Table I.

Comparison of pre-treatment clinicopathological characteristics according to CEA and CYFRA 21-1 levels.

		CEA, n (%)			CYFRA 21-1, n (%)
Patient characteristics	n (%)	<5 ng/ml	≥5 ng/ml	P-value	<3.3 ng/ml	≥3.3 ng/ml	P-value
Total	123 (100)	53 (43.1)	70 (56.9)		59 (48)	64 (52)
Age (years)
Median (range)	55 (34–88)			0.265			0.451
<65	81 (65.9)	32 (39.5)	49 (60.5)		41 (50.6)	40 (49.4)
≥65	42 (34.1)	21 (50.0)	21 (50.0)		18 (42.9)	24 (57.1)
Gender				<0.001			0.192
Male	70 (56.9)	40 (57.2)	30 (42.9)		30 (42.9)	40 (57.1)
Female	53 (43.1)	13 (24.5)	40 (75.5)		29 (54.7)	24 (45.3)
Histologic type				0.043			0.995
Adenocarcinoma	73 (59.3)	26 (35.6)	47 (64.4)		35 (47.9)	38 (52.1)
Non-adenocarcinoma	50 (40.7)	27 (54.0)	23 (46.0)		24 (48.0)	52 (52.0)
Clinical stage				0.439			0.628
IIIB	35 (18.5)	17 (48.6)	18 (51.4)		18 (51.4)	17 (48.6)
IV	88 (71.5)	36 (40.9)	52 (59.1)		41 (46.6)	47 (53.4)
Performance status				0.100			0.017
0–1	83 (67.5)	40 (48.2)	43 (51.8)		46 (55.4)	37 (44.6)
2	40 (32.5)	13 (32.5)	27 (67.5)		13 (32.5)	27 (67.5)
Smoking history				0.036			0.072
None	59 (47.5)	19 (32.8)	39 (67.2)		33 (56.9)	25 (43.1)
Current + former	64 (52.5)	33 (51.6)	31 (48.2)		26 (40.6)	38 (59.4)
No. of prior regimens				0.631			0.485
≤1	40 (32.5)	16 (40.0)	24 (60.0)		21 (52.5)	19 (47.5)
≥2	83 (67.5)	37 (44.6)	46 (55.4)		38 (45.8)	45 (54.2)
TKI				0.669			0.203
Gefitinib	72 (58.5)	29 (40.3)	43 (61.4)		37 (51.4)	35 (48.6)
Erlotinib	51 (41.5)	24 (47.1)	27 (52.9)		22 (43.1)	29 (56.9)
EGFR mutation (n=84)				0.418			0.789
Negative	47 (38.2)	19 (40.4)	28 (59.6)		23 (48.9)	24 (51.1)
Positive	37 (30.1)	14 (37.8)	23 (62.2)		19 (51.4)	18 (48.6)
Unknown	39 (31.7)	20 (51.3)	19 (48.7)		17 (43.6)	22 (56.4)

CEA, carcinoembryonic antigen; CYFRA 21-1, cytokeratin-19 fragments; TKI, tyrosine kinase inhibitor; EGFR, epidermal growth factor receptor