Abstract 657: Perinatal factors and breast cancer risk: The CECILE study

Abstract

Abstract Objectives: Perinatal period and adolescence are key periods of breast cancer development with increased susceptibility to carcinogens. A high level of endogenous estrogens in utero was suggested as a possible risk factor for breast cancer in daughters. We investigated the role of perinatal factors in breast cancer in the CECILE study, a population-based case-control study. Methods: The CECILE study was conducted in two French départements (Côte d'Or, Ille-et-Vilaine) between 2005 and 2008. A total of 1232 incident breast cancer cases and 1317 population age-matched controls were included. An in-person interview was conducted using a standardized questionnaire to obtain information on recognized or suspected risk factors for breast cancer. A self-administered questionnaire was used to obtain information on perinatal factors and was returned by mail by 871 cases (71%) and 915 controls (69%). The perinatal questionnaire included information on parental characteristics (maternal and paternal age, maternal smoking status, hypertension or pre-eclampsia during pregnancy, exposure to diethylstilboestrol) and women’ birth characteristics (birth weight, length at birth, preterm birth, birth order and having been breast-fed). Analyses were conducted using unconditional logistic regression adjusting for age and recognized risk factors for breast cancer. Results: With the exception of maternal smoking (OR=0.57 [0.38-0.85]), there was no association between breast cancer risk and the other parental characteristics. We observed a J-shaped association between birth weight and breast cancer risk, with an OR of 1.54 [1.15-2.06] in women whose birth weight was 3500 grams or more as compared with women whose birth weight was 2500 to 3499 grams. We also observed an increased risk of breast cancer with an increase of birth order (OR=1.12 [0.91-1.37] for birth order 2 to 4; OR=1.42 [1.02-1.99] for birth order [[Unsupported Character - [[Unsupported Character - ]]]] 5, p trend=0.04). No association were observed for women who have been breast-fed, for length at birth or preterm birth. Conclusion: Our results support the hypothesized association between intrauterine estrogens exposure and risk of breast cancer in daughters. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 657. doi:1538-7445.AM2012-657