Table 2.

Univariate analysis for local failure after lung SBRT.

	Hazard Ratio (95% CI)	p-value
Patient age (continuous variable)	1.04 (0.99–1.10)	.15
Patient sex (female vs male)	0.56 (0.21–1.50)	.25
Histology (adenocarcinoma vs other)	0.61 (0.14–2.70)	.52
Primary tumor site (lung vs other)	0.35 (0.08–1.52)	.16
Tumor size (≥2.0 cm vs <2.0 cm)	0.94 (0.35–2.53)	.90
BED* of SBRT (≥100 Gy vs <100 Gy)	0.95 (0.31–2.96)	.93
EGFR mutation (present vs absent)	0.77 (0.22–2.71)	.68
PIK3CA mutation (present vs absent)	10.44 (2.16–50.46)	.004

Abbreviations: BED = biologically effective dose; Gy = Gray; SBRT = stereotactic body radiation therapy.

Note: For each binary variable, the second category following “vs” was the reference level (e.g. for sex, male was the reference), and the hazard ratio presents the risk of developing local failure for the first category vs the reference category (e.g. comparing to male the risk of developing local failure for female was 56%).

^*BED based on alpha/beta of 10.