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

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.