Table 3
A summary of research studies on neoadjuvant endocrine therapy

Study	Design	Subject	Treatment	Clinical response (%)	Breast-conserving rate (%)
Eiermann et al., 2001 [44]	Randomized	337 Patients	Letrozole	55	45
	Double-blind	Postmenopausal	Tamoxifen	36	35
	Multicenter	ER/PR (+)	For 4 mo	P<0.001	P=0.022
IMPACT, 2005 [46]	Randomized	330 Patients	Tamoxifen	36	22
		Postmenopausal	Anastrozole	37	46
		ER (+)	Tamoxifen+anastrozole	39	26
		Operable	For 3 mo		P=0.03
		Locally advanced
PROACT, 2006 [43]	Randomzed	451 Patients	Tamoxifen	46.2	30.8
	Double -blind	Postmenopausal	Anastrozole	50	43
	Multicenter	ER/PR (+)	For 1 mo		P=0.04
		Operable			ACOSOG
		Locally advanced
Z1031, 2011 [47]	Randomized	377 Patients	Exemestane	62.9
	Phase II	Letrozole		74.8
	Postmenopausal	Anastrozole		69.1
	ER (+)	For 16–18 wk		For all patients:
	Clinical stage II-III			No differences in surgical results, PEPI score and Ki-67 suppression
STAGE, 2012 [45]	Randomized	197 Patients	Goserelin+anastrozole		70.4
	Double-blind	Premenopausal	Goserelin+tamoxifen		50.5
	Phase III	ER (+)	For 6 mo		P=0.004
	Multicenter	HER2 (-)
		Operable

ER, estrogen receptor; PR, progesterone receptor; IMPACT, immediate preoperative anastrozole, tamoxifen, or combined with tamoxifen; PROACT, pre-operative "arimidex" compared to tamoxifen; ACOSOG, American college of surgeons oncology group; PEPI, Preoperative endocrine prognostic index.