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Tamoxifen prevents recurrence of breast cancer and is suggested for preventive risk-reducing therapy. Tamoxifen reduces mammographic density, a proxy for therapy response, but little is known about its effects in remodelling normal breast tissue. Our study, a substudy within the double-blinded dose-determination trial KARISMA, investigated tamoxifen-specific changes in breast tissue composition and histological markers in healthy women. We included 83 healthy women randomised to 6 months daily intake of 20, 10, 5, 2.5, 1 mg of tamoxifen or placebo. The groups were combined to “no dose” (0-1 mg), “low-dose” (2.5-5 mg) or “high-dose” (10-20 mg) of tamoxifen. Ultrasound-guided biopsies were collected before and after tamoxifen exposure. In each biopsy, epithelial, stromal and adipose tissues was quantified, and expression of epithelial and stromal Ki67, oestrogen receptor (ER) and progesterone receptor (PR) analysed. Mammographic density using STRATUS was measured at baseline and end-of-tamoxifen-exposure. We found that different doses of tamoxifen reduced mammographic density and glandular-epithelial area in premenopausal women and associated with reduced epithelium and increased adipose tissue. High-dose tamoxifen also decreased epithelial ER and PR expressions in premenopausal women. Premenopausal women with the greatest reduction in proliferation also had the greatest epithelial reduction. In postmenopausal women, high-dose tamoxifen decreased the epithelial area with no measurable density decrease. Tamoxifen at both low and high doses influences breast tissue composition and expression of histological markers in the normal breast. Our findings connect epithelial proliferation with tissue remodelling in premenopausal women and provide novel insights to understanding biological mechanisms of primary prevention with tamoxifen.  相似文献   
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Chronic Hepatitis B is a highly prevalent disease worldwide and is estimated to cause more than 800000 annual deaths from complications such as cirrhosis and hepatocellular carcinoma (HCC). Although universal hepatitis B vaccination programs may have reduced the incidence and prevalence of chronic hepatitis B and related HCC, the disease still imposes a significant healthcare burden in many endemic regions such as Africa and the Asia-Pacific region. This is especially concerning given the global underdiagnosis of hepatitis B and the limited availability of vaccination, screening, and treatment in low-resource regions. Demographics including male gender, older age, ethnicity, and geographic location as well as low socioeconomic status are more heavily impacted by chronic hepatitis B and related HCC. Methods to mitigate this impact include increasing screening in high-risk groups according to national guidelines, increasing awareness and health literacy in vulnerable populations, and developing more robust vaccination programs in under-served regions.  相似文献   
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目的探讨肺癌患者化疗后的癌胚抗原(CEA)、神经元特异性烯醇化酶(NSE)和鳞状上皮细胞癌抗原(SCC-Ag)表达变化。方法选取2017年5月至2020年2月间南京市六合区人民医院收治的100例肺癌患者,将这些患者作为肺癌组,另随机选取同期100例健康体检人员作为健康组。统计分析两组人员化疗前的血清NSE、CEA、SCC-Ag表达水平、肺癌组化疗成功患者化疗前后的血清NSE、CEA、SCC-Ag表达水平、肺癌组化疗失败患者化疗前后的血清NSE、CEA、SCC-Ag表达水平。结果肺癌组患者化疗前的血清NSE、CEA和SCC-Ag表达水平均高于健康组,差异均有统计学意义(均P <0.05)。肺癌组化疗成功患者化疗后的血清NSE、CEA和SCC-Ag表达水平均低于化疗前,均高于健康组,差异均有统计学意义(P <0.05)。肺癌组化疗失败患者化疗后的血清NSE、CEA、SCC-Ag表达水平均高于化疗前,均高于健康组,差异均有统计学意义(P <0.05)。结论对肺癌患者的NSE、CEA、SCC-Ag表达水平进行检测能够将化疗效果有效反映出来,进而有效指导临床的下一步治疗工作,从而有效改善患者预后。  相似文献   
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BackgroundGiven numerous publications and clinical trials regarding axillary management in breast cancer, we sought to summarize this complex literature to help clarify this field for clinicians. This systematic review focuses on the role of irradiation of the axillary nodes (locoregional nodal irradiation [LRNI]) in the management of the axilla in patients with early-stage breast cancer in various clinical settings.MethodsWe searched MEDLINE and EMBASE databases, the Cochrane library, the proceedings of the ASCO, the ASTRO, the ESMO, the ESTRO, and the San Antonio Breast Cancer Symposium (2016–2019) meetings. The quality of the studies was assessed with design-specific tools. The study was registered in PROSPERO.ResultsWe included one systematic review, one individual patient data (IPD) meta-analysis, and five randomized controlled trials (RCTs). After axillary lymph node dissection (ALND), LRNI resulted in small benefits in breast cancer specific mortality, locoregional recurrence, and distant metastases-free survival but not overall survival. After a positive sentinel node biopsy (SLNB), LRNI may provide equivalent locoregional control and disease-free survival (DFS) compared to ALND with a lower risk of lymphedema. No randomized data is available for the neoadjuvant setting.ConclusionsThe summary of the role of radiation, is relevant to radiation oncologists for choosing the correct cohort of patient requiring LRNI and to surgeons making clinical decisions regarding the timing and type of breast reconstruction offered to patients.  相似文献   
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Renal cell cancer (RCC) represents 2%-3% of all adulthood cancers and is the most common malignant neoplasm of the kidney (90%). In the mid-nineties of the last century, the standard of treatment for patients with metastatic RCC was cytokines. Sunititib and pazopanib were registered in 2007 and 2009, respectively, and have since been the standard first-line treatment for metastatic clear cell RCC (mccRCC). Renal cell cancer is a highly immunogenic tumor with tumor infiltrating cells, including CD8+ T lymphocytes, dendritic cells, natural killer cells (NK) and macrophages. This observation led to the design of new clinical trials in which patients were treated with immunotherapy. With the growing evidence that proangiogenic factors can have immunomodulatory effects on the host’s immune system, the idea of combining angiogenic drugs with immunotherapy has emerged, and new clinical trials have been designed. In the last few years, several therapeutic options have been approved [immunotherapy and immunotherapy/tyrosine kinase inhibitors (TKI)] for the first-line treatment of mccRCC. Nivolumab/ipilimumab is approved for the treatment of patients with intermediate and poor prognoses. Several checkpoint inhibitors (pembrolizumab, nivolumab, avelumab) in combination with TKI (axitinib, lenvatinib, cabozantinib) are approved for the treatment of patients regardless of their International mRCC Database Consortium prognostic group and PD-L1 expression. There is no specific and ideal biomarker that could help in selecting the ideal patient for the appropriate first-line treatment.  相似文献   
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Oral squamous cell carcinomas (OSCCs) develop in genetically altered epithelium in the mucosal lining, also coined as fields, which are mostly not visible but occasionally present as white oral leukoplakia (OL) lesions. We developed a noninvasive genetic assay using next-generation sequencing (NGS) on brushed cells to detect the presence of genetically altered fields, including those that are not macroscopically visible. The assay demonstrated high accuracy in OL patients when brush samples were compared with biopsies as gold standard. In a cohort of Fanconi anemia patients, detection of mutations in prospectively collected oral brushes predicted oral cancer also when visible abnormalities were absent. We further provide insight in the molecular landscape of OL with frequent changes of TP53, FAT1 and NOTCH1. NGS analysis of noninvasively collected samples offers a highly accurate method to detect genetically altered fields in the oral cavity, and predicts development of OSCC in high-risk individuals. Noninvasive genetic screening can be employed to screen high-risk populations for cancer and precancer, map the extension of OL lesions beyond what is visible, map the oral cavity for precancerous changes even when visible abnormalities are absent, test accuracy of promising imaging modalities, monitor interventions and determine genetic progression as well as the natural history of the disease in the human patient.  相似文献   
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