Letrozole Is an Effective Adjuvant Treatment for Post-Menopausal Women Regardless of Weight
By Brian Hoyle
SAN ANTONIO, Tex -- December 12, 2016 -- A prospective study presented here at the 39th Annual San Antonio Breast Cancer Symposium (SABCS) has indicated that letrozole is an effective adjuvant treatment for post-menopausal women regardless of body mass index (BMI).
“No association was observed between BMI and residual estradiol in women using letrozole at standard doses,” said David W. Cescon, MD, Princess Margaret Cancer Centre, Toronto, Ontario, on December 8.
The study addressed the concern raised by the ALIQUOT study (J Clin Oncol 2012;30:2977-2980) of a correlation between BMI and residual estradiol in women with breast cancer treated with letrozole.
“These findings have created uncertainty about the use of aromatase inhibitors in overweight and obese women,” said Dr. Cescon.
The current prospective, open-label, single-arm study measured oestrogen levels in 112 post-menopausal women who were treated for 1 month using adjuvant letrozole 25 mg/day.
Post-menopausal women with oestrogen receptor-positive (ER)-positive and/or progesterone receptor-positive (PR)-positive breast cancer who received adjuvant letrozole for at least 3 months were eligible. Exclusion criteria included abnormal liver or renal function and metastatic disease.
Adherence determined by patient diaries and supervised pill counts was 90%, with no patient missing more than 2 scheduled doses.
Mean standard estradiol levels were not affected by treatment (2.81 ± 1.15 pg/ml at baseline and 2.69 ± 1.01 pg/ml at day 29 of letrozole therapy).
There were no associations between residual estradiol levels at day 29 and levels of vitamin D, C-reactive protein or leptin.
“These results provide reassurance that letrozole is an appropriate treatment in overweight and obese women,” said Dr. Cescon.
[Presentation title: Association Between BMI and Residual Estradiol Levels in Post-Menopausal Women Using Adjuvant Letrozole: Results of a Prospective Study. Abstract P2-09-14]