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Journal of Neuro-Oncology - There is growing evidence that the subventricular zone (SVZ) plays a key role in glioblastoma (GBM) tumorigenesis. However, little is known regarding how the SVZ, which...  相似文献   
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Objectives

To examine the potential added value of a simple 5-item questionnaire for sarcopenia screening (SARC-F) to the Fracture Risk Assessment Tool (FRAX) for hip fracture risk prediction, in order to identify at-risk older adults for screening with dual-energy x-ray absorptiometry (DXA).

Design

A prospective cohort study.

Setting and participants

Two thousand Chinese men and 2000 Chinese women aged 65 years or older were recruited from local communities and were prospectively followed up for about 10 years.

Measures

Areal bone mineral density (BMD) of hip and lumbar spine were measured by DXA at baseline. Ten-year FRAX probability of hip fracture was calculated using the baseline risk factors. Information from the baseline questionnaire was extracted to calculate a modified SARC-F score. The independent predictive values of SARC-F and FRAX questionnaire were evaluated using multivariate survival analysis. The added predictive values of SARC-F to FRAX for pre-DXA screening were examined.

Results

During the follow-up, 63 (3.2%) men and 69 (3.5%) women had at least 1 incident hip fracture. SARC-F had an independent value of FRAX for hip fracture risk prediction, with an adjusted hazard ratio [95% confidence interval (CI)] of 1.24 (1.02, 1.52) and 1.15 (0.99, 1.13) in men and women, respectively. Compared with using FRAX, using SARC-F in conjunction with FRAX made the sensitivity for prediction rise from 58.7% to 76.2% in men and from 69.6% to 78.3% in women, with a nondecreased area under receiver operating characteristic curve of 0.67. Prescreening using FRAX in conjunction with SARC-F could save more than half of the DXA assessment than with no prescreening.

Conclusions/Implications

SARC-F is associated with a modest increase in hip fracture risk, especially in men. Conjoint evaluation for sarcopenia in addition to FRAX screening may help identify older adults at higher risk of hip fracture for more intensive screening and/or preventive interventions.  相似文献   
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Journal of Neuro-Oncology - Gliomas are among the most common primary brain malignancies, with a poor prognosis for high grade gliomas despite aggressive therapy. Carbon ions, which exhibit...  相似文献   
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Purpose

A hydrogel rectal spacer (HRS) is a medical device that is approved by the U.S. Food and Drug Administration to increase the separation between the prostate and rectum. We conducted a cost-effectiveness analysis of HRS use for reduction in radiation therapy (RT) toxicities in patients with prostate cancer (PC) undergoing external beam RT (EBRT).

Methods and Materials

A multistate Markov model was constructed from the U.S. payer perspective to examine the cost-effectiveness of HRS in men with localized PC receiving EBRT (EBRT alone vs EBRT + HRS). The subgroups analyzed included site of HRS placement (hospital outpatient, physician office, ambulatory surgery center) and proportion of patients with good baseline erectile function (EF). Data on EF, gastrointestinal and genitourinary toxicities incidence, and potential risks associated with HRS implantation were obtained from a recently published randomized clinical trial. Health utilities and costs were derived from the literature and the 2018 Physician Fee Schedule and were discounted 3% annually. Quality-adjusted life years (QALYs) and costs were modeled for a 5-year period from receipt of RT. Probabilistic sensitivity analysis and value-based threshold analyses were conducted.

Results

The per-patient 5-year incremental cost for spacers administered in a hospital outpatient setting was $3578, and the incremental effectiveness was 0.0371 QALYs. The incremental cost-effectiveness ratio was $96,440/QALY for patients with PC undergoing HRS insertion in a hospital and $39,286/QALY for patients undergoing HRS insertion in an ambulatory facility. For men with good baseline EF, the incremental cost-effectiveness ratio was $35,548/QALY and $9627/QALY in hospital outpatient and ambulatory facility settings, respectively.

Conclusions

Based on the current Medicare Physician Fee Schedule, HRS is cost-effective at a willingness to pay threshold of $100,000. These results contain substantial uncertainty, suggesting more evidence is needed to refine future decision-making.  相似文献   
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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   
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