Table 2 Clinicopathological features of cN0 esophageal cancer patients

Gender

0.712

 Female

9

20

 Male

51

133

Age at surgery

67 (51–85)

66 (39–81)

0.890

Tumor location

0.338

 Upper

4

18

 Middle

33

79

 Lower

23

56

Tumor size (mm)

40 (10–95)

35 (10–106)

0.146

Tumor depth (pT)

< 0.0001*

 T1

29

123

 T2

7

10

 T3

22

18

 T4a

2

0

 T4b

0

2

Lymph node metastasis (pN)

< 0.0001*

 N0

0

152

 N1

45

0

 N2

12

1

 N3

3

0

Pathological stage

< 0.0001*

 IA

1

109

 IB

0

23

 IIA

0

18

 IIB

27

0

 IIIA

23

1

 IIIB

4

0

 IIIC

5

2

Tumor histology

0.032*

 Squamous cell carcinoma

49

141

 Adenocarcinoma

5

6

 Other

6

6

Tumor differentiation of SCC

 G1

11

17

0.005*

 G2

23

101

 G3

15

21

 N/A

0

2

Prognosis

 Alive

40

124

0.017*

 Deceased from esophageal ca.

10

7

 Deceased from other ca.

0

4

 Deceased from other diseases

10

18