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Barrett's esophagus (BE) is the precursor to esophageal adenocarcinoma (EAC). Progression to cancer typically occurs in a stepwise fashion through worsening dysplasia and ultimately, invasive neoplasia. Established EAC with deep involvement of the esophageal wall and/or metastatic disease is invariably associated with poor long-term survival rates. This guides the rationale of surveillance of Barrett’s in an attempt to treat lesions at an earlier, and potentially curative stage. The last two decades have seen a paradigm shift in management of Barrett’s with rapid expansion in the role of endoscopic eradication therapy (EET) for management of dysplastic and early neoplastic BE, and there have been substantial changes to international consensus guidelines for management of early BE based on evolving evidence. This review aims to assist the physician in the therapeutic decision-making process with patients by comprehensive review and summary of literature surrounding natural history of Barrett’s by histological stage, and the effectiveness of interventions in attenuating the risk posed by its natural history. Key findings were as follows. Non-dysplastic Barrett’s is associated with extremely low risk of progression, and interventions cannot be justified. The annual risk of cancer progression in low grade dysplasia is between 1%-3%; EET can be offered though evidence for its benefit remains confined to highly select settings. High-grade dysplasia progresses to cancer in 5%-10% per year; EET is similarly effective to and less morbid than surgery and should be routinely performed for this indication. Risk of nodal metastases in intramucosal cancer is 2%-4%, which is comparable to operative mortality rate, so EET is usually preferred. Submucosal cancer is associated with nodal metastases in 14%-41% hence surgery remains standard of care, except for select situations.  相似文献   
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Journal of Public Health - The first Covid-19 cases were reported in Malaysia on 25 January 2019 followed by a quiescent period before an upward swing of the cases at the end of February 2020,...  相似文献   
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First-line chemotherapy for advanced/metastatic human epidermal growth factor receptor 2 (HER2)-negative gastric/gastroesophageal junction cancer (GC/GEJC) has poor median overall survival (OS; <1 year). We report efficacy and safety results from Chinese patients in the phase III global CheckMate 649 study of nivolumab plus chemotherapy vs chemotherapy for the first-line treatment of GC/GEJC/esophageal adenocarcinoma (EAC). Chinese patients with previously untreated advanced or metastatic GC/GEJC/EAC were randomized to receive nivolumab (360 mg Q3W or 240 mg Q2W) plus chemotherapy (XELOX [capecitabine and oxaliplatin] Q3W or FOLFOX [oxaliplatin, leucovorin and 5-fluorouracil] Q2W), nivolumab plus ipilimumab (not reported) or chemotherapy alone. OS, blinded independent central review-assessed progression-free survival (PFS), objective response rate (ORR), duration of response (DOR) and safety are reported. Of 1581 patients enrolled and randomized, 208 were Chinese. In these patients, nivolumab plus chemotherapy resulted in clinically meaningful improvement in median OS (14.3 vs 10.2 months; HR 0.61 [95% CI: 0.44-0.85]), median PFS (8.3 vs 5.6 months; HR 0.57 [95% CI: 0.40-0.80]), ORR (66% vs 45%) and median DOR (12.2 vs 5.6 months) vs chemotherapy, respectively. The safety profile was acceptable, with no new safety signals observed. Consistent with results from the global primary analysis of CheckMate 649, nivolumab plus chemotherapy demonstrated a clinically meaningful improvement in OS and PFS and higher response rate vs chemotherapy and an acceptable safety profile in Chinese patients. Nivolumab plus chemotherapy represents a new standard first-line treatment for Chinese patients with non-HER2-positive advanced GC/GEJC/EAC.  相似文献   
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目的分析多层螺旋CT对腹股沟疝的分型鉴别及应用价值。 方法选择2018年5月至2021年3月于宁国市人民医院外科收治的102例腹股沟疝患者作为研究对象,观察分析多层螺旋CT检查斜疝、直疝、股疝的类型,多层螺旋CT诊断与手术结果对比,多层螺旋CT检查的诊断效能,多层螺旋CT横断位、冠状位及矢状位的诊断符合率,多层螺旋CT检查腹股沟疝的影像学征象。 结果102例患者中单纯性斜疝70例,单纯性直疝20例,单纯性股疝5例,左侧复发性腹股沟直疝2例,右侧嵌顿性腹股沟股疝5例。CT诊断与手术结果相符的斜疝占64.71%(66/102),直疝占16.67%(17/102),股疝占6.86%(7/102)。多层螺旋CT诊断斜疝的特异度、灵敏度、阳性预测值分别为8.33%、91.67%、91.67%;直疝的特异度、灵敏度、阳性预测值分别为15.00%、85.00%、85.00%;股疝的特异度、灵敏度、阳性预测值分别为30.00%、70.00%、70.00%。多层螺旋CT冠状位的诊断符合率为99.02%,稍高于矢状位的98.04%(P>0.05);冠状位的诊断符合率为99.02%,明显高于横断位的75.49%(P<0.05);矢状位的诊断符合率为98.04%,明显高于横断位的75.49%(P<0.05)。102例患者共有疝囊105个,斜疝患者有72个疝囊,直疝患者有23个疝囊,股疝患者有10个疝囊。93.06%(67/72)的斜疝疝囊的腹股沟管内环扩大,直疝及股疝疝囊的腹股沟管内环均正常;斜疝及直疝疝囊均无股三角填塞,股疝疝囊均股三角填塞;斜疝及股疝疝囊均无侧新月征,82.61%(19/23)的直疝疝囊具有侧新月征;斜疝及直疝疝囊位于腹股沟韧带的前方,股疝疝囊均位于腹股沟韧带的后方;90.28%(65/72)的斜疝疝囊壁位于腹壁下动脉的外侧,直疝疝囊壁位于腹壁下动脉的内侧,股疝疝囊壁位于腹壁下动脉的后下方。 结论多层螺旋CT检查有助于腹股沟疝的诊断,与临床对腹股沟区解剖结构的了解相结合,对腹股沟直疝、斜疝及股疝的分型具有重要价值。  相似文献   
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目的:对食管胃结合部腺癌近端胃切除术(PG)人工三角瓣成形后残胃食糜进行流体动力学数值模拟,并计算不同性质胃内食糜的流动特征。方法:构建常规PG和人工三角瓣成形术术后胃仿真模型,运用Fluent软件对不同粘度胃内食糜反流问题进行数值模拟。结果:站立位姿态时,相对常规PG方案,人工三角瓣成形手术方案表现出较好的抗反流作用;卧位姿态时,当胃内食糜粘度大于0.145 2 Pa[?s,且胃内食糜不超过人工三角瓣情况下,人工三角瓣成形抗反流手术表现出较好的抗反流效果;人工三角瓣抗反流成形手术方案数值模拟结果与临床上患者表现一致。结论:本研究仿真分析为人工三角瓣成形抗反流手术方案的有效性机理分析、临床患者术后饮食及手术方案的进一步改进提供理论及数值依据。 【关键词】食管胃结合部腺癌;抗反流;人工三角瓣;计算流体力学  相似文献   
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Recent epidemiological studies suggested that proton pump inhibitor (PPI) use was associated with an increased risk of biliary tract cancer (BTC), however, confounders were not adequately controlled. Our study aimed to evaluate PPI use and subsequent risk of BTC and its subtypes in three well-established cohorts. We conducted a pooled analysis of the subjects free of cancers in UK Biobank (n = 463 643), Nurses' Health Study (NHS, n = 80 235) and NHS II (n = 95 869). Propensity score weighted Cox models were used to estimate marginal HRs of PPIs use on BTC risk, accounting for potential confounders. We documented 284 BTC cases in UK Biobank (median follow-up: 7.6 years), and 91 cases in NHS and NHS II cohorts (median follow-up: 15.8 years). In UK biobank, PPI users had a 96% higher risk of BTC compared to nonusers in crude model (HR 1.96, 95% CI 1.44-2.66), but the effect was attenuated to null after adjusting for potential confounders (HR 0.95, 95% CI 0.60-1.49). PPI use was not associated with risk of BTC in the pooled analysis of three cohorts (HR 0.93, 95% CI 0.60-1.43). We also observed no associations between PPI use with risk of intrahepatic (HR 1.00, 95% CI 0.49-2.04), extrahepatic bile duct (HR 1.09, 95% CI 0.52-2.27) and gallbladder cancers (HR 0.66, 95% CI 0.26-1.66) in UK Biobank. In summary, regular use of PPIs was not associated with the risk of BTC and its subtypes.  相似文献   
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