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31.
目的 构建和评价用于预测原发性肝癌(primary liver cancer,PLC)患者射频消融(radiofrequency ablation,RFA) 术后无瘤生存率的列线图模型。 方法 回顾性分析2009年6月至2017年5月于广西医科大学附属肿瘤医院接受射频消融治疗的213例PLC患者的临床资料。PLC患者被随机分为训练组(n=133)和验证组(n=80)。采用Cox回归模型分析射频消融术后复发的因素,并建立复发的列线图模型。通过校准曲线评估模型的预测符合度,Kaplan-Meier 曲线评估模型的实用性,一致性指数(C-index)评估模型的准确度。结果 训练组1年、3年、5年无瘤生存率分别为65.25%、40.91%、26.99%,验证组分别为66.29%、48.10%、24.59%,两组生存曲线比较差异无统计学意义(P=0.785)。Cox回归分析结果显示,肿瘤数目(HR=1.921, 95%CI:1.136~3.251)、丙肝抗体阳性(HR=4.545,95%CI:1.700~12.149)、HBV-DNA≥102 IU/mL(HR=1.993,95%CI:1.209~3.284)及血清前白蛋白(HR=0.996,95%CI:0.993~0.999)为无瘤生存率的影响因素。基于肿瘤数目、HBV-DNA和血清前白蛋白等因素建立列线图模型,训练组和验证组的 C-index 分别为 0.649(95%CI:0.588~0.710)、0.641(95%CI:0.556~0.724),校准图形中标准曲线与预测校准曲线贴合良好。采用列线图将患者分为高风险组和低风险组,高风险组无瘤生存率低于低风险组(P<0.05)。结论 基于肿瘤数目、HBV-DNA和血清前白蛋白等因素建立的列线图测模型可预测PLC射频消融术后的无瘤生存率,对患者辅助治疗具有一定指导价值。  相似文献   
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33.

Objective

Carotid intima–media thickness (IMT) is a noninvasive measurement of early atherosclerosis. Most IMT studies have involved populations with low rates of racial blending. The aim of the present article is to describe IMT value distributions and analyze the influence of sex and race on IMT values in a large Brazilian sample, a setting with a high rate of racial admixture.

Methods

The Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) is a multicenter cohort of 15,105 adult (aged 35–74 years) civil servants in six Brazilian cities. Baseline assessment included IMT measurements in both common carotid arteries. Race was self-reported. We studied the association between sex and race with IMT values using multiple linear regression models. We conducted analyses in all and low-risk individuals, defined as those without classical cardiovascular risk factors.

Results

We analyzed complete IMT data from 10,405 ELSA-Brasil participants. We present nomograms by age for all and low-risk individuals, stratified by sex and race. We found that men had significantly higher maximal IMT values compared with women (β = 0.058; P < 0.001). This association remained for low-risk individuals (β = 0.027; P = 0.001). In addition, Brown and White individuals had lower maximal IMT values compared with Black individuals for all (β = −0.034 and β = −0.054, respectively; P < 0.001) and low-risk individuals (β = −0.027; P = 0.013 and β = −0.035; P < 0.001, respectively).

Conclusion

We found significantly higher IMT values in men. We found significantly higher IMT values in Black individuals than White and Brown individuals. These results persisted when analyses were restricted to low-risk individuals.  相似文献   
34.
BACKGROUND Lung adenocarcinoma(LUAD) is the most common non-small-cell lung cancer, with a high incidence and a poor prognosis.AIM To construct effective predictive models to evaluate the prognosis of LUAD patients.METHODS In this study, we thoroughly mined LUAD genomic data from the Gene Expression Omnibus(GEO)(GSE43458, GSE32863, and GSE27262) and the Cancer Genome Atlas(TCGA) datasets, including 698 LUAD and 172 healthy(or adjacent normal) lung tissue samples. Univariate regression and LASSO ...  相似文献   
35.
Background:The standard of care for breast cancer patients with sentinel lymph node (SLN) metastases includes complete axillary lymph node dissection (ALND). However, many question the need for complete ALND in every patient with detectable SLN metastases, particularly those perceived to have a low risk of non-SLN metastases. Accurate estimates of the likelihood of additional disease in the axilla could assist greatly in decision-making regarding further treatment.Methods:Pathological features of the primary tumor and SLN metastases of 702 patients who underwent complete ALND were assessed with multivariable logistic regression to predict the presence of additional disease in the non-SLNs of these patients. A nomogram was created using pathological size, tumor type and nuclear grade, lymphovascular invasion, multifocality, and estrogen-receptor status of the primary tumor; method of detection of SLN metastases; number of positive SLNs; and number of negative SLNs. The model was subsequently applied prospectively to 373 patients.Results:The nomogram for the retrospective population was accurate and discriminating, with an area under the receiver operating characteristic (ROC) curve of 0.76. When applied to the prospective group, the model accurately predicted likelihood of non-SLN disease (ROC, 0.77).Conclusions:We have developed a user-friendly nomogram that uses information commonly available to the surgeon to easily and accurately calculate the likelihood of having additional, non-SLN metastases for an individual patient.Drs. Manasseh and Bevilacqua contributed equally to the work.Dr. Bevilacqua is currently affiliated with Hospital Sírio Libanes, Instituto Brasileiro de Controle do Câncer, and Disciplina de Cirurgia Geral, Departamento de Cirurgia, Faculdade de Medicina da Univerdidade de Sao Paulo. São Paulo, Brazil; Dr. Boolbol is currently affiliated with Beth Israel Medical Center, New York, New York.  相似文献   
36.
1024例儿童尿流率调查   总被引:2,自引:0,他引:2  
目的 寻求长沙地区儿童尿流率正常值及其列线图。方法 对1024名正常儿童进行1048次尿流率检测。将所得资料按性别、年龄、体表面积、排尿量分组后进行统计学分析,并绘制出各组相应的列线图以阐明尿量、体表面积、平均尿流率、最大尿流率4者的相互关系。结果 正常儿童尿流率曲线为典型的钟形曲线。〈7岁男性儿童的最大尿流率随年龄增加而增加,年龄每增加1岁最大尿流率增加1.7ml/s,〉7岁者其最大尿流率同成年人相仿。〈9岁女性儿童的最大尿流率随年龄增加而增加,年龄每增加1岁最大尿流率增加1.2ml/s,〉9岁其最大尿流率同成年人相近。儿童最大尿流率、平均尿流率及排尿量均随体表面积增加而增加,同时,最大尿流率、平均尿流率也均随排尿量的增加而增加。结论 〈9岁的女童和〈7岁的男童最大尿流率的正常值有明显的年龄依从性。  相似文献   
37.

Purpose

To assess adherence rates to pelvic lymph node dissection (PLND) according to National Comprehensive Cancer Network (NCCN) PLND guideline (2% or higher risk) and D’Amico lymph node invasion (LNI) risk stratification (intermediate/high risk) in contemporary North American patients with prostate cancer treated with radical prostatectomy (RP).

Material and methods

We relied on 49,358 patients treated with RP and PLND (2010–2013) in SEER database. Adherence rates were quantified and multivariable (MVA) logistic regression analyses tested for independent predictors.

Results

According to NCCN PLND guideline and D’Amico LNI classification, PLND was recommended in 63.3% and 64.9% of patients, respectively. Corresponding adherence rates were 68.8% and 69.1%. Adherence rates improved from 67.3% to 71.6% and from 67.6% to 72.0%, respectively, over time. In MVA, more advanced clinical stage, higher biopsy Gleason score and higher number of positive biopsy cores predicted PLNDs that were performed below NCCN LNI nomogram risk threshold. Conversely, lower clinical stage, lower PSA and lower biopsy Gleason score predicted PLND omission in individuals with risk level above NCCN LNI nomogram risk threshold. MVA results for D’Amico classification were virtually identical.

Conclusions

Adherence to NCCN PLND guideline and D’Amico LNI classification for purpose of PLND is suboptimal in SEER population-based patients treated with RP. However, adherence rates have improved over time. Patients, who did not undergo PLND despite elevated LNI risk, had more favorable PCa characteristics than the average. Conversely, patients, who underwent PLND despite low-risk, had worse PCa characteristics than the average.  相似文献   
38.
39.
Background  Lymph node involvement is a very important prognostic factor for cutaneous melanoma. In this paper we try to validate a nomogram that was created at the Memorial Sloan–Kettering Cancer Center, New York, to predict the probability of metastases in the sentinel nodes of patients with cutaneous melanoma. Methods  Values of the following variables were collected in 218 patients with cutaneous melanoma and sentinel lymph node: age, thickness, level of Clark, location of the lesion, and ulceration or not, and the nomogram was applied to assess the probability of sentinel node involvement in each patient. The discrimination of the nomogram was assessed by calculating the area under the receiver operating characteristics (ROC) curve, and to assess the accuracy of the nomogram actual probabilities were plotted against the nomogram-calculated predicted probability. Results  The overall predictive accuracy of the nomogram was 0.869 (95% confidence interval 0.813–0.925). Mean predicted probability of sentinel node metastasis was highly correlated to the observed risk (r = 0.953; P < 0.012). Conclusion  The nomogram is a useful diagnostic tool that provides an adequate accurate prediction of the probability of sentinel lymph node metastases in patients with cutaneous melanoma.  相似文献   
40.
Background  A Breast Cancer Nomogram (BCN) for predicting nonsentinel lymph node (NSLN) involvement has been developed and prospectively tested in several series. However, its clinical applicability has never been tested among surgeons. Methods  The BCN was applied to 209 SLN-positive patients. Its performance was assessed by the area under the receiver–operating characteristic (ROC) curve. Surgeons in Quebec were surveyed to determine the predicted NSLN positivity below which they would not dissect the axilla. The accuracy of the BCN was determined in this clinically relevant range. Results  The predictive accuracy of the BCN had an area under the ROC curve of 0.687. Almost half of interviewed surgeons treat over 20 breast cancer per year. Fourteen out of 82 surgeons questioned would never leave the patient without a completion axillary dissection after a positive SLN, regardless of the BCN result. Seventy one percent of them would not complete axillary dissection if the prediction of a positive NSLN was ≤10%. Only 37 of the 209 patients were in this 10% or less category, with a mean observed rate of positive NSLN of 13% (95% confidence interval [CI], 2–24%). Conclusion  The global performance of the BCN was fair. A majority of surgeons in Quebec would omit an axillary lymph node dissection (ALND) if the predicted probability of positive NSLN is 10% or less. Although useful, the BCN data should be used with caution at the low end of the scale. Because of some limitations in the performance in this category, other clinical factors and judgment must accompany its use.  相似文献   
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