Original Contribution Human Chorionic Gonadotropin and Alpha-Fetoprotein Concentrations in Pregnancy and Maternal Risk of Breast Cancer: A Nested Case-Control Study

• Main Authors: Annekatrin Lukanova, Ritu Andersson, Marianne Wulff, Anne Zeleniuch-jacquotte, Kjell Grankvist, Laure Dossus, Yelena Afanasyeva, Robert Johansson, Alan A. Arslan, Per Lenner, Paolo Toniolo, Eva Lundin
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2008
• Subjects: Northern Sweden
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.573.6318; http://aje.oxfordjournals.org/content/168/11/1284.full.pdf

Pregnancy hormones are believed to be involved in the protection against breast cancer conferred by preg-nancy. The authors explored the association of maternal breast cancer with human chorionic gonadotropin (hCG) and a-fetoprotein (AFP). In 2001, a case-control study was nested within the Northern Sweden Maternity Cohort, an ongoing study in which blood samples have been collected from first-trimester pregnant women since 1975. Cases (n 210) and controls (n 357) were matched for age, parity, and date of blood donation. Concentrations of hCG and AFP were measured by immunoassay. No overall significant association of breast cancer with either hCG or AFP was observed. However, women with hCG levels in the top tertile tended to be at lower risk of breast cancer than women with hCG levels in the lowest tertile in the whole study population and in subgroups of age at sampling, parity, and age at cancer diagnosis. A borderline-significant decrease in risk with high hCG levels was observed in women who developed breast cancer after the median lag time to cancer diagnosis (14 years; odds ratio 0.53, 95 % confidence interval: 0.27, 1.03; P 0.06). These findings, though very preliminary, are consistent with a possible long-term protective association of breast cancer risk with elevated levels of circulating hCG in the early stages of pregnancy. alpha-fetoproteins; breast neoplasms; chorionic gonadotropin; pregnancy; prospective studies Abbreviations: AFP, a-fetoprotein; hCG, human chorionic gonadotropin.