Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology
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Cancer Epidemiol. Biomarkers Prev. · Oct 2007
Relationship between age maximum height is attained, age at menarche, and age at first full-term birth and breast cancer risk.
Several pubertal and reproductive events are well established risk factors for breast cancer. Age maximum height attained is an understudied potential breast cancer risk factor that may affect risk through mechanisms different from those of other pubertal and reproductive events. We assessed the relationships between different pubertal/reproductive events and risk of different types of breast cancer in a prospective cohort of 27,536 women. ⋯ This association was primarily limited to more aggressive tumors, specifically those that were estrogen receptor-negative (hazard ratio, 1.9; 95% CI, 1.0-3.9) and diagnosed at a regional or distant stage (hazard ratio, 1.8; 95% CI, 1.0-3.1). There was no difference in the relation of age at menarche with breast cancer by tumor stage, whereas late age at first full-term pregnancy primarily increased risks of less-aggressive disease, including lobular, estrogen receptor-positive, and localized stage tumors. Age at maximum height seems to be an independent risk factor for breast cancer that is more strongly associated with relatively aggressive tumors that have a poorer prognosis compared with the types of tumors that are associated with ages at menarche and first full-term birth.