Endoscopic submucosal dissection for undifferentiated-type early gastric cancer: Do we have enough data to support this?

Table 2 Proposed criteria for endoscopic resection of undifferentiated type early gastric cancer

Study	Year	Country	No. of patients with UD-EGC	No. of patients with PD/SRC/MC	LNM in UD-EGC, n (%)	LNM in proposed criteria	Risk factors related to LNM in UD-EGC	Proposed criteria of ER for UD-EGC
								Size, mm	Depth of invasion	Ulcer	LVI
Tong et al[53]	2011	China	193	81/102/7/31	46 (23.8)	0/72	Size, depth of invasion, LVI, Histologic type	NS or ≤ 20	M or SM	NS	No
Kim et al[54]	2011	South Korea	707	288/419/0	65 (9.2)	0/101	Size, depth of invasion, LVI, Age2	153	M	NS	No
Li et al[55]	2010	China	108	85/16/7	16 (14.8)	0/25	Size, depth of invasion, LVI	20	M	NS	No
Park et al[56]	2009	South Korea	215	Only SRC	17 (7.9)	0/57	Depth of invasion, LVI	25	SM2	NS	No
Kunisaki et al[57]	2009	Japan	573	182/378/13	74 (12.9)	0/85	Size, depth of invasion, LVI	20	M	NS	No
Hirasawa et al[26]	2009	Japan	3843	NA	504 (13.1)	0/310	Size, depth of invasion, LVI	20	M	No	No
Hanaoka et al[58]	2009	Japan	143	NA	35 (24.5)	0/41	Size, depth of invasion, LVI, Histologic type	30	≤ 500 μm4	NS	No5
Ye et al[59]	2008	South Korea	591	266/316/9	79 (13.4)	0/119	Size, depth of invasion, LVI	25	M	NS	No
Park et al[60]	2008	South Korea	234	Only PD	25 (21.6)	0/56	Size, depth of invasion, LVI	15	M or ≤ 500 μm	NS	No
Li et al[61]	2008	China	85	Only PD	12 (14.1)	0/25	Size, depth of invasion, LVI	20	M	NS	No
Li et al[62]	2008	South Korea	646	307/330/9	61 (9.4)	1/201	Size, depth of invasion, LVI	20	M	NS	No
Ha et al[63]	2008	South Korea	641	248/388/5	100 (15.6)	0/77	Size, depth of invasion, LVI, histologic type	20	M	NS	No
Hyung et al[64]	2004	South Korea	289	NA	43 (14.9)	NA	Size, depth of invasion, LVI, histologic type	15	M	NS	No
Abe et al[65]	2004	Japan	175	68/104/3	32 (18.3)	0/6	Size, LVI	10	M	NS	No
Gotoda et al[23]	2000	Japan	2341	NA	243 (10.4)	0/141	Size, depth of invasion, LVI, histologic type, ulcer, macroscopic type	20	M	No	No

¹Three patients had EGCs with histology of undifferentiated adenocarcinoma;

²Young age less than 45 years was related to the lymph node metastasis of only poorly-differentiated carcinoma;

³Size criteria were ≤ 25 mm in poorly-differentiated adenocarcinomas and ≤ 15 mm in signet-ring cell carcinomas, respectively;

⁴The depth of invasion in proposed criteria was ≤ 500 μm or no more from the lower margin of the muscularis mucosae;

⁵Hanaoka et al also suggested the proportion of undifferentiated components < 50% as one of criteria. UD-EGC: Undifferentiated type early gastric cancer; PD: Poorly-differentiated adenocarcinoma; SRC: Signet-ring cell carcinoma; MC: Mucinous carcinoma; LNM: Lymph node metastasis; ER: Endoscopic resection; LVI: Lymphovascular invasion; M: Mucosa; SM: Submucosa; NS: Not significant; NA: Not available.