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991.
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Interval breast cancers (those diagnosed between recommended mammography screens) generally have poorer outcomes and are more common among women with dense breasts. We aimed to develop a risk model for interval breast cancer. We conducted a nested case–control study within the Melbourne Collaborative Cohort Study involving 168 interval breast cancer patients and 498 matched control subjects. We measured breast density using the CUMULUS software. We recorded first-degree family history by questionnaire, measured body mass index (BMI) and calculated age-adjusted breast tissue aging, a novel measure of exposure to estrogen and progesterone based on the Pike model. We fitted conditional logistic regression to estimate odds ratio (OR) or odds ratio per adjusted standard deviation (OPERA) and calculated the area under the receiver operating characteristic curve (AUC). The stronger risk associations were for unadjusted percent breast density (OPERA = 1.99; AUC = 0.66), more so after adjusting for age and BMI (OPERA = 2.26; AUC = 0.70), and for family history (OR = 2.70; AUC = 0.56). When the latter two factors and their multiplicative interactions with age-adjusted breast tissue aging (p = 0.01 and 0.02, respectively) were fitted, the AUC was 0.73 (95% CI 0.69–0.77), equivalent to a ninefold interquartile risk ratio. In summary, compared with using dense breasts alone, risk discrimination for interval breast cancers could be doubled by instead using breast density, BMI, family history and hormonal exposure. This would also give women with dense breasts, and their physicians, more information about the major consequence of having dense breasts—an increased risk of developing an interval breast cancer.  相似文献   
993.
Advanced melanoma patients who failed anti-PD-1 therapy have limited options. We analyzed a cohort of 133 advanced melanoma patients receiving anti-PD-1 monotherapy in a referral center between April 2015 and December 2017, and included the 26 patients with confirmed progressive (PD) or stable disease who received additional radiotherapy with an unmodified anti-PD-1 mAb regimen. Tumor evaluations were done on radiated and nonradiated (RECIST 1.1) lesions, with abscopal effect defined as a partial (PR) or complete response (CR) outside radiated fields. Primary endpoint was the CR + PR rate in radiated + nonradiated lesions. Secondary endpoints were progression-free survival (PFS), melanoma-specific survival (MSS) and safety. First late radiotherapy, consisting of hypofractionated radiotherapy (3–5 sessions, 20–26 Gy), standard palliative radiotherapy or brain radiosurgery was begun after a median of 6.3 months of anti-PD-1 in 23, 2 and 1 patient(s), respectively. Best response was 8 (31%) CR, 2 (8%) profound PR allowing surgical resection of remaining metastases and 16 (62%) PD. Abscopal effect was seen in 35% of patients. Median PFS and MSS since anti-PD-1 initiation was 15.2 [95% CI: 8.0 not achieved (na)] and 35.3 [95% CI: 18.5 na] months, respectively. PFS curves seemed to achieve a plateau. We discontinued anti-PD-1 therapy in 9/10 of patients with no residual evaluable disease and observed one relapse after a median of 10 months off anti-PD1-therapy. No unusual adverse event was recorded. Limitations of the study include its retrospective nature and limited size. Hypofractionated radiotherapy may enhance anti-PD1 monotherapy efficacy in patients who previously failed anti-PD-1 therapy. Controlled studies are needed.  相似文献   
994.
Adiposity increases estrogen receptor (ER)-positive postmenopausal breast cancer risk. While mechanisms underlying this relationship are uncertain, dysregulated sex-steroid hormone production and insulin signaling are likely pathways. Our aim was to quantify mediating effects of fasting insulin and free estradiol in the adiposity and ER-positive postmenopausal breast cancer association. We used data from a case–cohort study of sex hormones and insulin signaling nested within the Melbourne Collaborative Cohort Study. Eligible women, at baseline, were not diagnosed with cancer, were postmenopausal, did not use hormone therapy and had no history of diabetes or diabetes medication use. Women with ER-negative disease or breast cancer diagnosis within the first follow-up year were excluded. We analyzed the study as a cumulative sampling case–control study with 149 cases and 1,029 controls. Missing values for insulin and free estradiol were multiply imputed with chained equations. Interventional direct (IDE) and indirect (IIE) effects were estimated using regression-based multiple-mediator approach. For women with body mass index (BMI) >30 kg/m2 compared to women with BMI 18.5–25 kg/m2, the risk ratio (RR) of breast cancer was 1.75 (95% confidence interval [CI] 1.05–2.91). The estimated IDE (RR) not through the mediators was 1.03 (95% CI 0.43–2.48). Percentage mediated effect through free estradiol was 72% (IIE-RR 1.56; 95% CI 1.11–2.19). There was no evidence for an indirect effect through insulin (IIE-RR 1.12; 95% CI 0.68–1.84; 28% mediated). Our results suggest that circulating free estradiol plays an important mediating role in the adiposity–breast cancer relationship but does not explain all of the association.  相似文献   
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996.
Objective: This study investigated the association between fruit and vegetable intake and stomach cancer, with considering the impacts of Helicobacter pylori (H. pylori) infection and tobacco smoking. Methods: A case-control study featuring 80 male incident stomach-cancer cases and 126 male controls was conducted in a general hospital in Viet Nam. A semi-quantitative food frequency and demographic lifestyle questionnaire were used; and venous blood samples were collected to determine H. pylori status by IgG ELISA. The respective associations between fruit and vegetable intake and stomach cancer were examined using unconditional logistic regression analysis with adjustments for possible cofactors. Results: Fruit intake and stomach cancer showed a weak inverse association when this became non-significant after adjusting for H. pylori infection (OR = 0.50, 95%CI: 0.22–1.12, p trend = 0.094). Stratifying by H. pylori status returned a negative trend for fruit intake and stomach cancer among H. pylori-negative participants (OR = 0.21, 95%CI: 0.06–0.69, p trend = 0.010), but no significant interaction for H. pylori-positive participants (OR = 0.76, 95%CI: 0.21–2.68, p trend = 0.670). Vegetable intake and stomach cancer showed no association, regardless of H. pylori status. Compared to ever-smokers with low intake, never-smokers with high vegetable (OR = 0.25, 95% CI: 0.06–0.95) and fruit intake (OR = 0.20, 95%CI: 0.06–0.65) showed the lowest odds of stomach cancer. Conclusions: Fruit, but not vegetable, intake showed a weak inverse association with stomach cancer. H. pylori infection and tobacco-smoking status may influence the protective effects of fruit and vegetable intake on stomach cancer.  相似文献   
997.
BACKGROUND & AIMS: Increased intrahepatic resistance in cirrhosis is associated with reduced endothelial NO synthase (eNOS) activity and exacerbated by superimposed inflammation. NOSTRIN induces intracellular translocation of eNOS and reduces NO generation. Our aims were to quantify and compare hepatic expression of eNOS, NOSTRIN, NOSIP, and caveolin-1 in alcoholic cirrhosis with or without superimposed alcoholic hepatitis and in normal livers. METHODS: Biopsy specimens from 20 decompensated alcoholic cirrhotic patients with portal hypertension (10 with alcoholic hepatitis) and 6 normal livers were analyzed: real-time polymerase chain reaction for quantification of messenger RNA; Western blotting; and enzyme assays of eNOS in normal and diseased liver were performed. Localization and interaction of eNOS and NOSTRIN in liver was assessed by immunohistochemistry and co-immunoprecipitation. RESULTS: eNOS mRNA was significantly increased and eNOS activity decreased in alcoholic hepatitis patients, despite no differences in eNOS protein expression among the patients. Patients with alcoholic hepatitis had significantly higher hepatic levels of NOSTRIN and caveolin-1 mRNA compared with cirrhosis alone or normal biopsy specimens. A NOSTRIN splice variant, not present in normal tissue, was detected on mRNA and protein levels in all alcoholic patients. Coimmunoprecipitation demonstrated association among NOSTRIN, eNOS, and caveolin-1. CONCLUSIONS: An increase in mRNA and protein of NOSTRIN and its shortened variant in alcoholic hepatitis may partly account for the paradox of increased mRNA levels and normal protein expression but decreased enzymatic activity of eNOS in diseased liver. Such intracellular regulators of NO production may be important in the development of increased intrahepatic resistance in alcoholic hepatitis patients.  相似文献   
998.
The optimal reperfusion strategy in elderly patients with ST-segment elevation myocardial infarction (STEMI) remains a topic of debate. Therefore, we investigated in the MITRA PLUS registry clinical outcome variables in 5455 patients aged>70 years and STEMI on admission at hospitals without the facilities of coronary catheterization and PCI. Outcome was compared after thrombolysis, transfer to PCI and after no reperfusion therapy. Data of this registry in STEMI patients older than 70 years, who were transferred to another hospital for PCI, showed a strong trend for lower in-hospital mortality rates compared with a strategy with sole fibrinolysis and significantly lower in hospital death rates compared with a conservative treatment without (medical or mechanical) reperfusion. Additionally, the PCI group also had a reduced incidence of the combined events: death, myocardial reinfarction, stroke in comparison with both other infarct groups. Data of the presented MITRA PLUS registry in STEMI patients older than 70 years support data of several other studies, that patients with STEMI benefit from a transfer to primary PCI even after a time delay of symptom onset to hospital admission of more than 2 h compared with a strategy using sole fibrinolytic therapy.  相似文献   
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