Table 3. Clinical patient characteristics and associations with disease-free and overall survival from Cox proportional hazards regression.

Patient characteristics	Category	Number	DFS (Nevents=34)			OS (Nevents=26)
			HR (95% CI)	P value		HR (95% CI)	P value
Age (years)	Mean [range]	69.2 [48–88]	1.06 (0.76–1.47)	0.74		1.06 (0.72–1.55)	0.78
Sex	M	32	Ref	–
	F	32	0.91 (0.91–1.78)	0.77		1.13 (0.52–2.45)	0.75
Smoking history	Never	3	Ref	–
	Former	59	0.85 (0.2–3.58)	0.83
	Current	2	4.8 (0.64–32)	0.13
Pack years	Mean [range]	38.8 [2–100]	1.07 (0.77–1.49)	0.68		1.28 (0.87–1.89)	0.21
Clinical stage	IA	34	Ref	–
	IB	14	0.54 (0.2–1.46)	0.23		0.22 (0.05–0.96)	0.04
	IIA	10	1.22 (0.49–3.06)	0.67		1.01 (0.37–2.75)	0.98
	IIB	6	1.25 (0.43–3.68)	0.68		0.55 (0.13–2.45)	0.44
Pathological size	Mean (median)	3.88 (3.05)	1.06 (0.76–1.47)	0.74		0.90 (0.61–1.35)	0.62
Pathological node status	pN0	54	Ref	–
	pN1	10	3.24 (1.49–7.02)	0.003		4.16 (1.70–11)	0.002
Pre-Op mediastinal staging	No	34	Ref	–
	Yes	30	2.06 (1.04–4.06)	0.04		2.04 (0.93–4.47)	0.08
Histology	Adenocarcinoma	33	Ref	–
	Squamous cell carcinoma	26	1.04 (0.51–2.11)	0.92		0.80 (0.36–1.79)	0.58
	Mixed	5	1.33 (0.39–4.54)	0.65		0.38 (0.05–2.92)	0.36
Tumor grade	Well	8	Ref	–
	Mod	45	3.12 (0.74–13)	0.12		0.93 (0.32–2.72)	0.89
	Poor	11	3.55 (0.74–17)	0.11		0.93 (0.23–3.73)	0.92
Adjuvant chemotherapy	No	52	Ref	–
	Yes	12	2.49 (1.18–5.23)	0.02		3.04 (1.33–6.96)	0.01
History of hypertension	No	27	Ref	–
	Yes	37	2.81 (1.31–6.03)	0.008		2.74 (1.13–6.67)	0.03
History of diabetes	No	52	Ref	–
	Yes	12	0.89 (0.37–2.16)	0.8		0.87 (0.32–2.33)	0.78
DLCO	Mean (median)	76.6 (75.0)	0.63 (0.43–0.92)	0.02		0.55 (0.35–0.87)	0.01
Hemoglobin	Mean (median)	12.8 (12.9)	0.74 (0.52–1.04)	0.08		0.80 (0.54–1.18)	0.26
Creatinine	Mean (median)	0.9 (1.0)	0.70 (0.47–1.04)	0.08		0.87 (0.59–1.27)	0.46
Recurrence location	Local	10	–			–
	Contralateral	14
	Distant	10
Extent of surgery	Lobectomy	63	–			–
	Pneumonectomy	1

DLCO, diffusing capacity of the lungs for carbon monoxide.