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1.

Purpose

The purpose of this study was to evaluate trends in demographics and outcomes of pediatric breast cancer in a United States population-based cohort.

Methods

The Surveillance, Epidemiology, and End Results (SEER) database was utilized to identify all pediatric patients with malignant breast tumors between 1973 and 2014. Analysis was performed using Stata Statistical Software version 13.1. Associations between categorical variables were made using X2 test. Log-rank test was used for univariate survival analysis. Kaplan–Meier analysis investigated five-year survival rates across several variables. Adjusted analysis was performed using a Cox Proportional-Hazards regression.

Results

134 patients with breast malignancies were identified. Carcinoma was the most prevalent histology (48.5%), followed by fibroepithelial tumors (FETs) (35.1%), and sarcoma (14.2%). FETs were twice as common in black compared to nonblack patients (56.3% vs. 29.0%, p?<?0.01). Analyzing histology by stage revealed that 100% of FETs were early stage disease (p?<?0.0001). 46.7% of the tumors tested were ER/PR negative, more than twice as many compared to the published adult estimate of 20.0%. Unadjusted survival analysis revealed worse survival for patients with adenocarcinoma/sarcomas, advanced stage, and high grade disease, without a survival difference between races.

Conclusion

Breast cancer remains a rare malignancy among pediatric patients. Although black patients were found to have more noncarcinomatous tumors with less advanced disease, this did not confer a survival advantage.

Type of study

Retrospective cohort study.

Level of evidence

Level III.  相似文献   
2.
Metabolomics may reveal novel insights into the etiology of prostate cancer, for which few risk factors are established. We investigated the association between patterns in baseline plasma metabolite profile and subsequent prostate cancer risk, using data from 3,057 matched case–control sets from the European Prospective Investigation into Cancer and Nutrition (EPIC). We measured 119 metabolite concentrations in plasma samples, collected on average 9.4 years before diagnosis, by mass spectrometry (AbsoluteIDQ p180 Kit, Biocrates Life Sciences AG). Metabolite patterns were identified using treelet transform, a statistical method for identification of groups of correlated metabolites. Associations of metabolite patterns with prostate cancer risk (OR1SD) were estimated by conditional logistic regression. Supplementary analyses were conducted for metabolite patterns derived using principal component analysis and for individual metabolites. Men with metabolite profiles characterized by higher concentrations of either phosphatidylcholines or hydroxysphingomyelins (OR1SD = 0.77, 95% confidence interval 0.66–0.89), acylcarnitines C18:1 and C18:2, glutamate, ornithine and taurine (OR1SD = 0.72, 0.57–0.90), or lysophosphatidylcholines (OR1SD = 0.81, 0.69–0.95) had lower risk of advanced stage prostate cancer at diagnosis, with no evidence of heterogeneity by follow-up time. Similar associations were observed for the two former patterns with aggressive disease risk (the more aggressive subset of advanced stage), while the latter pattern was inversely related to risk of prostate cancer death (OR1SD = 0.77, 0.61–0.96). No associations were observed for prostate cancer overall or less aggressive tumor subtypes. In conclusion, metabolite patterns may be related to lower risk of more aggressive prostate tumors and prostate cancer death, and might be relevant to etiology of advanced stage prostate cancer.  相似文献   
3.
4.
A diary method using household measures was employed to obtain dietary records in a large national prospective survey and a computer program, DIDO (Diet In Data Out), was designed for direct entry of the diaries. The accuracy of this computerized coding system was examined alongside that of the manual coding used for a similar diary in a previous wave, 7 years earlier, of the same survey. Accuracy was assessed by analysis of the errors in the coded and checked records by stringent re-checking of nominal 2% random subsamples of the diet diaries coded by each method. The mean time to code and check each of the 2086 7-day records in the whole survey using DIDO was 58 minutes (SD 30) compared with reported results of 1–4 hours for manual methods. The mean error rate of computerized coding and checking with DIDO was 2.3% (SD 2.1; range 0–8.9) per diary in the subsample. Correcting these mistakes made insignificant changes to the calculated mean energy and nutrient intakes for the subsample. The percentage of individuals changing to an adjacent third of nutrient distribution after correcting unambiguous errors ranged from none (for alcohol) to 11% (for carbohydrate and calcium intake). The mean error rate on a similar subsample of diaries from the earlier survey which had been coded manually was significantly higher at 5.9% (SD 4.1; range 0–17) per diary. Emphasis is laid on the importance, in coding, of dealing with ambiguities in the subjects' records, since this can affect the accuracy and the precision of the nutrient results obtained. We conclude that the DIDO coding method has the advantages of greater accuracy, speed, consistency and efficient data handling, and affords greater data accessibility for checking, compared with manual systems.  相似文献   
5.
用3H-甘露糖标记7721人肝癌细胞表面糖蛋白的N-糖链,经提取和去唾液酸后,用ConA和DSA亲和柱顺序层析将3H-标记的N-糖链分成4个类型和天线数不同的组分来研究维甲酸(RA)对细胞表面N-糖链的影响。结果:10μmol/LRA处理细胞3~5d后,可使C2C2二天线复杂型N-糖链增加,而高甘露糖型及三、四天线,特别是带有C2,6分支结构的复杂型H-糖链减少。用LCA亲和柱还证明二天线糖链中的核心岩藻糖也减少。进一步发现上述改变的酶学机制是RA降低N-乙酰氨基萄葡糖转移酶V和α-1,6-核心岩藻糖转移酶的活力。结论:BA通过改变某些糖基转移酶活力而改变细胞表面糖链结构,这可能是RA使7721细胞诱导分化的机理之-。  相似文献   
6.
Although the conventional outside-in technique is especially useful for repairing tears in the anterior portion of the meniscus, it has a disadvantage of making an additional 1–2 cm sized skin incision and tying knots subcutaneously over the capsule. Therefore we devised two all-inside repair techniques of lateral meniscus anterior horn tear according to the site of meniscal tear, meniscosynovial junction or red–red zone. Because these techniques are modified methods of the outside-in meniscal repair using a spinal needle, they are as simple as conventional outside-in technique. In addition they have advantages of vertical mattress suture, which is an important characteristic of the all-inside repair, and no additional incision. We recommend these techniques as an alternative method for repairing an anterior horn tear of the lateral meniscus.  相似文献   
7.
The authors conducted a complete audit of results of 38,633 mammographic examinations performed by 12 general radiologists during a 2-year period with a computerized reporting system. During this period, 11 group members attended 17 dedicated mammography courses. Audit results were analyzed for each radiologist and the entire group. In the 2nd year, the number of breast cancers diagnosed increased 50% (from 121 to 181), with a 6.5% increase in patient volume. Sensitivity increased from 80% to 87%, and there was no change in the positive predictive value of 32%. Median tumor size and node positivity decreased. Most major variables of population and technical factors were unchanged. Diagnostic approach was altered during the 2nd year, as shown by a 50% increase in the use of spot compression, magnification views, and sonography. Analysis of each radiologist's performance before and after attending mammography courses showed similar changes. These data suggest that dedicated mammography courses can help improve radiologists' performance and alter their interpretive approach.  相似文献   
8.
We report a case of seminoma associated with crossed fused renal ectopia and a duplicated vena cava. The impact of these congenital anomalies on the treatment of testicular seminoma is discussed.  相似文献   
9.
BACKGROUND: Chlorofluorocarbon (CFC)-free metered-dose inhalers (MDIs) were introduced into Australia in 1999. Device care instructions were modified (e.g., CFC-free salbutamol inhalers to be washed weekly), but this information was not communicated directly to health care professionals. OBJECTIVE: This pilot study aimed to assess the level of awareness of device care protocols for CFC-free MDIs by patients and their pharmacists. SETTING AND DESIGN: Purchasers of CFC-free MDIs were recruited from four community pharmacies. They were interviewed regarding information sources, knowledge of propellant change, and awareness of and adherence to device care protocols. The dispensing pharmacists were interviewed for knowledge of CFC-free device care. The primary outcome variable was awareness of the relevant device care protocol. RESULTS: Thirty-nine patients were interviewed. Most patients (77%) were aware of the change to CFC-free propellant. Only nine patients (23%) were aware of the need to wash the device holder, and four patients (10% of total) complied with the specified protocol. One of the ten dispensing pharmacists could describe correct device care protocols for the CFC-free MDIs. CONCLUSIONS: Although most patients are aware that MDIs are now CFC-free, there is a low level of awareness of the device care required for these inhalers, and a very low rate of compliance with recommended practice. Although the clinical impact of failing to wash the device holder is unclear, this added instruction may have substantial implications for patient satisfaction and medication delivery. Pharmaceutical manufacturers need to highlight to health care professionals any clinically important changes in device care instructions, so that appropriate information may be passed on to patients.  相似文献   
10.
目的:探讨计算机图像分析技术对乳腺肿瘤核仁组成区相关嗜银蛋白(AgNORs)表达在病理学诊断中的意义。方法:选取乳癌、乳腺结构不良、乳腺纤维腺瘤及正常乳腺组织各20例,应用图像分析系统和嗜银染色技术,对乳腺病变组织的AgNORs进行形态计量学分析,观察每个细胞的胞核面积、核周长以及AgNOR颗粒数目、颗粒面积、AgNOR的大颗粒数、形态因子、面积比值、平均面积等8项参数。结果:正常乳腺及乳腺结构不良、乳腺纤维腺瘤组织的细胞核面积、核周长以及AgNOR颗粒数目、颗粒面积明显小于乳癌组织(P<0.01),AgNOR的大颗粒数、形态因子、面积比值、平均面积在乳癌组织与乳腺纤维腺瘤及正常乳腺组织间差异有统计学意义(P<0.05)。上述8项参数4组间多类判别分析回代符合率为72.5%,癌和非癌的判别回代符合率达100%。结论:图像分析对于乳腺良、恶性病变的鉴别诊断具有重要价值,是一精确、客观的AgNOR定量研究手段。  相似文献   
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