Table 4.

Outcomes depending on the depth of mural invasion of the 56 resected oesophageal early squamous cell carcinomas (ESCCs).

Depth of invasion	Low risk group : m1–2 (n = 33)	Intermediate risk group: m3, superficial sm (n = 16)	High risk group: > superficial sm (n = 7)	p a
Female sex (n = 13)	7 (21%)	2 (12%)	4 (57%)	0.11
Age <60 years (n = 25)	16 (48%)	7 (44%)	2 (28%)	0.63
Piecemeal resection (n = 1)	0 (0%)	0 (0%)	1 (14%)	0.125
Moderately or poorly differentiated cancer (n = 11)	0 (0%)	7 (44%)	4 (57%)	<0.001
Lymphatic or vascular invasion (n = 8)	1(3%)	3 (19%)	4 (57%)	0.001
Positive vertical margin (R1) (n = 4)	0 (0%)	0 (0%)	4 (43%)	0.001
Local recurrence (n = 5)	3 (9%)	2 (12%)	0 (0%)	0.99
Cancer related death (n = 2)	0 (0%)	2 (4%)b	0 (0%)	0.17

Superficial sm: tumour infiltration of the submucosa below 200 µm.

Deep sm: tumour infiltration of the submucosa beyond 200 µm.

^aUnivariate analysis; ^bboth cases were poorly differentiated tumours.