Persistent CXCR4 expression after preoperative chemoradiotherapy predicts early recurrence and poor prognosis in esophageal cancer

Table 1 Patient characteristics

Characteristics	n
Sex (M/F)	37 (30/7)
Mean age (yr)	60.32
Location of tumor
Cervical	1
Upper thoracic	6
Middle thoracic	19
Lower thoracic	11
T-classification
T3	14
T4	15
N-classification
N0	24
N1	13
M-classification
M0	28
M1	9
Disease stage (UICC TNM stage)
IIa	17
III	13
IVa	2
IVb	5

Table 2 Univariate analysis of prognostic factors for overall survival

Covariate		n	P
Age (yr)	< 70	31
	≥ 70	6	NS
Gender	Male	30
	Female	7	NS
CRT	Effective	28
	Not effective	9	0.00038b
Lymph node metastasis	Positive	13
	Negative	24	0.023a
Distant metastasis	Positive	14
	Negative	23	0.014a
Depth of tumor invasion	T3	23
	T4	14	NS
Tumor location1	Upper	14
	Lower	23	NS
CXCR4 expression	Positive	13
	Negative	24	0.0001b

¹Upper or lower: Above or below the tracheal bifurcation. NS: Not significant.

^aP < 0.05,

^bP < 0.01 comparison between two corresponding groups.