Table 3.

Association of PD-1 and PD-L1 expression with clinicopathological characteristics.

	PD-1						PD-L1
	Tumor-infiltrating lymphocytes			Tumor cells			Tumor-infiltrating lymphocytes			Tumor cells
	Low	High	p	Low	High	p	Negative	Positive	p	Negative	Positive	p
Age at surgery
<64	19	7	0.548	10	16	0.375	3	23	0.139	6	20	0.311
≥64	17	9		7	19		7	18		9	16
Sex
Male	18	11	0.209	8	21	0.378	4	24	0.291	7	21	0.446
Female	18	5		9	14		6	17		8	15
Localization of primary tumor
Colon	20	10	0.640	9	21	0.629	2	28	0.005	6	24	0.078
Rectum	16	6		8	14		8	13		9	12
UICC stage of primary tumor
I	2	1	0.422	1	2	0.868	1	1	0.735	1	1	0.866
II	9	4		4	9		2	11		3	10
III	18	6		9	15		5	19		7	17
IV	4	5		2	7		2	7		3	6
Unknown (n = 3)
Previous liver metastasis
No	25	11	0.960	10	26	0.257	6	29	0.512	10	25	0.846
Yes	11	5		7	9		4	12		5	11
Lung metastasis free survival
<36 mo	22	9	0.931	10	21	0.778	6	25	0.816	10	21	0.482
36–60 mo	6	2		3	5		2	6		3	5
60 mo	6	3		2	7		1	7		1	7
No. of pulmonary metastases
Singular	27	12	1.000	12	27	0.609	6	32	0.240	9	29	0.125
Multiple	9	4		5	8		4	9		6	7
Lymphatic vessel invasion
No	25	7	0.079	12	20	0.350	6	25	0.955	8	23	0.482
Yes	11	9		5	15		4	16		7	13
Chemotherapy before metastasectomy
No	6	4	0.482	3	7	0.840	1	9	0.393	2	8	0.466
Yes	30	12		14	28		9	32		13	28
Chemotherapy after metastasectomy
No	7	5	0.351	4	8	0.957	2	10	0.769	3	9	0.701
Yes	29	11		13	27		8	31		12	27