Table 2 Comparative analysis of oncologic features

Tumor size (cm)

1.5 (1.0–2.0)

2.0 (1.5–3.0)

2.0 (1.5–3.0)

 < 0.01

Location (%)

 < 0.01

 Upper

77 (55.4)

24 (22.2)

48 (28.2)

 Middle

10 (7.2)

25 (23.2)

28 (16.5)

 Lower

52 (37.4)

59 (54.6)

94 (55.3)

Infiltration (%)

 < 0.01

 Mucous

109 (78.4)

52 (48.1)

83 (48.8)

 Submucous

30 (21.6)

56 (51.9)

87 (51.2)

Pathology (%)

 < 0.01

 High

83 (59.7)

15 (13.8)

33 (19.4)

 Middle

43 (30.9)

48 (44.4)

59 (34.7)

 Lower

13 (9.4)

45 (41.8)

78 (45.9)

Lymph node

0

17 (14–21)

16 (12–20)^a

 < 0.01

Lymph node metastasis (%)

 < 0.01

 Yes

0 (0)

9 (8.3)

23 (13.5)^a

 No

139 (100)

99 (91.7)

147 (86.5)

Vascular invasion (%)

0.17*

 Yes

1 (0.7)

5 (4.6)

6 (3.5)

 No

138 (99.3)

103 (95.4)

164 (96.5)