Table 2.

Prognostic factors associated with local failure in 596 brainstem metastases (presented by Cox regression)

		Univariate			Multivariate
Factor	n	P	Hazard ratio*	95% CI	P	Hazard ratio*	95% CI
Age (y)		.090			007
<65	366		Ref			Ref
≥65	230		1.588	0.930-2.711		2.377	1.261-4.482
Gender		.064			.575
Male	286		Ref			Ref
Female	310		0.607	0.358-1.029		0.815	0.398-1.668
No. of lesions		.694
Single	142		Ref
Multiple	454		0.896	0.517-1.551
Active systemic metastases		.035			.143
No	197		Ref			Ref
Yes	399		1.957	1.049-3.653		1.683	0.838-3.380
Tumor volume (mL)		.482
<1	271		Ref
1-2	68	.283	1.551	0.696-3.458
>2	201	.376	1.308	0.722-2.369
Primary tumory†		.076			.568
Breast cancer	159		Ref			Ref
NSCLC	246	.212	1.642	0.754-3.576	.756	1.155	0.466-2.859
SCLC	16	.984	1.034	0.812-1.188	.985	1.036	0.814-1.189
RCC	60	.498	1.431	0.507-4.035	.954	0.964	0.279-3.338
Melanoma	84	.003	3.881	1.599-9.417	.135	2.450	0.757-7.926
GI tract origin	17	.983	1.022	0.972-1.029	.985	1.031	0.988-1.021
Tumor location		.591
Midbrain	126		Ref
Pons	345	.416	0.491	0.088-2.725
Medulla	45	.718	0.858	0.373-1.972
CP angle	14	.256	1.465	0.758-2.832
Midbrain-pons	44	.994	1.005	0.332-3.043
Pons-medulla	22	.728	0.738	0.133-4.095
Margin dose (Gy)		.110			.096
<16	172		Ref			Ref
16-19.9	319	.061	0.496	0.238-1.032	.809	0.883	0.322-2.422
≥20	105	.074	0.562	0.298-1.058	.043	0.478	0.234-0.977
Maximum dose (Gy)		.036			.039
<32	300		Ref			Ref
32-40	211	.073	0.469	0.205-1.073	.020	0.290	0.102-0.823
>40	85	.966	0.983	0.442-2.185	.389	0.660	0.256-1.700
Prior WBRT		.686
No	301		Ref
Yes	295		1.124	0.639-1.977
Prior chemotherapy		.995
No	155		Ref
Yes	441		1.002	0.570-1.760

Abbreviation: CI = confidence interval. Other abbreviations as in Table 1.

^*Higher hazard ratio, higher relative risk to local treatment failure.

^†Excludes unknown and other primary histology.