Table 1.

Baseline characteristics in ER-positive, ESR1-mutated metastatic breast cancer

Characteristics	Palbociclib plus aromatase inhibitor (n = 84)	Palbociclib plus fulvestrant (n = 88)
Median age	60 years	62 years
Prior adjuvant aromatase inhibitor therapy
Yes	37%	34%
No	63%	66%
Metastatic sites
Bone only	23%	22%
Visceral	49%	48%
Non-visceral ± bone	29%	31%
ECOG performance status
0	61%	57%
1-2	39%	43%