Early Life Processes, Endocrine Mediators and Number of Susceptible Cells in Relation to Breast Cancer Risk


Principal Investigator:
Dimitrios Trichopoulos, Vincent L Gregory Professor of Cancer Prevention


Dates of Research:
March 15, 2005 — April 14, 2011


We have proposed that breast cancer originates as early in life as during the intrauterine period and that mammary gland mass, as contrasted to breast size that largely depends on body fat, is a critical determinant of the risk of this disease. Thus, intrauterine and early life events and conditions could affect the number of mammary gland cells at risk for transformation and, ultimately, breast cancer risk. Supportive evidence has accumulated that certain early life events and conditions, notably birth size and early life growth are indeed associated with breast cancer risk, whereas several correlates of mammary gland mass, including mammographic density, have been shown to be predictors of this risk. This project will conduct a series of five component studies that allow a reconstruction of the series of phenomena that link early life exposures to mammary gland mass (and thus number of susceptible cells) to breast cancer in adult life. There has been little progress in the prevention of breast cancer, despite efforts in molecular, clinical and epidemiological research which have focused on adult life exposures and experiences. Indeed, the incidence of breast cancer in most countries of the world tends to increase. A possible reason is that a window of opportunity for the prevention of breast cancer lies much earlier in life, as early as in utero or in the first years of life. The planned project explores the link between early life events and conditions and adult life breast cancer risk, with a view to identify opportunities for prevention of this disease.