Plasma cell-free DNA methylation profile before afatinib treatment is associated with progression-free and overall survival of patients with epidermal growth factor receptor gene mutation-positive non-small cell lung cancer

Table 1 Clinicopathological characteristics of the initial and validation cohorts of the patients with non-small cell lung cancer

Clinicopathological parameters	Number of patients or median (range)		P^d
Clinicopathological parameters	Initial cohort (n = 60)	Second cohort (n = 43)	P^d
Age (years)	70 (42–86)	73 (50–88)	0.145
Less than 70	29	21	1.00
70 or more	31	22
Sex
Male	12	15	0.164
Female	48	28	0.164
Histological type
Adenocarcinoma	60	43
EGFR mutation
Exon 19 deletion	34	18	0.315
Exon 21 L858R	21	20
Others	5	5
Exon 18	2	1
Exon 20 insertion	1	2
Exon 20 T790M	0	1
Exon 21 L861Q	1	0
Exon 20 S768I + Exon 18 G719X	1	1
Performance status^a
0	26	26	0.111
1	34	17	0.111
Lymph node metastasis^b
Negative	51	38	0.351
Positive	9	3	0.351
Bone metastasis^b
Negative	57	37	0.437
Positive	3	4	0.437
Stage
III and IV	44	31	1.00
Post-surgical recurrence positive	16	12	1.00
Response^c
Complete response	3	1	0.812
Partial response	34	24
Stable disease	16	11
Progressive disease	2	0
Not applicable	5	5

^aAccording to the eastern cooperative oncology group performance status [23]
^bOnly patients for whom a diagnosis regarding metastasis to each organ has been made are described
^cAccording to the response evaluation criteria in solid tumors, version 1.1 [25]
^dWelch’s t-test for age (years) and Fisher’s exact-test for all other parameters

ISSN: 1868-7083