Table 3. Statistical analysis of prognostic factors for OS.

Variable	Univariate P-value	Hazard ratio	95% CI
Age	0.0008	1.549	1.199–2.029
Histology	0.17	1.242	0.904–1.651
Clinical stage	<0.0001	2.577	1.993–3.329
ABCF2	0.0063	0.696	0.527–0.904

Age: >median age, histology: non-squamous cell carcinoma.

Clinical stage: III+IV, ABCF2: negative.

Hazard ratio refers to risk of death, with values <1.0 indicating reduced risk.

CI=confidence interval.