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31.
In low and middle-income countries mammographic breast cancer screening is prohibitively expensive and a cheaper alternative option is to use ultrasound as the primary screening test. In 2009, China launched a breast cancer screening programme for rural women aged 35–64 years with clinical breast examination coupled with ultrasound as the primary tool. Our study aimed to analyse the cost-effectiveness of breast screening compared to no screening among Chinese rural women. We developed a Markov model to estimate the lifetime costs and effects for rural women aged 35 years from a societal perspective. Asymptomatic women in the intervention arm were screened every 3 years before age 64 years. Breast cancer in the non-screening arm can only be diagnosed on presentation of symptoms. Parameter uncertainty was explored using one-way and probabilistic sensitivity analyses. Compared to no screening, breast cancer screening cost $186.7 more and led to a loss of 0.20 quality-adjusted life years (QALYs). Breast screening was more expensive and did harm to health among rural women with an incremental cost-effectiveness ratio (ICER) of $-916/QALY. The sensitivity analysis identified utility loss from false positives as the factor that most influenced the results, but this did not affect the conclusions. In a rural setting with such low breast cancer incidence, screening for asymptomatic disease is not cost-effective with current screening tools. Priority should be given to ensure that symptomatic women have proper access to diagnosis and treatment at an early stage as this will lead to mortality reductions without the usual screening harms.  相似文献   
32.
Background: Palbociclib is a selective cyclin-dependent kinase (CDK) 4/6 inhibitor used in combination with aromatase inhibitors or fulvestrant for patients with hormone receptor-positive (HR+) human epidermal growth factor receptor 2 (HER2)-negative advanced/metastatic breast cancer (ABC/MBC). Palbociclib was the first CDK 4/6 inhibitor approved for HR+/HER2− ABC/MBC treatment in Canada in combination with letrozole (P+L) as an initial endocrine-based therapy (approved March 2016), or with fulvestrant (P+F) following disease progression after prior endocrine therapy (approved May 2017). The Ibrance Real World Insights (IRIS) study (NCT03159195) collected real-world outcomes data for palbociclib-treated patients in several countries, including Canada. Methods: This retrospective chart review included women with HR+/HER2− ABC/MBC receiving P+L or P+F in Canada. Physicians reviewed medical records for up to 14 patients, abstracting demographic and clinical characteristics, treatment patterns, and clinical outcomes. Progression-free rates (PFRs) and survival rates (SRs) at 6, 12, 18, and 24 months were estimated via Kaplan–Meier analysis. Results: Thirty-three physicians examined medical records for 247 patients (P+L, n = 214; P+F, n = 33). Median follow-up was 8.8 months for P+L and 7.0 months for P+F. Most patients were initiated on palbociclib 125 mg/d (P+L, 90.2%; P+F, 84.8%). Doses were reduced in 16.6% of P+L and 14.3% of P+F patients initiating palbociclib at 125 mg/d. The PFR for P+L was 90.3% at 12 months and 78.2% at 18 months; corresponding SRs were 95.6% and 93.0%. For P+F, 6-month PFR was 91.0%; 12-month SR was 100.0%. Conclusions: Dose reduction rates were low and PFR and SR were high in this Canadian real-world assessment of P+L and P+F treatments, suggesting that palbociclib combinations are well tolerated and effective.  相似文献   
33.
目的:研究乳腺癌细胞中转录调节因子c-Myb的表达对肺转移的影响及其分子机制。方法:构建c-Myb高表达的4T1乳腺癌细胞株,种植小鼠构建乳腺癌动物模型,检测实验动物肺转移情况,通过荷瘤抑制试验检测肺转移抑制效果。提取组织进行荧光PCR检测相关炎症因子的表达。利用Medisapiens数据库的生物信息学资源,对c-Myb和Ccl2的表达与乳腺癌患者的预后进行分析。结果:高表达c-Myb的荷瘤小鼠肺部转移灶明显减少,其中炎症相关因子表达受限。由数据库分析得出,c-Myb高表达患者生存期得以延长。结论:乳腺癌中c-Myb的表达能够通过炎症因子Ccl2抑制肺转移从而延长患者生存期。  相似文献   
34.
35.
G protein-coupled estrogen receptor-1 (GPER), a member of the G protein-coupled receptor (GPCR) superfamily, mediates estrogen-induced proliferation of normal and malignant breast epithelial cells. However, its role in breast cancer stem cells (BCSCs) remains unclear. Here we showed greater expression of GPER in BCSCs than non-BCSCs of three patient-derived xenografts of ER/PR+ breast cancers. GPER silencing reduced stemness features of BCSCs as reflected by reduced mammosphere forming capacity in vitro, and tumor growth in vivo with decreased BCSC populations. Comparative phosphoproteomics revealed greater GPER-mediated PKA/BAD signaling in BCSCs. Activation of GPER by its ligands, including tamoxifen (TMX), induced phosphorylation of PKA and BAD-Ser118 to sustain BCSC characteristics. Transfection with a dominant-negative mutant BAD (Ser118Ala) led to reduced cell survival. Taken together, GPER and its downstream signaling play a key role in maintaining the stemness of BCSCs, suggesting that GPER is a potential therapeutic target for eradicating BCSCs.  相似文献   
36.
HER2-positive breast cancer is an aggressive subtype identified in the 1980s. The development of therapies targeting the HER2 has improved outcomes. The current standard of care, established in 2012 is dual blockade with trastuzumab + pertuzumab as first-line followed by TDM-1 as second-line. Several suboptimal choices are available in third-line or more. In 2019 the presentation of several trials evaluating new drugs and regimens in third-line has re-opened questions about sequencing, treatment of triple positive disease and treatment choice after exposure to TDM-1. These include tucatinib, neratinib and trastuzumab-deruxtecan. Other agents – including other antibody drug conjugates and bispecific antibodies as well as combinations - will lead to further changes in coming years. Additionally, should the numerous putative biomarkers thus identified ever come into use at the clinic, choice of treatment and response evaluation may be substantially changed.  相似文献   
37.
目的:探讨乳腺弥漫大B细胞淋巴瘤(DLBCL)患者的临床特征及预后。方法:回顾性分析2014年5月起至2018年12月我院收治的18例乳腺DLBCL患者的临床特点及预后。结果:在18例患者中,17例为女性,中位年龄为57岁,病变主要累及右侧乳腺(11/18,61.1%)。将其分为原发性乳腺DLBCL(PB-DLBCL)和继发性乳腺DLBCL(SB-DLBCL)两大类。11例(57.6%)PB-DLBCL与7例(42.4%)SB-DLBCL相比,其具有Ann Arbor分期多为Ⅰ-Ⅱ期(P<0.01)、B症状少(P=0.013)、相对更高的白细胞计数(P=0.041)、骨髓未累及(P=0.043)、完全缓解(CR)率高(P=0.049)等特点。生存分析发现PB-DLBCL患者5年总生存期(OS)显著长于SB-DLBCL患者(P=0.013)。本研究以非生发中心B细胞型(non-GCB)居多,生发中心型(GCB)与non-GCB型之间OS无显著差异(P=0.885)。所有获得CR患者的生存期均显著延长(P=0.008)。结论:乳腺DLBCL多见于中年女性,以右侧乳腺肿块为主要临床表现,分子分型多为non-GCB型。与SB-DLBCL患者相比,PB-DLBCL患者具有Ann Arbor分期早、B症状少、相对更高的白细胞计数、骨髓未累及、CR率高等特点,并且生存期显著延长。无论是PB-DLBCL和SB-DLBCL,还是GCB型和non-GCB型,获得CR提示预后良好。  相似文献   
38.
Background: Up to half of the heritable mutations in breast cancer (BC) are attributed to BRCA1 and BRCA2 genes. The mutation prevalence is variable based on ethnicity and may be influenced by founder mutations. The aim of this pilot study is to determine for the first time, the prevalence of BRCA1 5382insC founder mutation in a cohort of Egyptian familial breast cancer patients (FBC). Methods: Female patients were selected to have familial type of breast cancer. Twenty healthy females were included as a control group. Peripheral blood samples were withdrawn from all studied females and were analyzed for BRCA1 5382insC founder mutation detection using pyrosequencing technique. Results: Eighty Egyptian FBC females were eligible to be enrolled in the study with a mean age of 48.31 ± 10.97years.We found a BRCA1 5382insC mutation carrier frequency of 5% of total studied FBC patients (4 out of 80 patients) with 95% confidence interval (1.61-12.99). There was a high statistical significant difference between carriers and non-carriers concerning the number of affected family members by BC, (p=0.001).  Conclusion: BRCA1 5382insC founder mutation is not uncommon among Egyptian FBC females. The carrier frequency is comparable to that reported worldwide; however it is lower than those from previous Egyptian studies using different molecular techniques. The strong association between the mutation and the number of affected family members suggest wider screening of the mutation among high risk families using the reliable pyrosequencing technique.  相似文献   
39.
目的:利用整合生物信息学手段分析EZH2(enhancer of zeste 2 polycomb repressive complex 2 subunit)基因在乳腺癌中的表达及其临床意义。方法:在肿瘤基因组计划数据库(The Cancer Genome Atlas,TCGA)中下载乳腺癌与正常乳腺组织的基因表达谱数据,进一步利用Ualcan数据库和人类蛋白质图谱(The Human Protein Atlas)数据库数据分析EZH2基因在乳腺癌中的mRNA及蛋白表达水平。利用Ualcan数据库分析EZH2基因的甲基化水平并筛选其共表达基因;对EZH2及其共表达基因进行GO(Gene Ontology)富集分析和KEGG通路分析以明确EZH2的共表达基因参与的生物学过程和相关通路;使用Kaplan-Meier生存分析法分析乳腺癌患者的总生存期、无病生存期、无远处转移生存期及后进展生存期与EZH2基因表达水平的关系并绘制生存曲线。结果:与正常乳腺组织相比,EZH2在乳腺癌组织中的mRNA及蛋白表达量明显升高。而EZH2的甲基化程度在乳腺癌组织与正常乳腺组织中则差异不明显。同时,EZH2的表达水平与年龄、乳腺癌分期及乳腺癌分子分型等因素密切相关。EZH2及其共表达基因主要参与了核碱基的调节、细胞周期调控、染色体分离、DNA复制、DNA修复等生物学过程,并参与了细胞周期、DNA 复制、M/G1期转化、M期、有丝分裂前中期、ATM通路等生物学通路。此外,EZH2基因表达水平高的乳腺癌患者的总生存期、无病生存期、无远处转移生存期及后进展生存期均明显低于EZH2基因低表达的患者。结论:EZH2在乳腺癌组织中高表达并且与患者不良预后密切相关。同时,EZH2的表达水平与乳腺癌的发生、发展密切相关。EZH2在乳腺癌诊断、靶向治疗及预后分析中具有重要的临床意义。  相似文献   
40.
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