The purpose of this study is to examine how key patient factors, including body size affect
how well letrozole suppresses circulating estrogen levels.
This study has two components: (1) Part A - an observational phase to evaluate the impact of
vitamin D and obesity on estrogen suppression in post-menopausal women already receiving
letrozole treatment, and (2) Part B - an interventional phase for women with body mass index
(BMI) > 25 kg/m2 to assess the effect of double AI dose on estrogen levels.
If BMI or other patient factors reduce the effectiveness of letrozole, modifications to
treatment recommendations and studies to test higher dosing of letrozole may be needed to
maximize the benefit of this treatment and minimize the risk of the breast cancer coming
back.
Phase:
N/A
Details
Lead Sponsor:
Samuel Lunenfeld Research Institute, Mount Sinai Hospital