Table 1. Clinico-pathological characteristics of esophageal cancer patients for immunohistochemical investigation.

	No. of patients		p value
	IHC-PD-L1(−)	IHC-PD-L1(+)
patients	88	74
Age
>=55.3y/0	43	39	0.588
<55.3y/o	45	35
Location
Upper third	18	18	0.174
Middle third	55	36
Lower third	15	20
Tumor stage			0.004*
<=T3	63	37
T4	25	37
LN metastasis			0.012*
negative	28	11
positive	60	63
IL-6 staining			<0.0001*
negative	60	19
positive	28	55
Response to Neoadjuvant Tx			<0.0001*
Response	75	40
Non- response	13	34
Surgery s/p Neoadjuvant Tx			0.228
Yes	29	18
No	59	56
Local-regional Recurrence/persistent			0.001*
No	40	16
Yes	48	58
Distant metastasis			0.208
negative	55	39
positive	33	35

Abbreviations: Neoadjuvant Tx = neoadjuvant chemoradiotherapy.