Table 5.

Univariate and multivariate analysis for overall survival (OS) predictors in 50 patients with BCBM

Characteristics		No.	Mean (months)	P-value (univariate)	P-value (multivariate)	Hazard ratio	95% CI
Age (year)	< 60	35	31.5	0.265	0.054	1	0.987–4.162
	≥ 60	15	21.6			2.027
Sex	Female	49	---	---	---
	Male	1	---
Molecular type	Non-TN	35	35.0	< 0.001	< 0.001	1	2.513–14.285
	TN	15	9.1			5.992
CAF pattern	Type B	20	29.3	0.498	0.238	1	0.306–1.343
	Others	30	25.9			0.641
PDGFR-β	Low	27	27.4	0.721	---
	High	23	27.8
α-SMA	Low	27	22.3	0.211	---
	High	23	32.6
Tumor location	Supratentorial	37	27.6	0.607	---
	Infratentorial	13	28.2
Extracranial Mets	Absent	12	38.3	0.263	---
	Present	38	24.4
BM symptom	Mild to moderate	31	30.4	0.457	---
	Severe	19	24.6
KPS	≥ 80	32	30.6	0.454	---
	< 80	18	23.6
BM multiplicity	Single	24	26.9	0.645	---
	Multiple	26	26.5
BM development	Metachronous	49	---	---	---
	Synchronous	1	---
BM size	< 4 cm	22	31.2	0.643	0.427	1	0.639–2.879
	≥ 4 cm	28	25.5			1.357
Peritumoral edema	Mild to moderate	27	26.1	0.791	---
	Severe	23	30.7
Tumor nature	Solid	27	33.7	0.197	---
	Cystic or mixed	23	22.1
Resection degree	Partial to subtotal	12	20.8	0.442	---
	Gross total	38	29.8
Postoperative RT/GKS	Absent	16	19.2	0.153	0.111	1	0.265–1.146
	Present	34	31.8			0.551

BC; breast cancer, BM; brain metastasis, α-SMA; alpha-smooth muscle actin, CAF; cancer-associated fibroblast, GKS; gamma knife radiosurgery, KPS; Karnofsky performance score, Mets; metastasis, PDGFR-β; platelet-derived growth factor receptor-beta, RT; radiation treatment, TN; triple negative