Stratifying the risk of lymph node metastasis in undifferentiated-type early gastric cancer

Table 4 Studies for factors and their conditions required for low incidence of lymph node metastasis in patients with undifferentiated-type early gastric cancer

Ref.	Country	Condition for low LNM incidence						Pts in the condition	Pts with LNM	LNM (95%CI)
		Size (cm)	Depth	LI	VI	UL	Other
Yamao et al[8]	Japan	< 3	m	LI(-)	VI(-)	UL(-)		277	1	0.36% (0.06-2.02)
Gotoda et al[1]	Japan	≤ 2	m	LI(-)	VI(-)	UL(-)		141	0	0% (0-2.6)
Ye et al[9]	South Korea	< 2.5	m	LI(-)	NS	NS		131	0	0% (0-2.28)
			sm1
Li et al[10]	China	≤ 2	m	LI(-)	VI(-)	NT		201	1	0.5% (0.08-2.76)
Ha et al[11]	South Korea	< 2	m	LI(-)	NT	NT	Sig	77	0	0% (0-4.75)
Hirasawa et al[2]	Japan	≤ 2	m	LI(-)	VI(-)	UL(-)		310	0	0% (0-0.96)
Kunisaki et al[12]	Japan	≤ 2	m	LI(-)	VI(-)		Por	84	0	0% (0-4.37)
1Lee et al[13]	South Korea	≤ 2	m	LI(-)	NS	NS	Male	124	4	3.2% (1.26-8.00)
This study	Japan	≤ 2	m	LI(-)	NS	NS		161	0	0% (0-2.33)

¹Study for patients with poorly differentiated adenocarcinoma. LNM: Lymph node metastasis; m: Mucosal cancer; sm: Submucosal cancer; Pts: Patients; LVI: Lymph-vascular involvement; LI: Lymphatic involvement; VI: Venous involvement; UL: Ulceration; NS: Not significant; NT: Not tested.