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1.
ObjectiveTo evaluate the performance of a deep learning (DL)-based radiomics strategy on contrast-enhanced computed tomography (CT) to predict microvascular invasion (MVI) status and clinical outcomes, recurrence-free survival (RFS) and overall survival (OS) in patients with early stage hepatocellular carcinoma (HCC) receiving surgical resection.MethodsAll 283 eligible patients were included retrospectively between January 2008 and December 2015, and assigned into the training cohort (n = 198) and the testing cohort (n = 85). We extracted radiomics features via handcrafted radiomics analysis manually and DL analysis of pretrained convolutional neural networks via transfer learning automatically. Support vector machine was adopted as the classifier. A clinical-radiological model for MVI status integrated significant clinical features and the radiological signature generated from the radiological model with the optimal area under the receiver operating characteristics curve (AUC) in the testing cohort. Otherwise, DL-based prognostic models were constructed in prediction of recurrence and mortality via Cox proportional hazard analysis.ResultsThe clinical-radiological model for MVI represented an AUC of 0.909, accuracy of 96.47%, sensitivity of 90.91%, specificity of 97.30%, positive predictive value of 83.33%, and negative predictive value of 98.63% in the testing cohort. The clinical-radiological models for identification of RFS and OS outperformed prediction performance of the clinical model or the DL signature alone. The DL-based integrated model for prognostication showed great predictive value with significant classification and discrimination abilities after validation.ConclusionsThe integrated DL-based radiomics models achieved accurate preoperative prediction of MVI status, and might facilitate predicting tumor recurrence and mortality in order to optimize clinical decisions for patients with early stage HCC.  相似文献   
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姚刚  曹新岭  李涛 《中国全科医学》2022,25(12):1429-1434
背景 既往对肝癌微血管侵犯病理诊断的重要性重视不够,目前国内外缺乏对微血管侵犯统一的病理诊断标准,也未将微血管侵犯列为病理常规诊断指标。C反应蛋白/白蛋白比值(CAR)作为新型系统性炎性因子,与肝癌的增殖、侵袭转移等恶性生物学行为密切相关。 目的 探讨CAR预测单发小肝癌患者微血管侵犯的价值。 方法 选择2017年6月至2021年6月在新疆医科大学第一附属医院行肝切除术的单个、肿瘤直径≤5 cm的术后病理检查证实为肝癌的患者346例为研究对象。收集患者一般资料,并计算CAR。绘制CAR预测单发小肝癌患者微血管侵犯的受试者工作特征(ROC)曲线,并计算CAR的最佳诊断截点,根据CAR最佳诊断截点将患者进行分组,采用1∶1最近邻居倾向性评分匹配(PSM)法将Logistic模型估计的倾向性评分相近患者进行配对,得到两组间各临床特征比较均衡性较高的样本。比较匹配后两组患者微血管侵犯率,采用Logistic回归分析评估匹配前、后CAR对单发小肝癌患者微血管侵犯的预测价值。 结果 346例患者中微血管侵犯阳性131例(37.9%),微血管侵犯阴性215例(62.1%)。ROC曲线分析结果显示,CAR预测单发小肝癌患者微血管侵犯的灵敏度为82.9%,特异度为76.4%,ROC曲线下面积为0.787〔95%CI(0.697,0.877)〕,最佳诊断截点为0.03。根据CAR最佳诊断截点,将患者分为CAR<0.03组(A组,n=145)和CAR≥0.03组(B组,n=201)。采用1∶1最近邻居PSM法,共92对匹配成功,匹配后两组临床资料均衡。匹配后,B组患者微血管侵犯发生率〔43.5%(40/92)〕高于A组〔13.0%(12/92)〕(χ2=6.314,P=0.013)。采用3种Logistic回归分析结果显示,匹配前、后CAR均为单发小肝癌患者微血管侵犯的独立影响因素(P<0.05)。 结论 CAR作为新型系统性炎症指标,可用于预测单发小肝癌微血管侵犯,当CAR≥0.03时提示单发小肝癌微血管侵犯发生率较高。  相似文献   
3.
BackgroundWhereas the usefulness of radiofrequency (RF) energy as haemostatic method in liver surgery has become well established in the last decades, its intentional application on resection margins with the aim of reducing local recurrence is still debatable. Our goal was to compare the impact of an additional application of RF energy on the top of the resection surface, namely additional margin coagulation (AMC), on local recurrence (LR) when subjected to a subcentimeter margin.MethodsWe retrospectively analyzed 185 patients out of a whole cohort of 283 patients who underwent radical hepatic resection with subcentimetric margin. After propensity score adjustment, patients were classified into two balanced groups according to whether RF was applied or not.ResultsNo significant differences were observed within groups in baseline characteristics after PSM adjustment. The LR rate was significantly higher in the Control than AMC Group: 12 patients (14.5%) vs. 4 patients (4.8%) (p = 0.039). The estimated 1, 3, and 5-year LR-free survival rates of patients in the Control and AMC Group were: 93.5%, 86.0%, 81.0% and 98.8%, 97.2%, 91.9%, respectively (p = 0.049). Univariate Cox analyses indicated that the use of the RF applicator was significantly associated with lower LR (HR = 0.29, 95% confidence interval 0.093–0.906, p = 0.033). The Control Group showed smaller coagulation widths than the AMC group (p < 0.001).ConclusionsAn additional application of RF on the top of the resection surface is associated with less local hepatic recurrence than the use of conventional techniques.  相似文献   
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Although recent studies revealed that adipose tissue accelerates pancreatic tumor progression with excessive extracellular matrix, key players for desmoplasia in the adipose microenvironment remains unknown. Here, we investigated the roles of adipose tissue-derived stromal cells (ASCs) in desmoplastic lesions and tumor progression by in vitro and in vivo experiments. In a three-dimensional (3-D) organotypic fat invasion model using visceral fat from CAG-EGFP mice, GFP-positive fibroblastic cells infiltrated toward cancer cells. When tumor cells were inoculated into transplanted visceral fat pads in vivo, tumor weights and stromal components were enhanced compared to subcutaneous and orthotopic tumor cells inoculated without fat pads. Expression of αSMA in established human ASCs was lower compared to cancer associated fibroblasts, and the 3-D collagen matrices produced by ASCs cultured in cancer cell-conditioned medium changed from loose to dense structures that affected the motility of cancer cells. Microarray analyses revealed upregulation of S100A4 in ASCs, while S100A4-positive stromal cells were observed at extrapancreatic invasion sites of human pancreatic cancer. The present findings indicate that ASCs are recruited to extrapancreatic invasion sites and produce dense collagen matrices that lead to enhanced tumor progression. Both inhibition of ASCs recruitment and activation could lead to a novel antistromal therapy.  相似文献   
8.
Epithelial cell polarity regulator Crumbs3 (Crb3), a mammalian homolog within the Drosophila Crb gene family, was initially identified as an essential embryonic development factor. It is recently implicated in tumor suppression, though its specific functions are controversial. We here demonstrate that Crb3 strongly promotes tumor invasion and metastasis of human colon adenocarcinoma cells. Crb3 centrality to tumor migration was supported by strong expression at invasive front and metastatic foci of colonic adenocarcinoma of the patient tissues. Accordingly, two different Crb3-knockout (KO) lines, Crb3-KO (Crb3 −/−) DLD-1 and Crb3-KO WiDr from human colonic adenocarcinomas, were generated by the CRISPR-Cas9 system. Crb3-KO DLD-1 cells exhibited loss of cellular mobility in vitro and dramatic suppression of liver metastases in vivo in contrast to the wild type of DLD-1. Unlike DLD-1, Crb3-KO WiDr mobility and metastasis were unaffected, which were similar to wild-type WiDr. Proteome analysis of Crb3-coimmunopreciptated proteins identified different respective fibroblast growth factor receptor (FGFR) isotypes specifically bound to Crb3 isoform a through their intracellular domain. In DLD-1, Crb3 showed membranous localization of FGFR1 leading to its functional activation, whereas Crb3 bound to cytoplasmic FGFR4 in WiDr without FGFR1 expression, leading to cellular growth. Correlative expression between Crb3 and FGFR1 was consistently detected in primary and metastatic colorectal cancer patient tissues. Taking these together, Crb3 critically accelerates cell migration, namely invasion and metastasis of human colon cancers, through specific interaction to FGFR1 on colon cancer cells.  相似文献   
9.
目的:探讨甘草酸(GA)通过调控miR-142/锌指E 盒结合的同源盒蛋白1(ZEB1)分子轴对非小细胞肺癌(NSCLC)HCC827 和A549 细胞增殖、侵袭和迁移的影响。方法:HCC827 和A549 细胞培养和转染完成后,分成4 组:NC组(未经转染+3mmol/L GA)、miR-142 inhibitor 组(敲降miR-142+3 mmol/L GA)、pcDNA3.1-ZEB1 组(过表达ZEB1+3 mmol/L GA)和pcDNA3.1-ZEB1+miR-142 mimic 组(过表达ZEB1 及miR-142+3 mmol/L GA)。采用qPCR检测不同浓度GA处理后HCC827 和A549 细胞中miR-142 的表达水平,WB实验检测HCC827 和A549 细胞中ZEB1 蛋白的表达水平,采用MTT和Transwell 检测HCC827 和A549细胞的增殖、侵袭和迁移能力,采用双荧光素酶报告基因检测miR-142 与ZEB1 的靶向关系。结果:GA显著抑制HCC827 和A549 细胞的增殖、侵袭和迁移,且显著上调miR-142 的表达水平(P<0.05 或P<0.01);miR-142 通过靶向结合ZEB1 的3''-UTR 区域下调ZEB1 的表达水平(P<0.05 或P<0.01);进一步实验证实,GA通过上调miR-142 抑制ZEB1 的表达水平,进而抑制HCC827 和A549 细胞增殖、侵袭和迁移(P<0.05 或P<0.01)。结论:GA能够抑制NSCLC HCC827 和A549 细胞增殖、侵袭和迁移,其机制为GA通过上调miR-142对ZEB1 的抑制作用,从而抑制HCC827和A549 细胞的恶性生物学行为。  相似文献   
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Renal cell carcinoma (RCC) is unusual among cancers in that it often grows as a spherical, well‐circumscribed mass. Increasing tumour size influences the pathological pT stage category within pT1 and pT2, with cutoffs of 40, 70 and 100 mm; however, with increasing size also comes a sharp increase in the likelihood of renal sinus or renal vein tributary invasion, such that clear cell RCC rarely reaches 70 mm without invading one of these. To clarify some previous challenges in assigning tumour stage, the American Joint Committee on Cancer 2016 tumor–node–metastasis classification has removed the requirements than vein invasion be recognised grossly and that vein walls contain muscle for the diagnosis of vein invasion. Renal pelvis invasion has also been added as an additional route to pT3a. Multinodularity or finger‐like extensions from a renal mass should be viewed with great suspicion for the possibility of vein or renal sinus invasion, and, as tumour size increases to over 40–50 mm, thorough sampling of the renal sinus interface should always be undertaken. With increasing interest in adjuvant therapy in renal cancer, the pathologist's role in RCC staging will continue to be an important prognostic parameter and a tool for selection of patients for enrolment in clinical trials.  相似文献   
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