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BackgroundTumor mutation burden (TMB) as a prognostic marker for immunotherapy has shown prognostic value in many cancers. However, there is no systematic investigation on TMB in papillary thyroid carcinoma (PTC).MethodsBased on the somatic mutation data of 487 PTC patients from The Cancer Genome Atlas (TCGA), TMB was calculated, and we classified the samples into high-TMB (H-TMB) and low-TMB (L-TMB) groups. Bioinformatics methods were used to explore the characteristics and potential mechanism of TMB in PTC.ResultsHigh TMB predicts shorter progression-free survival (PFS) (P < 0.001). TMB was positively correlated with age, stage, tumor size, metastasis, the male sex and tall cell PTC. Compared to the L-TMB group, the H-TMB group presented with lower immune cell infiltration, a higher proportion of tumor-promoting immune cells (M0 macrophages, activated dendritic cells and monocytes) and a lower proportion of antitumor immune cells (M1 macrophages, CD8+ T cells and B cells). Additionally, the characteristics displayed by different TMB groups were not driven by critical driver mutations such as BRAF and RAS.ConclusionsPTC patients with high TMB have a worse prognosis. By stratifying PTC patients according to their TMB, advanced PTC patients who are candidates for immunotherapy could be selected. 相似文献
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目的探究肿瘤坏死因子-α(Tumornecrosis factor-α,TNF-α)-308基因对导管相关性脓毒症(Catheter related sepsis,CRS)患者病情的影响,旨在为临床治疗CRS提供科学依据。方法选取2017年7月-2018年10月于浙江大学医学院附属杭州市第一人民医院接受治疗的86例CRS患者为研究对象,按照是否并发多器官功能障碍综合征将患者分为试验组和对照组,对照组共48例,未并发多器官功能障碍综合征,试验组共38例,并发多器官功能障碍综合征,分析两组患者TNF-α-308基因多态性差异,使用多因素Logistic回归分析CRS患者并发多器官功能障碍综合征的危险因素。结果试验组GA基因型频率34.21%、AA基因型频率50.00%、高G等位基因频率18.42%均高于对照组,GG基因型频率52.63%、A等位基因频率28.95%均低于对照组,差异均具有统计学意义(P<0.05);多因素Logistic回归分析结果显示,低GG基因型频率、低G等位基因频率、高GA基因型频率、高AA基因型频率、高A等位基因频率是CRS患者并发多器官功能障碍综合征的危险因素(P<0.05)。结论TNF-α-308基因与CRS患者病情密切相关,GG基因型频率和G等位基因频率降低,GA基因型频率、AA基因型频率、A等位基因频率升高会加重患者的病情,增加多器官功能障碍综合征的发生风险,临床上应该加以重视。 相似文献
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目的观察膀胱肿瘤切除术后患者尿路感染发生情况与病原学特征,分析诱发尿路感染的危险因素,并提出合理且具备针对性的冲洗对策,为未来膀胱肿瘤切除术后尿路感染的预防提供合理参考。方法回顾性分析连云港市第一人民医院2016年1月-2019年1月接受经尿道膀胱肿瘤切除术治疗的451例膀胱肿瘤患者的临床资料,收集患者病例资料,全部患者术后均定期取尿液标本进行细菌培养,参照相关标准判定患者尿路感染情况,记录患者一般情况,包括一般人口学资料(性别、年龄、体质量、受教育程度等),同时记录患者糖尿病的疾病合并情况,将术后尿路感染可能的危险因素纳入初步分析,Logistic多因素回归分析膀胱肿瘤切除术后发生尿路感染的危险因素。结果451例膀胱肿瘤切除术患者术后第3天尿液中细菌培养阳性例数为80例,阳性率为17.74%,在使用抗菌药物后,患者尿液中细菌培养阳性率逐渐降低,各时点尿液细菌阳性培养率比较,差异有统计学意义(P<0.05);经多因素Logistic回归分析检验证实,高龄、血糖水平控制不佳、术前留置导尿管、多发肿瘤是膀胱肿瘤切除术后尿路感染的危险因素(OR>1,P<0.05);80例术后尿液细菌培养阳性患者共分离出87株菌株,其中革兰阴性菌66株占75.86%,革兰阳性球菌21株占24.14%。结论膀胱肿瘤切除术后患者有较高的尿路感染风险,革兰阴性菌是主要的感染病原菌,年龄、基础疾病、肿瘤位点、术前导尿管留置等是影响因素,这类患者应引起临床高度重视。 相似文献
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《Diagnostic and interventional imaging》2020,101(12):821-830
PurposeTo compare morphological imaging features and CT texture histogram parameters between grade 3 pancreatic neuroendocrine tumors (G3-NET) and neuroendocrine carcinomas (NEC).Materials and methodsPatients with pathologically proven G3-NET and NEC, according to the 2017 World Health Organization classification who had CT and MRI examinations between 2006-2017 were retrospectively included. CT and MRI examinations were reviewed by two radiologists in consensus and analyzed with respect to tumor size, enhancement patterns, hemorrhagic content, liver metastases and lymphadenopathies. Texture histogram analysis of tumors was performed on arterial and portal phase CT images. images. Morphological imaging features and CT texture histogram parameters of G3-NETs and NECs were compared.ResultsThirty-seven patients (21 men, 16 women; mean age, 56 ± 13 [SD] years [range: 28-82 years]) with 37 tumors (mean diameter, 60 ± 46 [SD] mm) were included (CT available for all, MRI for 16/37, 43%). Twenty-three patients (23/37; 62%) had NEC and 14 patients (14/37; 38%) had G3-NET. NECs were larger than G3-NETs (mean, 70 ± 51 [SD] mm [range: 18 - 196 mm] vs. 42 ± 24 [SD] mm [range: 8 - 94 mm], respectively; P = 0.039), with more tumor necrosis (75% vs. 33%, respectively; P = 0.030) and lower attenuation on precontrast (30 ± 4 [SD] HU [range: 25-39 HU] vs. 37 ± 6 [SD] [range: 25-45 HU], respectively; P = 0.002) and on portal venous phase CT images (75 ± 18 [SD] HU [range: 43 - 108 HU] vs. 92 ± 19 [SD] HU [range: 46 - 117 HU], respectively; P = 0.014). Hemorrhagic content on MRI was only observed in NEC (P = 0.007). The mean ADC value was lower in NEC ([1.1 ± 0.1 (SD)] × 10−3 mm2/s [range: (0.91 - 1.3) × 10−3 mm2/s] vs. [1.4 ± 0.2 (SD)] × 10−3 mm2/s [range: (1.1 - 1.6) × 10−3 mm2/s]; P = 0.005). CT histogram analysis showed that NEC were more heterogeneous on portal venous phase images (Entropy-0: 4.7 ± 0.2 [SD] [range: 4.2-5.1] vs. 4.5 ± 0.4 [SD] [range: 3.7-4.9]; P = 0.023).ConclusionPancreatic NECs are larger, more frequently hypoattenuating and more heterogeneous with hemorrhagic content than G3-NET on CT and MRI. 相似文献
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ObjectivePrevious studies on glioblastomas (GBMs) have not reached a consensus on peritumoral edema (PTE)’s influence on survival. This study evaluated the PTE index’s prognostic role in newly diagnosed GBMs using a well-designed method.MethodsSelected patients were reviewed after a rigorous screening process. Their general information was obtained from electronic medical records. The imaging metrics (MTD, TTM, TTE) representing tumor diameter, laterality, and PTE extent were obtained by manual measurement in Syngo FastView software. The PTE index was a ratio of TTE to MTD. Multiple variables were evaluated using analysis of variance and Cox regression model.ResultsOf 143 patients, 62 were included in this study. MGMT promoter methylation and tumor laterality were both independent prognostic factors (p = 0.020, 0.042; HR = 0.272, 2.630). The lateral tumors’ index was higher than that of the medial tumors (57.7% vs. 42.6%, p = 0.027). Low-index tumors were located in relatively medial positions compared with high-index tumors (TTM, 4.9 vs. 12.8, p = 0.032). This finding indicated that the PTE index tended to increase with tumor laterality. Moreover, the patients with low-index tumors had a significant survival disadvantage in the univariate analysis but not in the multivariate analysis (p = 0.023, 0.220). However, further analysis found that the combination of tumor laterality and PTE statistically stratified the survival outcome. The patients with lateral high-index tumors survived significantly longer (p = 0.022, HR = 1.927).ConclusionsIn contrast with the previous studies, this study recommends combining PTE and tumor laterality for survival stratification in newly diagnosed GBMs. 相似文献