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1.
PurposeThe purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC).Materials and MethodsEighty-nine patients with AIP (65 men, 24 women; mean age, 59.7 ± 13.9 [SD] years; range: 21–83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1 ± 12.3 [SD] years; range: 36–86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5 mm thickness/increment) were compared with thick-slices images (3 or 5 mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing.ResultsThe pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8–100%), 83.9% (52:67; 95% CI: 74.7–93.0%) and 77.4% (48/62; 95% CI: 67.0–87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6–100%) and 100% specificity (33/33; 95% CI: 93–100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8–100%) and area under the curve of 0.975 (95% CI: 0.936–1.0).ConclusionsRadiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%.  相似文献   
2.
BackgroundSurgical resection is recommended for patients with resectable acinar cell carcinoma (ACC). The aim of this study was to investigate the clinical characteristics and surgical outcomes of resectable ACC in comparison to pancreatic ductal adenocarcinoma (PDAC).MethodA retrospective analysis was performed on all patients who consecutively underwent radical resection with pathologically confirmed ACC and PDAC from December 2011 to December 2018. Clinicopathologic characteristics and follow-up information were analyzed. A 1:3 propensity score matching (PSM) method was used to minimize the bias between ACC and PDAC.ResultsA total of 26 patients with ACC and 1351 with PDAC were included. Compared to PDAC, ACC tended to be larger (4.5 vs. 3.0 cm; p < 0.001) and more frequently located in the pancreatic body/tail (61.5% vs. 36.6%, p = 0.009), with lower total bilirubin levels, lower neutrophil lymphocyte ratio (NLR) levels and lower carbohydrate antigen 19-9 (CA19-9) levels and carcinoembryonic antigen (CEA) levels. There was no difference in postoperative morbidities in patients with ACC and PDAC. The median OS and RFS were longer in ACC when compared to PDAC (OS: 43.5 mo vs. 19.0 mo, p = 0.004; RFS: 24.5 mo vs. 11.6 mo, p = 0.023). After the 1:3 PSM, ACC remained to be a better histological type for OS (p = 0.024), but had comparable RFS with PDAC (p = 0.164).ConclusionPatients with ACC after radical resection had better OS than that with PDAC. However, ACC is also an aggressive tumor with a similar trend of RFS with PDAC after the matching, necessitating the multidisciplinary treatment for resectable ACC disease.  相似文献   
3.
胰腺导管腺癌(pancreatic ductal adenocarcinoma,PDAC)是最常见的胰腺恶性肿瘤,其恶性程度高,患者生存率低。CT、MR是PDAC诊断最常用的影像检查,其不仅可以帮助PDAC进行诊断、鉴别,还能通过特殊序列来提供相应功能参数。此外,影像组学可以挖掘更多的影像信息供临床医生分析、预测患者术后生存率。CT、MR对于PDAC临床治疗具有重要的指导意义,故本文对PDAC相关CT、MR进展进行综述。  相似文献   
4.
Background and aimPatient decision aids for oncological treatment options, provide information on the effect on recurrence rates and/or survival benefit, and on side-effects and/or burden of different treatment options. However, often uncertainty exists around the probability estimates for recurrence/survival and side-effects which is too relevant to be ignored. Evidence is lacking on the best way to communicate these uncertainties. The aim of this study is to develop a method to incorporate uncertainties in a patient decision aid for breast cancer patients to support their decision on radiotherapy.MethodsFirstly, qualitative interviews were held with patients and health care professionals. Secondly, in the development phase, thinking aloud sessions were organized with four patients and 12 health care professionals, individual and group-wise.ResultsConsensus was reached on a pictograph illustrating the whole range of uncertainty for local recurrence risks, in combination with textual explanation that a more exact personalized risk would be given by their own physician. The pictograph consisted of 100 female icons in a 10 x 10 array. Icons with a stepwise gradient color indicated the uncertainty margin. The prevalence and severity of possible side-effects were explained using verbal labels.ConclusionsWe developed a novel way of visualizing uncertainties in recurrence rates in a patient decision aid. The effect of this way of communicating risk uncertainty is currently being tested in the BRASA study (NCT03375801).  相似文献   
5.
人胰胆管合流异常胆汁对胆管细胞的影响及其机理探讨   总被引:1,自引:0,他引:1  
目的研究胰胆管合流异常(APBDU)患者的胆汁对人胆管细胞生长的影响,探讨APBDU与胆管癌发生的关系。方法应用四甲基偶氮唑蓝(MTT)比色法检测APBDU患者胆汁对胆管细胞增殖的影响,流式细胞仪测定其细胞周期分布及凋亡情况;Western blot法检测经APBDU胆汁处理的胆管细胞c-erbB-2蛋白表达水平的变化。结果APBDU患者胆汁与正常对照胆汁比较,能明显促进胆管细胞的增殖(P<0.05),这种促增殖作用可被环氧化酶COX-2抑制剂celecoxib或一氧化氮合成酶抑制剂L-NAME抑制;流式细胞仪分析经APBDU胆汁处理的胆管细胞其处于S期的细胞明显增多(P<0.001);Western blot法检测经APBDU胆汁处理的胆管细胞其c-erbB-2表达增多。结论APBDU患者的胆汁对正常胆管细胞增殖有促进作用,可能潜在致癌活性。  相似文献   
6.
After removal of intraductal stones, a 10‐Fr or 7‐Fr pancreatic stent was placed in 16 patients with upstream ductal dilation proximal to a stricture of the main pancreatic duct. Stents were removed after a mean duration of 52.5 days. Nine patients underwent repeated stenting. About one year after removal of the initial stent, when the remaining upstream ductal dilation was found on follow‐up pancreatograms, the next stent was replaced. Repeated stenting improved outflow of pancreatic juice more effectively than one‐time stenting. Correlation between long‐term pain relief without recurrence of intraductal stones and reduction of duct diameter was also shown. Stent occlusion was observed in 14 of 30 stents. Stent occlusion was frequently associated with recurrence of pancreatitis and intraductal stones, and was also associated with morphologic changes in the pancreatic ductal system. Although there were no significant differences between stent patency of the initial stents and that of the next stents, stent patency of 10‐Fr stents was superior to that of 7‐Fr stents. 10‐Fr stents should be removed within 8 weeks and 7‐Fr stents should be removed within 4 weeks for the prevention of stent occlusion. Repeated stenting with short‐term stenting is therefore considered a safe and effective protocol of endoscopic pancreatic stenting.  相似文献   
7.
目的 :探讨癌蛋白 (C erbB 2 )和基质金属蛋白酶 (MMP2 )在乳腺浸润性导管癌中的表达及相互关系。方法 :应用免疫组织化学S -P法对 5 6例乳腺浸润性导管癌的C erbB 2和MMP2的阳性表达进行检测分析。结果 :5 6例中有 37例 (6 6 % )C erbB 2过表达 ,39例 (6 9.6 % )MMP2过表达 ,C erbB 2和MMP2同时阳性表达者 32例(5 7 1% )。两者阳性率均随组织学分级升高而上升 ,但各级间未见明显差异 (P >0 .0 5 )。在转移组中 ,88.9% (2 4 /2 7)的病例C erbB 2过表达 ,85 .2 % (2 3/ 2 7)MMP2过表达 ,两者的过表达与转移呈正相关关系 (PC erbB 2 =0 .0 0 1,PMMP2 =0 .0 15 )。C erbB 2和MMP2阳性配对分析表明 ,两者间阳性表达互为正相关 (P <0 .0 0 5 ,r=0 .5 1)。结论 :在乳腺浸润性导管癌中 ,C erbB 2和MMP2的过表达提示转移增加 ,可以作为乳腺癌的预后指标。  相似文献   
8.
目的 探讨乳腺癌广泛导管内癌成分(extensive intraductal component,EIC)、粉刺状坏死(comedo necrosls)、组织学分级与组织蛋白酶D(eathepsin D)、Kiab7、单链DNA(ssDNA)及c-erbB-2表达的关系。方法检测日本德岛乳腺门诊与东德岛医院1996年1月至1997年4月连续手术切除的59例乳腺浸润性导管癌标本。用免疫组化方法,检测59例乳腺浸润性导管癌中组织蛋白酶D(eathepsin D)、Ki-67、单链DNA及c-erbB-2的表达。结果EIC阳性组,肿瘤上皮细胞中的组织蛋白酶D为高表达(P=0.021),肿瘤间质细胞中的组织蛋白酶D表达差异无显著性意义。粉刺状坏死的出现,与c-erbB-2癌基因、肿瘤上皮细胞中的组织蛋白酶D和细胞增殖指数相关(P分别为0.042,0.006及0.013)。结论肿瘤上皮细胞中的组织蛋白酶D可能参与了EIC与粉刺状坏死的形成。EIC与粉刺状坏死的检测有临床应用价值。  相似文献   
9.
In this review article, we demonstrate the mucin expression profile in normal tissue, invasive ductal carcinoma (IDC), two subtypes of intraductal papillary–mucinous neoplasm (IPMN dark cell type and IPMN clear cell type), pancreatic intraepithelial neoplasia (PanIN), and mucinous cystic neoplasm (MCN) of the pancreas. In MUC1, there are various glycoforms, such as poorly glycosylated MUC1, sialylated MUC1, and fully glycosylated MUC1. IDCs showed high expression of all the glycoforms of MUC1. IPMNs dark cell type showed no expression or low expression of all the glycoforms of MUC1. IPMNs clear cell type showed low expression of poorly glycosylated MUC1, but expression of sialylated MUC1 and fully glycosylated MUC1. Expression of MUC2 was negative in IDCs, high in IPMNs dark cell type and low in IPMNs clear cell type. MUC5AC was highly expressed in IDCs, IPMNs dark cell type, and IPMNs clear cell type. MUC6 expression was higher in IPMNs clear cell type than in IDCs and IPMNs dark cell type. Our recent study demonstrated that high expression of MUC4 in IDCs is correlated with a poor outcome for patients. In PanINs, expression of both MUC5AC and MUC6 are an early event, whereas up-regulation of MUC1 is a late event. MCNs do not look as if they will show a specific mucin expression profile according to the literature review.  相似文献   
10.
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