Table 2. Univariate analysis and multivariate analysis with regard to OS in 381 patients with pulmonary neuroendocrine tumors.

Variables	Univariate analysis				Multivariate analysis
	P value	HR	95% CI		P value	HR	95% CI
Gender (female, male)	0.476	0.882	0.625–1.245		0.850	1.042	0680–1.598
Age (≤60, >60)	0.430	1.120	0.845–1.486		0.117	1.270	0.941–1.714
Smoking history (ever, never)	0.219	1.221	0.888–1.678		0.888	0.958	0.529–1.737
Drinking history (ever, never)	0.101	1.295	0.950–1.764		0.327	1.314	0.761–2.271
Tumor size (≤4 cm, >4 cm)	0.002*	1.577	1.188–2.092		0.708	1.080	0.723–1.612
T stage (T1–T2, T3–T4)	0.001*	1.646	1.216–2.227		0.291	1.270	0.815–1.979
Lymph node metastasis (negative, positive)	<0.001*	2.127	1.589–2.848		<0.001*	2.307	1.554–3.427
Distant metastasis (negative, positive)	0.241	1.978	0.632–6.191		0.090	2.829	0.849–9.429
TNM stage (I/II, III/IV)	<0.001*	2.167	1.632–2.876		0.059	1.530	0.984–2.378
Operation time (<200 min, ≥200 min)	0.028*	1.426	1.039–1.956		0.034*	1.432	1.028–1.994
Intraoperative blood loss (<200 mL, ≥200 mL)	0.354	1.143	0.861–1.518		0.397	0.878	0.650–1.186
Treatment (surgery only, surgery with adjuvant therapy)	0.869	1.025	0.763–1.378		<0.001*	0.476	0.334–0.679
SII (<479.72, ≥479.72)	<0.001*	2.189	1.641–2.920		0.002*	1.657	1.199–2.291
NLR (<2.27, ≥2.27)	<0.001*	2.284	1.717–3.038		<0.001*	1.817	1.331–2.479
PLR (<117.05, ≥117.05)	<0.001*	1.942	1.453–2.597		0.001*	1.707	1.235–2.361
PNI (<0.19, ≥0.19)	<0.001*	0.582	0.438–0.774		0.044*	0.721	0.524–0.991

*, P less than 0.05 is significant. CI, confidence interval; OS, overall survival; HR, hazard ratio; SII, systemic immune-inflammation index; NLR, neutrophil–lymphocyte ratio; PLR, platelet–lymphocyte ratio; PNI, prognostic nutritional index