TABLE 1.

The relationship between various subtypes and BCBM

Subtype	ER	PR	HER2	Ki‐67	Incidence of CNS metastases	mOS after BCBM(months)	Reference
Luminal subtype	(+)	(+)	(−)	Low or high	~15%	7.1 ~ 9.3	2, 45, 120
HER2‐positive	(±)	(±)	(+)	High	~50%	11.5 ~ 18.9
TNBC	(−)	(−)	(−)	High	~35%	4.4 ~ 4.9

Abbreviations: BCBM, breast cancer brain metastasis; HER2, human epidermal growth factor receptor 2; ER, estrogen receptor; PR, progesterone receptor; TNBC, triple‐negative breast cancer; +, positive; −, negative; ±, positive, or negative.