American Association for Cancer Research

September 2007 CEBP Highlights

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Selected Articles from the September 2007 Issue

The articles referenced in this Highlights section will be available online in HTML and PDF formats to all interested users at no charge until the next issue of Cancer Epidemiology, Biomarkers & Prevention is published. Click on the article title to view the complete article.

View the Table of Contents for the September 2007 issue of Cancer Epidemiology, Biomarkers & Prevention.


Iron-generated Oxidative Stress Increases Breast Cancer Risk

Hong et al.

Page 1784

Oxidative stress resulting from excess reactive oxygen species and/or deficiencies in antioxidant capabilities may play a role in breast cancer etiology. In a nested case-control study of postmenopausal women, Hong and coauthors examined relationships between breast cancer risk and genetic polymorphisms in enzymes involved in the generation and removal of iron-mediated reactive oxygen species. Their results indicated that women with genotypes resulting in potentially higher levels of iron-generated oxidative stress may be at increased risk of breast cancer, and that this association may be most relevant among women with high iron intake. 
 

Body Size Not to Blame for Breast Cancer in Black Women

Palmer et al.

Page 1795

The relation of body mass index (BMI) and weight gain to breast cancer risk is complex, and little information is available on black women, among whom the prevalence of obesity is high. Palmer and colleagues assessed BMI and weight gain in relation to breast cancer and found that being overweight at age 18 is associated with a reduced risk of both pre- and postmenopausal breast cancer in African-American women. The lack of an association between obesity and receptor-negative tumors in postmenopausal African-American women may partially explain why breast cancer incidence in older black women is not high relative to other ethnic groups in spite of the high prevalence of obesity in black women.


Weight Gain Decreases Breast Cancer Survival

Cleveland et al.

Page 1803

To examine the effects of pre-diagnostic obesity and weight gain throughout the life course on survival after a breast-cancer diagnosis, Cleveland and colleagues conducted a follow-up study among a population-based sample of women diagnosed with first, primary invasive and in situ breast cancer between 1996-1997. Women diagnosed with postmenopausal breast cancer who gained greater than 12.7 kg after age of 50 up to the year prior to diagnosis had a 2- to 3-fold increased risk of death due to all-causes and breast cancer. These results indicated that high levels of pre-diagnostic weight and substantial weight gain throughout life can decrease survival in premenopausal and postmenopausal breast cancer patients.


Greater body fatness during childhood is associated with reduced risk of premenopausal breast cancer, but few studies have addressed the relation of adiposity with sex hormones in girls. Baer and colleagues prospectively examined associations between adiposity and circulating levels of sex hormones and sex hormone-binding globulin (SHBG) among 286 girls in the Dietary Intervention Study in Children. Participants were 8 to 10 years old at baseline and were followed for an average of seven years. Estrogen and progesterone concentrations were similar across BMI quartiles. The findings, nonetheless, suggested that DHEAS and SHBG levels in girls may differ by degree of adiposity.


Self-reported Polyps have High Predictive Value

Madlensky et al.

Page 1898

Colorectal adenomas and other types of polyps are commonly used as endpoints or risk factors in epidemiologic studies. However, it is not known how accurately patients are able to self-report the presence or absence of adenomas following colonoscopy. The positive predictive value for self-reported polyp was 80.9%, and the negative predictive value was 85.8%. Participants with a previous diagnosis of colorectal cancer had a lower negative predictive value (76.2%) than participants with no personal history of colorectal cancer (89.0%). Madlensky and coauthors concluded that predictive values for self-reports of polyps are fairly high, but researchers needing accurate polyp data should obtain medical record confirmation.