Breast cancer is the most frequent cancer in women in western countries. A number of risk factors are now known, but the etiology of the disease is not fully understood. The aim of this study was to determine the effects of reproductive, anthropometric and environmental factors on cancer onset. PATIENTS AND
Methods
934 women who developed a non-hereditary breast cancer were recruited from different hospitals in the Auvergne region (France) and completed a questionnaire.
Results
The use of oral contraceptives (OC) increased the risk of early cancer development (odds ratio = 1.84, 95% confidence interval = 1.38-2.44). The age at first OC use appeared to be a major factor since the risk decreased when OC use was after the age of 23 years (odds ratio = 0.52, 95% confidence interval = 0.34-0.79). A duration of breast-feeding greater than 26 weeks decreased the risk of early cancer development (odds ratio = 0.62, 95% confidence interval = 0.39-0.97). No overall association was found with anthropometric or lifestyle factors and early age at breast cancer onset.
Conclusion
OC use, age at first OC use and lactation were significantly associated with an early age at breast cancer onset. Thus, a number of "risk factors" could be considered as "early onset risk factors".
oral contraceptive use early onset breast cancer risk factors, age at first oral contraceptive use breast cancer onset, breastfeeding duration protective early breast cancer development, oral contraceptive young women breast cancer early age onset, COSA program breast cancer population-based study France, reproductive risk factors non-hereditary breast cancer onset age, OC use before age 23 increased breast cancer risk, breastfeeding 26 weeks protective breast cancer early development, early onset risk factors oral contraceptive lactation breast cancer, hormonal contraception breast cancer age-dependent risk
Cite this article
Delort, L., Kwiatkowski, F., Chalabi, N., Satih, S., Bignon, Y., & Bernard-Gallon, D. (2007). Risk factors for early age at breast cancer onset--the "COSA program" population-based study. Anticancer research, 27(2), 1087-1094.
Delort L, Kwiatkowski F, Chalabi N, Satih S, Bignon Y, Bernard-Gallon D. Risk factors for early age at breast cancer onset--the "COSA program" population-based study. Anticancer Res. 2007;27(2):1087-1094.
Delort, Laetitia, et al. "Risk factors for early age at breast cancer onset--the "COSA program" population-based study." Anticancer research, vol. 27, no. 2, 2007, pp. 1087-1094.
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