Table 2.

Clinical Characteristics of Patients with Lung Adenocarcinoma According to EGFR Copy Number Abnormalities

Characteristic	All Patients	Disomy	Low Polysomy	High Polysomy	Gene Amplified	P value*
	(N=65)	(N=17)	(N=16)	(N=23)	(N=9)
Age, years						0.657
Median (range)	59 (35-79)	62 (43-79)	62 (46-78)	56 (35-79)	66 (45-70)
Clinical stage						0.009
I	29 (45)	9 (53)	11 (69)	9 (39)	0 (0)
IIA	9 (14)	1 (6)	2 (13)	4 (17)	2 (22)
IIB	3 (5)	0 (0)	0 (0)	3 (13)	0 (0)
IIIA	15 (23)	5 (29)	2 (13)	3 (13)	5 (56)
IIIB	2 (3)	0 (0)	0 (0)	2 (9)	0 (0)
IV	7 (11)	2 (12)	1 (6)	2 (9)	2 (22)
Post-operative therapy†						0.508
None	3 (8)	1 (13)	1 (20)	1 (7)	0 (0)
Chemotherapy only	18 (50)	5 (63)	2 (40)	7 (50)	4 (44)
Radiot herapy only	6 (17)	0 (0)	0 (0)	3 (21)	3 (33)
Chemoradiation	9 (25)	2 (25)	2 (40)	3 (21)	2 (22)
TKI therapy†						0.558
No	33 (92)	8 (100)	5 (100)	11 (7)	9 (100)
Yes	3 (8)	0 (0)	0 (0)	3 (21)	0
EGFR mutation
Wildtype	13 (20)	6 (35)	3 (19)	4 (17)	0 (0)	0.185
Exon 19 deletion	39 (60)	8 (47)	10 (63)	12 (52)	9 (100)	0.009
Exon 21 (L858R)	15 (23)	3 (18)	5 (31)	6 (26)	1 (11)	0.672
Exons 18 or 20 insertion	3 (5)	0 (0)	1 (6)	2 (9)	0 (0)	1
T790M	1 (2)	0 (0)	0 (0)	0 (0)	0 (0)	1
Dominant histology
Acinar	17 (26)	3 (18)	5 (31)	8 (35)	1 (11)	0.426
Bronchioloalveolar	7 (11)	5 (30)	1 (6)	1 (4)	0	1
Papillary	29 (45)	7 (41)	8 (50)	11 (48)	3 (33)	0.72
Solid	12 (18)	2 (12)	2 (13)	3 (13)	5 (56)	0.008
EGFR protein expression						<0.001
0	36 (55)	13 (76)	9 (56)	13 (56)	1 (11)
1	10 (15)	3 (18)	4 (25)	3 (13)	0
2	4 (6)	1 (6)	0 (0)	2 (9)	1 (11)
3	15 (23)	0 (0)	3 (19)	5 (22)	7 (78)

^*P-value is based on the comparison between patients with EGFR amplification and all other patients.

^†Stage II-IV only