From: Is letrozole during ovarian stimulation useful in breast cancer patients undergoing fertility preservation to reduce early luteal progesterone levels following GnRH-agonist trigger?
Tumor characteristics
COSTLES group n = 84
Control group n = 77
ER and/or PR positive
63 (75.0%)
59 (76.6%)
T1/T2*
82 (97.6%)
75 (97.4%)
BRCA positive
7 (8.3%)
5 (6.5%)