Table 3.

Multivariate Logistic Regression for Postoperative Nodal Upstaging

Characteristics	Nodal Upstaging
	Sig	OR	LL	UL	pa
ENS (as a continuous variable)	< 0.001	1.062	1.030	1.096
ELN (as a continuous variable)	0.023	0.964	0.919	0.996
Lymph node dissection (yes vs. no)	0.998	1.334	0.658	3.125
Sex (male vs. female)	0.483	0.887	0.635	1.239
Operated side (left vs. right)	0.001	1.777	1.283	2.462
Tumor location (lower and middle vs. upper)					0.001
Middle lobe vs. upper lobe	0.006	2.386	1.286	4.426
Lower lobe vs. upper lobe	0.048	0.702	0.493	0.998
pT					0.007
T2 vs. T1	0.002	1.676	1.215	2.313
T3 vs. T1	0.350	2.104	0.442	10.010
T4 vs. T1	0.098	5.591	0.729	42.904
Histology ([others, LCC, ASC, ADC] vs. SCC)					0.001
ADC vs. SCC	0.137	0.349	0.087	1.395
ASC vs. SCC	0.980	1.017	0.277	3.724
LCC vs. SCC	0.972	0.975	0.235	4.038
Others vs. SCC	0.308	2.062	0.513	8.285
Grade of differentiation ([others, poor, moderate] vs. well)					0.001
Moderate vs. well	0.007	4.221	1.487	11.985
Poor vs. well	< 0.001	7.323	2.455	21.842
Others vs. well	0.035	3.622	1.094	11.988
Surgical approach (thoracotomy vs. VATS)	< 0.001	2.472	1.557	3.927
Types of resection ([wedge resection, segmentectomy] vs. lobectomy)					0.765
Segmentectomy vs. lobectomy	0.465	0.709	0.282	1.782
Wedge resection vs. lobectomy	0.998	0.895	0.195	2.785

ADC, adenocarcinoma; ASC, adenosquamous carcinoma; CI, confidence interval; ELN, examined lymph node; ENS, examined node station; LCC, large cell carcinoma; LL, lower limit of 95% CI; LNR, lymph node ratio (the ratio of metastatic lymph nodes to the total number of lymph nodes examined); OR, odds ratio; SCC, squamous cell carcinoma; Sig, significance; UL, upper limit of 95% CI; VATS, video-assisted thoracic surgery.

^aInteraction test p value.