Table 1. Clinical and molecular characteristics of included SCLC patients.

	Total (n = 80)	CTC counts (/3 mL)	P value	CTC positive (n = 67)	CTC negative (n = 13)	P value
Age (years)
Median	62 (41–81)			62 (41–81)	60 (49–75)
< 65	51	16.9	0.310	41	10	0.794
≥ 65	29	14.7		24	5
Gender
Male	69	16.2	0.880	58	11	0.800
Female	11	15.7		9	2
Smoking history
Never-smoker	30	16.4	0.871	24	6	0.481
Former/current smoker	50	16.0		43	7
Metastases
Yes	40	18.0	0.113	35	5	0.363
No	40	14.3		32	8
Stage
I-II	4	14.0	0.523	3	1	0.181
III-IV	76	16.2		64	12
VALG stage
Limited stage	3	13.7	0.414	2	1	0.984
Extensive stage	77	16.4		65	12
Regimen
Etoposide+cisplatin	60	15.6	0.650	48	12	0.835
Etoposide+carboplatin	16	18.3		15	1
Etoposide	4	15.5		4	0