Table 1

Clinicopathological characteristics and treatment of the BCBM patients

		n	%
Age at time of BCBM	Mean	52 years
	SD	10.3
	Range	29–79 years
Gender	Female	97	99.0
	Male	1	1.0
Breast cancer subtype of BM	TNBC	26	26.6
	HR+/HER2+	15	15.3
	HR+/HER2−	21	21.4
	HR−/HER2+	36	36.7
Number of BM sites	1	91	92.9
	2	5	5.1
	3 or more	2	2.0
KPS	90	31	31.6
	70–80	50	51.0
	60 or less	17	17.4
Metastatic sites	Frontal lobe	22	22.5
	Temporal lobe	11	11.2
	Parietal lobe	5	5.1
	Occipital lobe	11	11.2
	Cerebellum	32	32.7
	Others	17	17.3
De novo stage IV breast cancer	Yes	83	84.7
	No	15	15.3
Systemic therapy after BM diagnosis	Yes	84	85.7
	No	14	14.3
Radiotherapy after BM diagnosis	Yes	74	75.5
	No	24	24.5

BCBM, breast cancer brain metastases; HER2, human epidermal growth factor receptor 2; HR, hormone receptor; KPS, Karnofsky performance status; TNBC, triple-negative breast cancer.