The association of women’s birth size with risk of molecular breast cancer subtypes: a cohort study
Marie S. Sandvei,
Signe Opdahl,
Marit Valla,
Pagona Lagiou,
Ellen Veronika Vesterfjell,
Tor Vikan Rise,
Tina Syvertsen Overrein,
Anette H. Skjervold,
Monica J. Engstrøm,
Anna M. Bofin,
Lars J. Vatten
Affiliations
Marie S. Sandvei
Faculty of Medicine and Health Sciences, Department of Public Health and Nursing, Norwegian University of Science and Technology
Signe Opdahl
Faculty of Medicine and Health Sciences, Department of Public Health and Nursing, Norwegian University of Science and Technology
Marit Valla
NTNU, Faculty of Medicine and Health Sciences, Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology
Pagona Lagiou
Department of Hygiene, Epidemiology and Medical Statistics, School of Medicine, National and Kapodistrian University of Athens
Ellen Veronika Vesterfjell
Department of Pathology, St. Olavs Hospital HF, Trondheim University Hospital
Tor Vikan Rise
NTNU, Faculty of Medicine and Health Sciences, Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology
Tina Syvertsen Overrein
Department of Pathology, St. Olavs Hospital HF, Trondheim University Hospital
Anette H. Skjervold
NTNU, Faculty of Medicine and Health Sciences, Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology
Monica J. Engstrøm
NTNU, Faculty of Medicine and Health Sciences, Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology
Anna M. Bofin
NTNU, Faculty of Medicine and Health Sciences, Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology
Lars J. Vatten
Faculty of Medicine and Health Sciences, Department of Public Health and Nursing, Norwegian University of Science and Technology
Abstract Background Because birth size appears to be positively associated with breast cancer risk, we have studied whether this risk may differ according to molecular breast cancer subtypes. Methods A cohort of 22,931 women born 1920–1966 were followed up for breast cancer occurrence from 1961 to 2012, and 870 were diagnosed during follow-up. Archival diagnostic material from 537 patients was available to determine molecular breast cancer subtype, specified as Luminal A, Luminal B (human epidermal growth factor receptor 2 (HER2)-), Luminal B (HER2+), HER2 type, and Triple negative (TN) breast cancer. Information on the women’s birth weight, birth length and head circumference at birth was used to estimate hazard ratios (HR) with 95% confidence intervals (CI) for each molecular subtype, applying Cox regression, and stratified by maternal height. Results Birth length (per 2 cm increments) was positively associated with Luminal A (HR = 1.2, 95% CI, 1.0–1.3), Luminal B (HER2+) (HR = 1.3, 95% CI, 1.0–1.7), and TN breast cancer (HR = 1.4, 95% CI, 1.0–1.9). No clear association was found for birth weight and head circumference. The positive associations of birth length were restricted to women whose mothers were relatively tall (above population median). Conclusion We found a positive association of birth length with risk of Luminal A, Luminal B (HER2+) and TN breast cancer that appears to be restricted to women whose mothers were relatively tall. This may support the hypothesis that breast cancer risk is influenced by determinants of longitudinal growth and that this finding deserves further scrutiny.
