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排序方式: 共有946条查询结果,搜索用时 15 毫秒
1.
PurposeTo investigate the reproducibility of diffusion-weighted (DW) MRI and 18F-Fluorodeoxyglucose (18F-FDG)-Positron emission tomography/CT (PET/CT) in monitoring response to neoadjuvant chemotherapy in epithelial ovarian cancer.Materials and methodsTen women (median age, 67 years; range: 41.8–77.3 years) with stage IIIC-IV epithelial ovarian cancers were included in this prospective trial (NCT02792959) between 2014 and 2016. All underwent initial laparoscopic staging, four cycles of carboplatine-paclitaxel-based chemotherapy and interval debulking surgery. PET/CT and DW-MRI were performed at baseline (C0), after one cycle (C1) and before surgery (C4). Two nuclear physicians and two radiologists assessed five anatomic sites for the presence of ≥ 1 lesion. Target lesions in each site were defined and their apparent diffusion coefficient (ADC), maximal standardized uptake value (SUV-max), SUV-mean, SUL-peak, metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were monitored (i.e., 10 patients × 5 sites × 3 time-points). Their relative early and late changes were calculated. Intra/inter-observer reproducibilities of qualitative and quantitative analysis were estimated with Kappa and intra-class correlation coefficients (ICCs).ResultsFor both modalities, inter- and intra-observer agreement percentages were excellent for initial staging but declined later for DW-MRI, leading to lower Kappa values for inter- and intra-observer variability (0.949 and 1 at C0, vs. 0.633 and 0.643 at C4, respectively) while Kappa values remained > 0.8 for PET/CT. Inter- and intra-observer ICCs were > 0.75 for SUV-max, SUL-peak, SUV-mean and their change regardless the time-point. ADC showed lower ICCs (range: 0.013–0.811). ANOVA found significant influences of the evaluation time, the measurement used (ADC, SUV-max, SUV-mean, SUV-max, SUL-peak, MTV or TLG) and their interaction on ICC values (P = 0.0023, P< 0.0001 and P =0.0028, respectively).ConclusionWhile both modalities demonstrated high reproducibility at baseline, only SUV-max, SUL-peak, SUV-mean and their changes maintained high reproducibility during chemotherapy.  相似文献   
2.
PurposeTo compare the safety and efficacy of transarterial chemoembolization for hepatocellular carcinoma (HCC) in patients with and without transjugular intrahepatic portosystemic shunts (TIPS).Materials and MethodsThis single-institution study included a retrospective review of 50 patients who underwent transarterial chemoembolization for HCC between January 2010 and April 2017. Twenty-five patients had preexisting TIPS, and 25 patients were selected to control for age, sex, and target tumor size. Baseline median Model for End-Stage Liver Disease (MELD; 13 TIPS, 9 control; P < .001) and albumin-bilirubin (ALBI; 3 TIPS, 2 control; P < .001) differed between groups. Safety was assessed on the basis of Common Terminology Criteria for Adverse Events (CTCAE) and change in MELD and ALBI grade assessed between 3 and 6 months. Efficacy was assessed by tumor response and time to progression (TTP).ResultsThere was 1 severe adverse event (CTCAE grade >2) in the TIPS group. There was no difference in the change in MELD or ALBI grade. Although there was no difference in tumor response (P = .19), more patients achieved a complete response in the control group (19/25, 76%) than in the TIPS group (13/25, 52%). There was no difference in TTP (P = .82). At 1 year, 2 patients in the control group and 3 patients in the TIPS group received a liver transplant. Seven patients died in the TIPS group.ConclusionsTransarterial chemoembolization is as safe and effective in patients with TIPS as in patients without TIPS, despite worse baseline liver function. Severe adverse events are rare and may be transient.  相似文献   
3.

Purpose

To evaluate the feasibility of a same-day yttrium-90 (90Y) radioembolization protocol with resin microspheres (including pretreatment angiography, lung shunt fraction [LSF] determination, and radioembolization) for the treatment of hepatocellular carcinoma (HCC) and liver metastases.

Materials and Methods

All same-day radioembolization procedures performed over 1 y (February 2017 to January 2018) were included in this single-institutional retrospective analysis, in which 34 procedures were performed in 26 patients (median age, 63 y; 13 women), 19 with liver metastases and 7 with HCC. Yttrium-90 treatment activities were calculated by body surface area method. Tumor imaging response was assessed by Response Evaluation Criteria In Solid Tumors (RECIST) 1.1 for liver metastases and modified RECIST for HCC. Clinical side effects and adverse events were graded per Common Terminology Criteria for Adverse Events version 4.0.

Results

All planned cases were technically successful, and no cases were canceled for elevated LSF or vascular anatomic reasons. Pretreatment angiography modified the planned 90Y treatment activity in 1 case in which vascular anatomy required a lobar-dose split into 2 for segmental infusions. In 18% of cases, patients were briefly admitted after the procedure for observation or symptom management. Imaging evaluation of initial efficacy at 1 month demonstrated partial response in 25% and stable disease in 67% of patients with liver metastases and partial/complete response in 43% and stable disease in 14% of patients with HCC. Grade ≥ 3 adverse events occurred in 6% of cases, with no systemic therapy–limiting toxicities. The mean total procedure time was 4.2 hours.

Conclusions

A same-day 90Y radioembolization protocol with resin microspheres is feasible in select patients, which can expedite cancer therapy.  相似文献   
4.

Objective

Comparative survival between neoadjuvant chemotherapy and adjuvant chemotherapy for patients with cT2-4N0-1M0 non–small cell lung cancer has not been extensively studied.

Methods

Patients with cT2-4N0-1M0 non–small cell lung cancer who received platinum-based chemotherapy were retrospectively identified. Exclusion criteria included stage IV disease, induction radiotherapy, and targeted therapy. The primary end point was disease-free survival. Secondary end points were overall survival, chemotherapy tolerance, and ability of Response Evaluation Criteria In Solid Tumors response to predict survival. Survival was estimated using the Kaplan–Meier method, compared using the log-rank test and Cox proportional hazards models, and stratified using matched pairs after propensity score matching.

Results

In total, 330 patients met the inclusion criteria (n = 92/group after propensity-score matching; median follow-up, 42 months). Five-year disease-free survival was 49% (95% confidence interval, 39-61) for neoadjuvant chemotherapy versus 48% (95% confidence interval, 38-61) for adjuvant chemotherapy (P = .70). On multivariable analysis, disease-free survival was not associated with neoadjuvant chemotherapy or adjuvant chemotherapy (hazard ratio, 1.1; 95% confidence interval, 0.64-1.90; P = .737), nor was overall survival (hazard ratio, 1.21; 95% confidence interval, 0.63-2.30; P = .572). The neoadjuvant chemotherapy group was more likely to receive full doses and cycles of chemotherapy (P = .014/0.005) and had fewer grade 3 or greater toxicities (P = .001). Response Evaluation Criteria In Solid Tumors response to neoadjuvant chemotherapy was associated with disease-free survival (P = .035); 15% of patients receiving neoadjuvant chemotherapy (14/92) had a major pathologic response.

Conclusions

Timing of chemotherapy, before or after surgery, is not associated with an improvement in overall or disease-free survival among patients with cT2-4N0-1M0 non–small cell lung cancer who undergo complete surgical resection.  相似文献   
5.
PurposeTo determine inter-reader agreement in categorizing hepatocellular carcinoma (HCC) treated with locoregional therapy using the Liver Imaging Reporting and Data System (LI-RADS) treatment response (LR-TR) algorithm.Materials and methodsA total of 93 patients with a total of 112 HCC nodules that were treated using thermal ablation or transarterial chemoembolization were prospectively included. There were 79 men and 14 women with a mean age of 55 ± 2.6 (SD) years (range: 48–63 years). All patients underwent magnetic resonance imaging (MRI) examination of the liver and MR images were analyzed by two independent observers. Treated HCC nodules were categorized into four groups according to LR-TR scoring system including: (i) LR-TR non-evaluable (treated, response not evaluable); (ii) LR-TR nonviable (treated, probably or definitively not viable); (iii) LR-TR equivocal (treated, equivocally viable) and (iv) LR-TR viable (treated, probably or definitively viable). The inter-observer agreement in LR-TR categorization was assessed using the kappa statistics.ResultsThere was excellent inter-observer agreement between the two reviewers for overall treated HCC according to LR-TR algorithm (kappa = 0.938; 95% CI: 0.89–1.00; P = 0.001) with 97.31% agreement. The LR-TR categories by both reviewers were non-viable (77/112; 69.6% and 76/112; 67.9%), viable (30/112; 26.8% and 32/112; 27.7%) and equivocal (5/112; 4.4% and 4/112; 3.6%). There was excellent inter-observer agreement for LR-TR nonviable (kappa = 0.938; 95% CI: 0.87–1.0; P = 0.001) with 97.3% agreement, LR-TR viable (kappa = 0.955; 95% CI: 0.89–1.00; P = 0.001) with 98.2% agreement and good inter-observer agreement for LR-TR equivocal (kappa = 0.700; 95% CI: 0.28–1.0; P = 0.001) with 97.3% agreement.ConclusionLR-TR algorithm conveys high degrees of inter-observer agreement for the evaluation of treatment response of HCC after thermal ablation and transarterial chemoembolization.  相似文献   
6.
背景与目的 乳腺肌样错构瘤(MHB)是乳腺错构瘤中极为罕见的亚型,文献中以个案报道为主,目前对其临床与病理学特征认识尚不足,容易漏诊或误诊。为提高对该病的认识,笔者报告1例MHB患者的临床资料,并结合国内学者报告的23例MHB,探讨其组织发生、临床病理特征、临床诊断、治疗及预后。方法 对三峡大学附属仁和医院收治的1例MHB及国内文献报道的23例MHB进行回顾性临床病理分析。结果 患者均为女性,发病年龄19~65岁,平均(37±12.3)岁。24例均为单发性肿瘤,其最大直径范围1.9~10.0 cm,平均(2.9±1.94)cm。笔者报告的1例在全组肿瘤中体积最大(直径10 cm),其占笔者单位20年来受检的1 849例乳腺病理活检标本的0.05%和893例乳腺良性肿瘤的0.1%。影像学检查显示,所有肿瘤均可显示界限清楚的肿块,但图像不具特征性;B超引导下芯针活检有一定诊断价值。肉眼观察显示,均为界限清楚、可活动的无痛性乳腺包块或结节,类似纤维腺瘤。14例(58.3%)有临床诊断记录,但均被误诊为或考虑为乳腺纤维腺瘤。21例(87.5%)行单纯乳腺肿块切除术,3例(12.5%)行乳腺肿块扩大切除术。组织病理学结果显示,肿瘤均由乳腺导管、腺泡和纤维脂肪组织以不同比例随机混合组成;肿瘤内可见特征性平滑肌组织或肌样细胞,分化良好。免疫表型分析显示,肿瘤内平滑肌成分desmin、α-SMA、vimentin、MSA和h-caldesmon呈弥漫性强阳性。20例(83.3%)术后平均随访(18.6±15.4)个月,1例于术后10个月复发,1例于术后36、41个月2次复发,余无复发。结论 MHB是罕见的良性肿瘤,误诊率高。临床医师需增强对MHB的了解和诊断意识。临床和病理诊断中需与乳腺纤维腺瘤等相关肿瘤和瘤样病变鉴别。MHB可复发,治疗应采用广泛局部切除并确保切缘阴性,术后需定期随访。  相似文献   
7.

Background:

The aim of this study was to assess the performance of apparent diffusion coefficient (ADC) measurement obtained with diffusion-weighted magnetic resonance imaging (DW-MRI) to distinguish renal cell carcinomas (RCCs) from small benign solid renal tumors (≤4 cm).

Methods:

In this cross-sectional study, 49 consecutive patients with histopathologically confirmed small solid renal tumors, and seven healthy volunteers were imaged using nonenhanced MRI and DW-MRI. The ADC map was calculated using the b values of 0, 50, 400, and 600 s/mm2 and values compared via the Kruskal–Wallis and Mann–Whitney tests. The utility of ADC for differentiating RCCs and benign lesions was assessed using a receiver operating characteristic curve. Multiple nonenhanced MRI features were analyzed by Logistic regression.

Results:

The tumors consisted of 33 cases of clear-cell RCCs (ccRCCs) and 16 cases of benign tumors, including 14 cases of minimal fat angiomyolipomas and 2 cases of oncocytomas. The ADCs showed significant differences among benign tumors ([0.90 ± 0.52] × 10−3 mm2/s), ccRCCs ([1.53 ± 0.31] × 10−3 mm2/s) and the normal renal parenchyma ([2.22 ± 0.12] × 10−3 mm2/s) (P < 0.001). Moreover, there was statistically significant difference between high and low-grade ccRCCs (P = 0.004). Using a cut-off ADC of 1.36 × 10−3 mm2/s, DW-MRI resulted in an area under the curve (AUC), sensitivity, and specificity equal to 0.839, 75.8%, and 87.5%, respectively. Nonenhanced MRI alone and the combination of imaging methods led to an AUC, sensitivity and specificity equal to 0.919, 93.9%, and 81.2%, 0.998, 97%, and 100%, respectively. The Logistic regression showed that the location of the center of the tumor (inside the contour of the kidney) and appearance of stiff blood vessel were significantly helpful for diagnosing ccRCCs.

Conclusions:

DW-MRI has potential in distinguishing ccRCCs from benign lesions in human small solid renal tumors (≤4 cm), and in increasing the accuracy for diagnosing ccRCCs when combined with nonenhanced MRI.  相似文献   
8.
磷酸甘油酸脱氢酶(phosphoglycerate dehydrogenase,PHGDH)基因编码3-磷酸甘油酸脱氢酶,是糖酵解-丝氨酸生物合成途径中的第一个分支酶.PHGDH氧化糖酵解中间产物3-磷酸甘油酸为磷酸羟基丙酮酸,后通过一系列酶的作用最终合成丝氨酸.丝氨酸在蛋白和细胞增殖所需其他生物分子(如核苷酸、磷脂丝氨酸、鞘氨醇)的合成中起着重要的作用.最新研究发现PHGDH高表达于一系列肿瘤中,且与肿瘤细胞生长、凋亡相关.该文就PHGDH基因结构、功能及与肿瘤的关系作一综述.  相似文献   
9.
环境砷暴露对机体损伤的研究进展   总被引:1,自引:0,他引:1  
砷及其化合物是国际癌症研究机构确认的人类致癌物。砷的广泛分布及其对机体造成许多不良影响,使得砷中毒已然成为全球性公共卫生问题。笔者综述了长期砷暴露引起机体多系统的严重损害,可造成肝脏、肾脏、肺脏、皮肤、神经系统及免疫系统的相关疾病甚至癌症,并对研究长期砷暴露对机体损伤的机制进行了展望。  相似文献   
10.
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