Effects of letrozole on serum estradiol and estrone in postmenopausal breast cancer patients and tolerability of treatment: a prospective trial using a highly sensitive LC –MS/MS (liquid chromatography–tandem mass spectrometry) method for estrogen measurement

ConclusionsLetrozole supresses E2 and E1 completely below the LLOQ of the LC –MS/MS in postmenopausal women. High pre-treatment E2 levels were associated with more joint and muscle pain during letrozole. Automated immunoassays are unsuitable for E2 monitoring during letrozole therapy due to poor sensitivity.
Source: Breast Cancer Research and Treatment - Category: Cancer & Oncology Source Type: research