What types of early gastric cancer are indicated for endoscopic ultrasonography staging of invasion depth?

Table 3 Comparison of the invasion depth diagnosis between endoscopic ultrasonography and conventional endoscopy

	Clinical diagnosis	Histologic diagnosis		EUSdiagnosis		P2	Histologicdiagnosis		Accuracy	P (vs EUS)
		M/SM1	SM2	Overall accuracy	Accuracy1		M/SM1	SM2
Diagnosis	M/SM1	81	9	71.2	82.6		97	18	79.7	0.54
	SM2	14	28				13	25
Macroscopic type						0.30
I	M/SM1	-	-	-	-		5	1	88.9	-
	SM2	-	-				0	3
IIa/IIb	M/SM1	26	4	67.3	77.8		32	5	78.8	0.90
	SM2	6	9				6	9
IIc	M/SM1	55	5	80.4	85.1		60	12	79.3	0.32
	SM2	8	19				7	13
Location						0.55
Upper	M/SM1	21	2	74.4	80		24	4	80.0	> 0.99
	SM2	6	11				5	12
Middle	M/SM1	40	7	69.9	78.5		44	11	78.3	0.98
	SM2	7	11				4	10
Lower	M/SM1	19	2	62.2	85.2		29	3	82.1	> 0.99
	SM2	2	4				4	3
Histology						0.79
Diff.	M/SM1	71	10	70.4	83		77	12	80.5	0.63
	SM2	8	17				11	18
Undiff.	M/SM1	9	1	75.0	84		20	6	77.1	> 0.99
	SM2	4	12				2	7
Ulcer scar						< 0.0001
Positive	M/SM1	3	2	46.7	50		7	4	58.6	0.51
	SM2	12	11				8	10
Negative	M/SM1	77	7	75.6	89.4		90	14	84.7	0.29
	SM2	4	16				5	15
Indication for ER						< 0.0001
Absolute	M/SM1	37	-	80.4	97.4b		43	-	84.3f	0.07
	SM2	1	-				8	-
Expanded	M/SM1	28	-	75.7	87.5d		33	-	86.8h	> 0.99
	SM2	4	-				5	-
Non-indication	M/SM1	12	13	56.1	62.7bd		16	18	64.1fh	> 0.99
	SM2	9	25				5	25

Accuracy¹ was calculated with the exception of 21 inconclusive cases of EUS; P² indicates a significant difference in Accuracy¹.

^bP < 0.0001;

^dP = 0.02;

^fP = 0.02;

^hP = 0.01. EUS: Endoscopic ultrasonography; CE: conventional endoscopy; Diff: Differentiated-type; Undiff: Undifferentiated-type; ER: Endoscopic resection.