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To evaluate the cost–utility of pembrolizumab versus chemotherapy as the first-line setting for metastatic nonsmall cell lung cancer (NSCLC) from the US health care system perspective, a Markov model was developed to compare the lifetime cost and effectiveness of pembrolizumab versus chemotherapy for untreated metastatic NSCLC, based on the clinical data derived from phase III randomized controlled trial (KEYNOTE- 042; ClinicalTrials.gov; NCT02220894). Weibull distribution was fitted to simulate the parametric survival functions. Drug costs were collected from official websites, and utility values were obtained from published literature. Total costs, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratios (ICERs) were computed as primary output indicators. The impact of different PD-L1 expression levels on ICER was also evaluated. One-way and probabilistic sensitivity analyses were performed to assess the model uncertainty. Compared with chemotherapy, patients treated with pembrolizumab provided an additional 1.13, 1.01, and 0.59 QALYs in patients with PD-L1 expression levels of ≥50%, ≥20%, and ≥1%, with corresponding incremental cost of $53,784, $47,479, and $39,827, respectively. The resultant ICERs of pembrolizumab versus chemotherapy were $47,596, $47,184, and $68,061/QALY, in three expression levels of PD-L1, respectively, all of which did not exceed the WTP threshold of 180,000/QALY. Probability sensitivity analysis outcome supported that pembrolizumab exhibited evident advantage over chemotherapy to be cost-effective. One-way sensitivity analysis found that ICERs were most sensitive to utility value of pembrolizumab in progression survival state. All the adjustment of parameters did not qualitatively change the result. For treatment-naive, metastatic NSCLC patients with PD-L1+, pembrolizumab was estimated to be cost-effective compared with chemotherapy for all PD-L1 expression levels at a WTP threshold of $180,000/QALY in the context of the US health care system.  相似文献   
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Objective

Hypertonic saline (HTS) has potent immune and vascular effects. We assessed recipient pretreatment with HTS on allograft function in a porcine model of heart transplantation and hypothesized that HTS infusion would limit endothelial and left ventricular (LV) dysfunction following transplantation.

Methods

Heart transplants were performed after 6 hours of cold ischemic storage. Recipient pigs were randomized to treatment with or without HTS (7.5% NaCl) before cardiopulmonary bypass (CPB). Using a myograft apparatus, coronary artery endothelial-dependent (Edep) and -independent (Eind) relaxation was assessed. LV performance was determined using pressure-volume loop analysis. Pulmonary interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α expression was measured.

Results

Weaning from CPB and LV performance after transplantation were improved in HTS-treated animals. Successful weaning from CPB was greater in the HTS-treated hearts (8 of 8 vs 2 of 8; P < .05). Mean LV functional recovery was improved in the HTS-treated animals, as assessed by preload recruitable stroke work (65 ± 10% vs 27 ± 10%; P < .001) and end-systolic elastance (55 ± 7% vs 37 ± 4%; P < .001). Treatment with HTS resulted in improved Edep (mean maximum elastance [Emax], 56 ± 5% vs 37 ± 7%; P < .001) and Eind (mean Emax%, 77 ± 6% vs 52 ± 4%; P < .001) vasorelaxation compared with control. Pulmonary expression of IL-2, IL-6, and TNF-α increased following transplantation, whereas HTS therapy attenuated IL production (P < .001). Transplantation increased plasma TNF-α levels and LV TNF-α expression, whereas HTS prevented this up-regulation (P < .001).

Conclusions

Recipient HTS pretreatment preserves allograft vasomotor and LV function, and HTS therapy limits CPB-induced injury. HTS may be a novel recipient intervention to prevent graft dysfunction.  相似文献   
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癌性肠梗阻(MBO)是指原发性或转移性恶性肿瘤本身及其抗肿瘤治疗引起的肠梗阻,是晚期肿瘤患者的常见并发症,总体发生率3%~15%。目前,MBO的治疗仍缺乏统一、有效的治疗规范,大多数医院都采用对症处理的。本文在总结数百例治疗经验基础上,提炼出“减(压)、加(营养)、抑(制消化液分泌)、激(素)、利(尿)、动(运动及促进肠蠕动)”六字方针,简单、实用、有效,通过临床观察,该方案能改善患者症状,恢复经口进食率,提高生活质量和手术治疗的机会,缩短住院时间及降低治疗费用,尽管尚缺乏前瞻性的随机对照研究结果,仍值得推广。  相似文献   
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目的应用染色体微阵列分析(chromosome microarray analysis,CMA)技术对1例超声结构异常胎儿进行全基因组拷贝数变异(copy number variations,CNVs)检测,探讨CMA在超声结构异常胎儿产前诊断中的意义。方法应用常规G显带染色体核型分析胎儿及其父母的染色体核型,应用CMA技术分析胎儿及其父母的CNVs。结果G显带核型分析显示胎儿核型与母亲一致,为46,XN,t(8;11)(q21.2;q13)mat,父亲核型正常;父母CMA检测结果均未见异常;胎儿的检测结果为arr[GRCh37]8q13.3(71314082-73322915)×1,提示一条8号染色体的8q13.3区域发生2.00 Mb缺失。结论超声结构异常胎儿染色体核型分析检出的平衡易位,需借助CMA等技术进一步确定是否存在微缺失微重复。  相似文献   
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