Table 3 Anatomical site, macroscopic appearance, histopathological type/grade and metastasis at the time of diagnosis

Anatomical site

Upper third esophagus

34

10.4

Middle third esophagus

192

58.5

Lower third esophagus

90

27.4

Not documented

12

3.7

Tumor length

≤ 5 cm

132

40.2

>5 cm

185

52.4

Not documented

11

3.4

Gross/macroscopic appearance

Ulcerative

132

40.2

Infiltrative

106

32.3

Stricture

12

3.7

Polypoid

7

2.1

Fungoid

6

1.8

Mixed

41

12.5

Not documented

24

7.3

Histopathological type

Squamous cell carcinoma

315

96.0

Adenocarcinoma

13

4.0

Tumor grading

Well-differentiated

104

31.7

Moderately differentiated

184

56.1

Poorly differentiated

40

12.2

Tumor staging

I and II

2

0.6

III and IV

102

31.1

Not documented

224

68.3

Distant metastasis

Yes

142

43.3

No

104

31.7

Not documented

82

25.0