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81.

BACKGROUND:

This multicenter study aimed to identify prognostic factors in patients with brain metastases from malignant melanoma (BM‐MM).

METHODS:

In a retrospective survey in 9 cancer centers of the German Cancer Society, 692 patients were identified with BM‐MM during the period 1986 through 2007. Overall survival was analyzed using a Kaplan‐Meier estimator and compared with log‐rank analysis. Cox proportional hazards models were used to identify prognostic factors significant for survival.

RESULTS:

The median overall survival of the entire cohort was 5.0 months (95% confidence interval [95% CI], 4 months‐5 months). Significant prognostic factors in the univariate Kaplan‐Meier analysis were Karnofsky performance status (≥70% vs <70%; P < .001), number of BM‐MM (single vs multiple; P < .001), pretreatment levels of lactate dehydrogenase (LDH) (normal vs elevated; P < .001) and S‐100 (normal vs elevated; P < .001), prognostic groups according to Radiation Therapy Oncology Group (class I vs class II vs class III; P = .0485), and treatment choice (for the cohort with single BM‐MM only) (stereotactic radiotherapy or neurosurgical metastasectomy vs others; P = .036). Cox proportional hazards models revealed pretreatment elevated level of serum LDH (hazard ratio [HR], 1.6; 95% CI, 1.3‐2.0 [P = .00013]) and number of BM‐MM (HR, 1.6; 95% CI, 1.3‐2.0 [P = .00011]) to be independent prognostic variables in the entire cohort, whereas in patients with a single BM‐MM, treatment choice (HR, 1.5; 95% CI, 1.1‐1.9 [P = .0061]) was identified as a unique prognostic factor.

CONCLUSIONS:

The overall survival of patients with BM‐MM primarily depends on the number of metastases and pretreatment level of LDH. In the case of a single brain metastasis, stereotactic radiotherapy or neurosurgical metastasectomy is by far the most important factor for improving survival. Cancer 2011. © 2010 American Cancer Society.  相似文献   
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Residual tumor cells remain beyond the margins of every glioblastoma (GBM) resection. Their resistance to postsurgical therapy is considered a major driving force of mortality, but their biology remains largely uncharacterized. In this study, residual tumor cells were derived via experimental biopsy of the resection margin after standard neurosurgery for direct comparison with samples from the routinely resected tumor tissue. In vitro analysis of proliferation, invasion, stem cell qualities, GBM‐typical antigens, genotypes, and in vitro drug and irradiation challenge studies revealed these cells as unique entities. Our findings suggest a need for characterization of residual tumor cells to optimize diagnosis and treatment of GBM. ANN NEUROL 2010;68:264–269  相似文献   
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The aim of secondary prevention of skin cancer is to diagnose neoplasia at early non-invasive growth phases which are not associated with the risk of metastasis. Secondary prevention is achieved by screening programs which allow identification of patients at high risk for skin cancer and by improvement of diagnostic accuracy. This can be partially achieved by the application of dermoscopy which improves the diagnostic accuracy by more than 35%. A consistent treatment of precursor lesions, such as solar keratoses or Bowen??s disease can reduce the rate of squamous cell carcinoma especially in patients at risk. An early diagnosis of recurrent disease in skin cancer patients can be achieved by a standardized risk profile adapted follow-up.  相似文献   
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The authors evaluated the association of complexity of work with data, people, and things with the incidence of dementia, Alzheimer's disease, and vascular dementia in the Canadian Study of Health and Aging, while adjusting for work-related physical activity. The Canadian Study of Health and Aging is a 10-year population study, from 1991 to 2001, of a representative sample of persons aged 65 years or older. Lifetime job history allowed application of complexity scores and classification of work-related physical activity. Analyses included 3,557 subjects, of whom 400 were incident dementia cases, including 299 with Alzheimer's disease and 93 with vascular dementia. In fully adjusted Cox regression models, high complexity of work with people or things reduced risk of dementia (hazard ratios were 0.66 (95% confidence interval: 0.44, 0.98) and 0.72 (95% confidence interval: 0.52, 0.99), respectively) but not Alzheimer's disease. For vascular dementia, hazard ratios were 0.36 (95% confidence interval: 0.15, 0.90) for high complexity of work with people and 0.50 (95% confidence interval: 0.25, 1.00) for high complexity of work with things. Subgroup analyses according to median duration (23 years) of principal occupation showed that associations with complexity varied according to duration of employment. High complexity of work appears to be associated with risk of dementia, but effects may vary according to subtype.  相似文献   
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In 2015, the Patient Protection and Affordable Care Act of 2010 will mandate reduced Medicare reimbursements for hospitals with Chronic Obstructive Pulmonary Disease (COPD) readmissions that are higher than expected. Several studies identified social issues as a concern and possible contributor to readmissions. This study calculated readmission rates for patients with COPD following an enhanced psychosocial assessment. With 26 participants serving as their own historical controls, a paired t-test of the mean of admissions 90 days prior to the assessment and 90 days postassessment was conducted. The study group had a significantly lower number of readmissions in the 90 days postintervention.  相似文献   
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