Table 3.

Relationship between PTN levels and clinicopathological characteristics

Characteristics	Total	Serum PTN
		Higha	Lowb	P‐value
Age, y				0.472
≥60	70	38	32
<60	58	36	22
Gender				0.373
Male	60	32	28
Female	68	42	26
Smoking status				0.211
Non‐smoker	72	38	34
Smoker	56	36	20
Performance status				0.462
0‐1	80	44	36
2‐3	48	30	18
Disease stage				0.001*
Limited	58	24	34
Extended	70	50	20

PTN, pleiotrophin.

^aHigh group represents the levels of serum PTN ≥ 258.18 ng/mL.

^bLow group represents the levels of serum PTN < 258.18 ng/mL.

^*Statistically significant difference (P < 0.05)