Table 2. Univariate analysis of clinical-pathologic potential prognostic factors.

Patient characteristics	5-year overall survival			5-year disease-free survival
	Rate (%)	P value		Rate (%)	P value
Sex		0.880			0.560
Male	59.7			58.1
Female	53.4			46.1
Tumor location		0.670			0.830
Right	52.8			55.6
Left	59.6			48.3
Histology		0.0015			0.0002
Squamous cell carcinoma	71.8			67.3
Adenocarcinoma	49.9			47.2
Large-cell carcinoma	25.0			16.7
Type of resection		0.190			0.321
Sublobar resection	37.5			37.5
Lobectomy	55.5			50.9
Pneumonectomy	68.7			62.5
Compartment of lymph node metastases
Hilar, yes/no	55.2/58.9	0.709		53.8/47.7	0.417
Interlobar, yes/no	59.6/44.0	0.241		55.3/39.7	0.195
Pulmonary, yes/no	52.8/59.2	0.260		46.7/55.6	0.296
Extranodal lymph node involvement		0.570			0.399
Yes	59.3			56.8
No	54.6			49.0
Lymph node involvement due to		0.350			0.880
Direct tumor involvement	59.5			52.2
Metastatic lymph node involvement	53.2			51.0
Number of lymph node metastases		0.126			0.045
Single	64.5			62.9
Multiple	49.3			42.3
Central tumor location (<2 cm)		0.170			0.386
Yes	62.3			56.9
No	50.3			47.1
T descriptor		0.580			0.460
pT1	59.1			56.0
pT2	55.5			50.1
UICC stage		0.051			0.011
IIA	63.0			60.0
IIB	38.9			31.1
Adjuvant chemotherapy		0.560			0.639
Yes	57.9			53.9
No	55.2			50.3

UICC, Union for International Cancer Control.