Table 1.

Clinicopathological Characteristics of Patients with pN2 Lung cancer (1990–2009) by time period

Characteristics	1990–1994	1995–1999	2000–2004	2005–2009	Total
Age (years)
<65/≥65	49/25	38/30	36/20	46/43	169/118
Sex
male/female	50/24	40/28	39/17	51/38	180/107
Clinical T factor
cT1/2/3/4	23/36/14/1	28/30/8/2	23/23/7/3	34/48/7/0	108/137/36/6
Clinical N factor
cN 0/1/2	34/10/30	36/15/17	33/18/5	53/24/12	156/67/64
Pulmonary Metastasis
pm0/1/2	43/27/4	56/11/1	42/11/3	77/10/2	218/59/10
Operation
lobectomy/pneumonectomy	57/17	61/7	50/6	78/11	246/41
Number of zone
multiple/single	18/56	15/53	14/42	28/61	75/212
Skip pN2
Skip/nonskip	41/33	36/32	22/34	61/28	127/160
Pathological T factor
pT1a/1b/2a/2b/3/4	1/10/19/1/38/5	7/10/18/5/24/4	5/8/19/2/17/5	13/12/37/6/19/2	26/40/93/14/98/16
Tumor size
>31 mm/≤30 mm	46/28	40/28	28/28	45/44	159/128
Adjuvant therapy
no/chemotherapy/radiation/chemoradiation	33/20/16/5	61/0/7/0	51/2/3/0	38/49/1/1	183/71/27/6
Pathological type
Adenocarcinoma/others	53/21	44/24	42/14	75/14	214/73
EGFR mutation
Yes/no/unknow	0/0/74	0/0/68	0/0/56	20/21/48	20/21/246
Recurrence
Recurrence/not	48/26	45/23	39/17	65/24	196/91
Median recurrence time (month)	11	13	14	14	13
Recurrence site
Local/distant/distant and local	12/33/3	13/27/5	8/28/3	22/36/7	55/123/18
Survival rate
5 year Recurrence free survival (%)	22	34	25	20	24
5 year over all survival (%)	34	43	52	60	46
Total	74	68	56	89	287

pm: pulmonary metastasis; EGFR = epidermal growth factor receptor