Table IV. Relations between PE levels of three marker candidates and clinical characteristics in new independent cohort (n = 117) with PE.

Variables	No.	MET (ng/ml)a	p valueb	PTPRF (ng/ml)	p valueb	DPP4 (ng/ml)	p valueb
Lung disease
TB, PN	30	144.78 ± 41.07	<0.001c	72.23 ± 26.32	<0.001c	195.71 ± 105.62	0.114c
PMPE	28	156.05 ± 86.87	<0.001d	92.27 ± 74.37	<0.001d	167.73 ± 83.31	0.003d
MPE	59	483.58 ± 527.98		174.23 ± 163.05		293.26 ± 421.60
Lung cancer histology
Adenocarcinoma	53	516.63 ± 546.64	<0.001	174.66 ± 165.95	0.02	308.47 ± 442.20	<0.001
Nonadenocarcinoma	34	168.57 ± 112.62		106.05 ± 93.62		166.17 ± 79.53

^a The data are presented as the mean ± S.D.

^b Mann-Whitney U test.

^c The p value presents the difference between NSCLC-MPE and benign diseases (TB and PN).

^d The p value presents the difference between NSCLC-MPE and NSCLC-PMPE.