Journal of the National Cancer Institute
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J. Natl. Cancer Inst. · Nov 2006
Meta AnalysisMeta-analyses of observational and genetic association studies of folate intakes or levels and breast cancer risk.
Evidence from case-control studies suggests that increasing dietary folate intake is associated with a reduced risk of breast cancer. However, large cohort studies have found no such association, and animal studies suggest that folate supplementation may promote tumorigenesis. We conducted a meta-analysis to summarize the available evidence from observational studies on this issue and a meta-analysis of the association between a common polymorphism in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene, a key enzyme in folate metabolism, and breast cancer risk. ⋯ A lack of dietary folate intake is not associated with the risk of breast cancer.
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J. Natl. Cancer Inst. · Nov 2006
Development of quality indicators for patients undergoing colorectal cancer surgery.
Colorectal cancer is the second most common cancer type among new cancer diagnoses in the United States. Attention to the quality of surgical care for colorectal cancer is of particular importance given the increasing numbers of colorectal cancer resections performed in the aging population. A National Cancer Institute-sponsored consensus panel produced guidelines for colorectal cancer surgery in 2000. We have updated and extended that work by using a formal process to identify and rate quality indicators as valid for care during the preoperative, intraoperative, and postoperative periods. ⋯ The RAND/UCLA Appropriateness Methodology can be used to identify and rate indicators of high-quality perioperative care for patients undergoing surgery for colorectal cancer. The indicators can be used as quality performance measures and for quality-improvement programs.
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J. Natl. Cancer Inst. · Nov 2006
Multicenter StudyNew primary neoplasms of the central nervous system in survivors of childhood cancer: a report from the Childhood Cancer Survivor Study.
Subsequent primary neoplasms of the central nervous system (CNS) have frequently been described as late events following childhood leukemia and brain tumors. However, the details of the dose-response relationships, the expression of excess risk over time, and the modifying effects of other host and treatment factors have not been well defined. ⋯ Exposure to radiation therapy is the most important risk factor for the development of a new CNS tumor in survivors of childhood cancers. The higher risk of subsequent glioma in children irradiated at a very young age may reflect greater susceptibility of the developing brain to radiation.
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J. Natl. Cancer Inst. · Nov 2006
Comparative StudyRe-evaluating adjuvant breast cancer trials: assessing hormone receptor status by immunohistochemical versus extraction assays.
Tumor levels of steroid hormone receptors, a factor used to select adjuvant treatment for early-stage breast cancer, are currently determined with immunohistochemical assays. These assays have a discordance of 10%-30% with previously used extraction assays. We assessed the concordance and predictive value of hormone receptor status as determined by immunohistochemical and extraction assays on specimens from International Breast Cancer Study Group Trials VIII and IX. These trials predominantly used extraction assays and compared adjuvant chemoendocrine therapy with endocrine therapy alone among pre- and postmenopausal patients with lymph node-negative breast cancer. Trial conclusions were that combination therapy provided a benefit to pre- and postmenopausal patients with estrogen receptor (ER)-negative tumors but not to ER-positive postmenopausal patients. ER-positive premenopausal patients required further study. ⋯ Trial conclusions in which ER status (for all patients) or PgR status (for postmenopausal patients) was determined by immunohistochemical assay supported those determined by extraction assays. However, among premenopausal patients, trial conclusions drawn from PgR status differed--immunohistochemically determined PgR status could predict response to endocrine therapy, unlike that determined by the extraction assay.