Phytoestrogen intake from foods, during adolescence and adulthood, and risk of breast cancer by estrogen and progesterone receptor tumor subgroup among Ontario women

Phytoestrogen intake may reduce breast cancer risk and limited evidence suggests this association may hold for hormone receptor-positive tumors only. The study aims were to assess whether the association between phytoestrogen intake during adolescence and adulthood and breast cancer risk varies by estrogen and progesterone receptor (ERPR) tumor subgroup. Cases were identified from the Ontario Cancer Registry (2002-2003), and ERPR status was …