Body fatness during childhood and adolescence and incidence of breast cancer in premenopausal women: a prospective cohort study

INTRODUCTION: Body mass index (BMI) during adulthood is inversely related to the incidence of premenopausal breast cancer, but the role of body fatness earlier in life is less clear. We examined prospectively the relation between body fatness during childhood and adolescence and the incidence of breast cancer in premenopausal women. METHODS: Participants were 109,267 premenopausal women in the Nurses' Health Study II who recalled their body fatness at ages 5, 10 and 20 years using a validated 9-level figure drawing. Over 12 years of follow up, 1318 incident cases of breast cancer were identified. Cox proportional hazards regression was used to compute relative risks (RRs) and 95% confidence intervals (CIs) for body fatness at each age and for average childhood (ages 5–10 years) and adolescent (ages 10–20 years) fatness. RESULTS: Body fatness at each age was inversely associated with premenopausal breast cancer incidence; the multivariate RRs were 0.48 (95% CI 0.35–0.55) and 0.57 (95% CI 0.39–0.83) for the most overweight compared with the most lean in childhood and adolescence, respectively (P for trend < 0.0001). The association for childhood body fatness was only slightly attenuated after adjustment for later BMI, with a multivariate RR of 0.52 (95% CI 0.38–0.71) for the most overweight compared with the most lean (P for trend = 0.001). Adjustment for menstrual cycle characteristics had little impact on the association. CONCLUSION: Greater body fatness during childhood and adolescence is associated with reduced incidence of premenopausal breast cancer, independent of adult BMI and menstrual cycle characteristics

A common 8q24 variant in prostate and breast cancer from a large nested case-control study.

Two recent studies independently identified polymorphisms in the 8q24 region, including a single nucleotide polymorphism (rs1447295), strongly associated with prostate cancer risk. Here, we replicate the overall association in a large nested case-control study from the National Cancer Institute Breast and Prostate Cancer Cohort Consortium using 6,637 prostate cancer cases and 7,361 matched controls. We also examine whether this polymorphism is associated with breast cancer among 2,604 Caucasian breast cancer cases and 3,118 matched controls. The rs1447295 marker was strongly associated with prostate cancer among Caucasians (P = 1.23 x 10(-13)). When we exclude the Multiethnic Cohort samples, previously reported by Freedman et al., the association remains highly significant (P = 8.64 x 10(-13)). Compared with wild-type homozygotes, carriers with one copy of the minor allele had an OR(AC) = 1.34 (99% confidence intervals, 1.19-1.50) and carriers with two copies of the minor allele had an OR(AA) = 1.86 (99% confidence intervals, 1.30-2.67). Among African Americans, the genotype association was statistically significant in men diagnosed with prostate cancer at an early age (P = 0.011) and nonsignificant for those diagnosed at a later age (P = 0.924). This difference in risk by age at diagnosis was not present among Caucasians. We found no statistically significant difference in risk when tumors were classified by Gleason score, stage, or mortality. We found no association between rs1447295 and breast cancer risk (P = 0.590). Although the gene responsible has yet to be identified, the validation of this marker in this large sample of prostate cancer cases leaves little room for the possibility of a false-positive result

The Association of Alcohol Consumption with Coronary Heart Disease Mortality and Cancer Incidence Varies by Smoking History

OBJECTIVE: To evaluate the effect of alcohol on coronary heart disease (CHD), cancer incidence, and cancer mortality by smoking history. DESIGN/SETTING: A prospective, general community cohort was established with a baseline mailed questionnaire completed in 1986. PARTICIPANTS: A population-based sample of 41,836 Iowa women aged 55–69 years. MEASUREMENTS: Mortality (total, cancer, and CHD) and cancer incidence outcomes were collected through 1999. Relative hazard rates (HR) were calculated using Cox regression analyses. MAIN RESULTS: Among never smokers, alcohol consumption (≥14 g/day vs none) was inversely associated with age-adjusted CHD mortality (HR, 0.40; 95% confidence interval [CI], 0.19 to 0.84) and total mortality (HR, 0.71; 95% CI, 0.55 to 0.92). Among former smokers, alcohol consumption was also inversely associated with CHD mortality (HR, 0.45; 95% CI, 0.23 to 0.88) and total mortality (HR, 0.78; 95% CI, 0.62 to 0.97), but was positively associated with cancer incidence (HR, 1.25; 95% CI, 1.03 to 1.51). Among current smokers, alcohol consumption was not associated with CHD mortality (HR, 1.05; 95% CI, 0.73 to 1.50) or total mortality (HR, 1.07; 95% CI, 0.92 to 1.25), but was positively associated with cancer incidence (HR, 1.30; 95% CI, 1.10 to 1.54). CONCLUSIONS: Health behavior counseling regarding alcohol consumption for cardioprotection should include a discussion of the lack of a decreased risk of CHD mortality for current smokers and the increased cancer risk among former and current smokers