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151.
PURPOSE: The relationships between mismatch repair (MMR) protein expression, microsatellite instability (MSI), family history, and germline MMR gene mutation status have not been studied on a population basis. METHODS: We studied 131 unselected patients with colorectal cancer diagnosed younger than age 45 years. For the 105 available tumors, MLH1, MSH2, MSH6, and PMS2 protein expression using immunohistochemistry (IHC) and MSI were measured. Germline DNA was screened for hMLH1, hMSH2, hMSH6, and hPMS2 mutations for the following patients: all from families fulfilling the Amsterdam Criteria for hereditary nonpolyposis colorectal cancer (HNPCC); all with tumors that were high MSI, low MSI, or that lacked expression of any MMR protein; and a random sample of 23 with MS-stable tumors expressing all MMR proteins. RESULTS: Germline mutations were found in 18 patients (nine hMLH1, four hMSH2, four hMSH6, and one hPMS2); all tumors exhibited loss of MMR protein expression, all but one were high MSI or low MSI, and nine were from a family fulfilling Amsterdam Criteria. Sensitivities of IHC testing, MSI (high or low), and Amsterdam Criteria for MMR gene mutation were 100%, 94%, and 50%, respectively. Corresponding positive predictive values were 69%, 50%, and 75%. CONCLUSIONS: Tumor IHC analysis of four MMR proteins and MSI testing provide a highly sensitive strategy for identifying MMR gene mutation-carrying, early-onset colorectal cancer patients, half of whom would have been missed using Amsterdam Criteria alone. Tumor-based approaches for triaging early-onset colorectal cancer patients for MMR gene mutation testing, irrespective of family history, appear to be an efficient screening strategy for HNPCC.  相似文献   
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The majority of men treated for prostate cancer will eventually develop castrate-resistant disease (CRPC) with metastases (mCRPC). There are several options for further treatment: chemotherapy, third-line hormone therapy, radium, immunotherapy, and palliation. Current ASCO guidelines for survivors of prostate cancer recommend that an individual’s information needs at all stages of disease are assessed and that patients are provided with or referred to the appropriate sources for information and support. Earlier reviews have highlighted the dearth of such services and we wished to see if the situation had improved more recently. Unfortunately, we conclude that there is still a lack of good-quality congruent information easily accessible specifically for men with mCRPC and insufficient data regarding the risks, harms, and benefits of different management plans. More research providing a clear evidence base about treatment consequences using patient reported outcome measures is required.  相似文献   
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Abstract

The authors obtained data from 335 breast cancer survivors and 6,880 non-cancer controls. They proposed (1) to determine whether, after treatment, the survivors were meeting the Center for Disease Control and Prevention/American College of Sports Medicine recommendations for physical activity and were similar to the controls in physical activity and (2) to compare the modes of activity of the 2 groups in frequency, min/session, and sessions/wk. Adjusted logistic regression analyses revealed that the breast cancer survivors engaged in as much moderate, vigorous, and combined physical activity as the non-cancer controls did. However, chi-square analyses showed that survivors engaged in more yard work than the controls did, whereas independent-sample t tests showed that the frequency and the total min/wk of stretching were significantly higher in breast cancer survivors compared with noncancer controls. Findings from the study suggest that breast cancer survivors engage in as much physical activity as controls do, but that the groups differ in specific activities.  相似文献   
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Tissue microarrays (TMAs) represent a powerful method for undertaking large‐scale tissue‐based biomarker studies. While TMAs offer several advantages, there are a number of issues specific to their use which need to be considered when employing this method. Given the investment in TMA‐based research, guidance on design and execution of experiments will be of benefit and should help researchers new to TMA‐based studies to avoid known pitfalls. Furthermore, a consensus on quality standards for TMA‐based experiments should improve the robustness and reproducibility of studies, thereby increasing the likelihood of identifying clinically useful biomarkers. In order to address these issues, the National Cancer Research Institute Biomarker and Imaging Clinical Studies Group organized a 1‐day TMA workshop held in Nottingham in May 2012. The document herein summarizes the conclusions from the workshop. It includes guidance and considerations on all aspects of TMA‐based research, including the pre‐analytical stages of experimental design, the analytical stages of data acquisition, and the postanalytical stages of data analysis. A checklist is presented which can be used both for planning a TMA experiment and interpreting the results of such an experiment. For studies of cancer biomarkers, this checklist could be used as a supplement to the REMARK guidelines.  相似文献   
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