibody (ANCA)–associated vasculitis, ANCA positivity, and resistance to (or intolerance of) cyclophosphamide. The remission induction regimen consisted of oral prednisone (1 mg/kg/d) and four weekly infusions of rituximab (375 mg/m2). Prednisone was tapered and discontinued over 5 mo. Failure to achieve remission, a clinical flare in the absence of B lymphocytes, and inability to complete the glucocorticoid taper were considered treatment failures. Main Results Three women and seven men (median age, 57 yr; range, 25–72 yr) were enrolled. All had ANCA reacting with proteinase-3. The median activity score at enrollment was 6 (range, 5–10). All patients tolerated rituximab well, achieved swift B-lymphocyte depletion and complete clinical remission (activity score, 0) by 3 mo, and were tapered off glucocorticoids by 6 mo. Five patients were retreated with rituximab alone for recurring/rising ANCA titers according to protocol. One patient experienced a clinical flare after B lymphocyte reconstitution. Conclusion In this cohort, rituximab was a well-tolerated and effective remission induction agent for severe refractory Wegener's granulomatosis.