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Background

Given the lack of established indications for elective nodal irradiation (ENI) in ypN0 patients after neoadjuvant chemotherapy (NAC) and breast-conserving surgery (BCS), we set out to investigate the role of ENI in ypN0 patients according to subtype and pathologic complete remission (pCR) status.

Patients and Methods

We analyzed 261 patients who received NAC followed by BCS and adjuvant radiotherapy in 13 institutions of the Korean Radiation Oncology Group from 2005 to 2011. The tumors were classified into one of 3 subtypes: luminal (estrogen receptor positive or progesterone receptor positive and HER2 negative), HER2 (HER2 positive), or triple negative (estrogen receptor, progesterone receptor, and HER2 negative). We compared locoregional control (LRC), disease-free survival (DFS), and overall survival (OS) according to ENI in different subgroups generated by the subtype and pCR statuses.

Results

In all patients, the 5-year LRC, DFS, and OS rates were 96.0%, 91.0%, and 96.8%, respectively. In all patients, axillary lymph node dissection was found to be the only favorable factor for LRC (P = .023) and DFS (P = .001). Age ≥ 50 years (P = .027), negative resection margin (P = .002), and axillary lymph node dissection (P = .002) were all favorable factors for OS. ENI did not affect LRC, DFS, or OS. Subgroup analysis by tumor subtype and pCR showed that ENI was not associated with greater LRC or DFS in any subgroups.

Conclusion

In ypN0 patients after NAC and BCS, ENI did not improve LRC or survival, regardless of subtype or primary tumor response. This result should be verified through larger prospective trials.  相似文献   
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Objective: A systematic review reported that coffee consumption would decrease risk of colon cancer in Asian women. But the systematic review arises the issue of duplication, so that a meta-epidemiological study was conducted. Methods: The selection criteria were defined that a prospective cohort follow-up study conducted to evaluate coffee consumption and risk of colon cancer in Asian and showed adjusted relative risk and its 95% confidence interval. In order to conduct meta-analysis, the highest versus lowest method was applied to extract relative risk and its 95% confidence intervals of the highest category. Random effect model was applied if I-squared value was over 50%. Results: After avoiding duplication, 9 cohort data were selected for meta-analysis. The summary relative risk (and their 95% confidence intervals) [I-square value] were 0.90 (95% CI: 0.79-1.03) [0.0%] in men, and 0.64 (95% CI: 0.36-1.15) [65.9%] in women, respectively. Conclusions: The results suggest that coffee consumption is not associated with the risk of colon cancer in Asian men and women. The findings of this study are consistent with the results of two systematic reviews conducted under the same hypothesis and selection criteria. Additional epidemiological studies are needed for the inflection of colon cancer risk as the dose of coffee increases and the difference in the protective effect by sex.  相似文献   
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Objective: While it has been claimed that lung cancer occurs due to epigenetic mechanisms, four systematic reviews were reported to investigate the association between serum folate levels and lung cancer risk. Considering some methodological problems founded in the systematic review, a meta-epidemiological study was conducted. Methods: The selection criteria of this study were defined that a case-control study was conducted to determine the risk of lung cancer occurrence according to the concentration of serum folate and its results showed odds ratio and its 95% confidence interval. Additional paper was explored from cited lists of 4 papers selected by previous systematic reviews. Random effect model was applied if I-squared value was over 50%. Results: For 5 case-control studies selected, the summary odds ratios (and their 95% confidence intervals) were 0.82 (0.74-0.90) in men, 0.70 (0.62-0.79) in former smokers, and 0.86 (0.75-1.00) in non-smokers. Conclusion: Higher foliate levels can decrease lung cancer risk in men and former smokers. Especially, the protective effect was highest in former smokers compared in non-smokers and current smokers. Based on these facts, folate fortification programs to reduce lung cancer risk would be focused on former smokers in men. And some epidemiological studies are needed to provide a hypothesis to explain the sex differences in the association between folate and lung cancer risk.  相似文献   
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The topography of the facial muscles differs between males and females and among individuals of the same gender. To explain the unique expressions that people can make, it is important to define the shapes of the muscle, their associations with the skin, and their relative functions. Three‐dimensional (3D) motion‐capture analysis, often used to study facial expression, was used in this study to identify characteristic skin movements in males and females when they made six representative basic expressions. The movements of 44 reflective markers (RMs) positioned on anatomical landmarks were measured. Their mean displacement was large in males [ranging from 14.31 mm (fear) to 41.15 mm (anger)], and 3.35–4.76 mm smaller in females [ranging from 9.55 mm (fear) to 37.80 mm (anger)]. The percentages of RMs involved in the ten highest mean maximum displacement values in making at least one expression were 47.6% in males and 61.9% in females. The movements of the RMs were larger in males than females but were more limited. Expanding our understanding of facial expression requires morphological studies of facial muscles and studies of related complex functionality. Conducting these together with quantitative analyses, as in the present study, will yield data valuable for medicine, dentistry, and engineering, for example, for surgical operations on facial regions, software for predicting changes in facial features and expressions after corrective surgery, and the development of face‐mimicking robots. Clin. Anat. 28:735–744, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
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