Subclassification scheme for adenocarcinomas of the esophagogastric junction and prognostic analysis based on clinicopathological features

Table 1 Patient characteristics, mean ± SD

Characteristic	Variables	n	%
Age (year)	62.4 ± 8.5
	≤ 65	95	62.1
	> 65	58	37.9
Sex	Male	126	82.4
	Female	27	17.6
Maximal tumor size (mm)	44.2 ± 15.5
	≤ 40 mm	86	56.2
	> 40 mm	67	43.8
Esophageal invasion length (mm)	13.4 ± 13.8
	< 20 mm	101	66.0
	≥ 20 mm	52	34.0
Siewert classification	I	11	7.2
	II	142	92.8
Nishi classification	E = G	5	3.3
	GE	74	48.4
	EG	7	4.6
	Not applicable	67	43.8
This classification	E	22	14.4
	Eg	31	20.3
	Ge	100	65.4
Surgical approaches	Transthoracic approach	27	17.6
	Transabdominal hiatal approach	126	82.4
Extent of surgical resection	Subtotal esophagectomy with partial gastrectomy	27	17.6
	Proximal gastrectomy with partial esophagectomy	34	22.2
	Total gastrectomy with partial esophagectomy	92	60.1
Histologic type	Adenocarcinoma	145	94.8
	Mixed adenocarcinoma	8	5.2
Histological grade	Well-moderately differentiated	72	47.1
	Moderately-poorly differentiated	80	52.3
Lauren type	Intestinal type	56	36.6
	Diffuse type	44	28.8
	Mixed type	51	33.3
Preoperative chemotherapy	No	104	68.0
	Yes	49	32.0
Vessel invasion	No	128	83.7
	Yes	25	16.3
Perineural invasion	No	73	47.7
	Yes	80	52.3
Pathological depth of tumor invasion	T1-2	48	31.4
	T3-4	105	68.6
Lymph node metastasis	N0	73	47.7
	N1-3	80	52.3
Distant metastasis	pM0	147	96.1
	pM1	6	3.9
TNM-GC staging system	IA	24	15.7
	IB	16	10.5
	IIA	8	5.2
	IIB	33	21.6
	IIIA	30	19.6
	IIIB	28	18.3
	IIIC	8	5.2
	IV	6	3.9
TNM-EC staging system	IA	5	3.3
	IB	17	11.1
	IC	16	10.5
	IIA	1	0.7
	IIB	4	2.6
	IIIA	5	3.3
	IIIB	49	32.0
	IIIC/IVA	50	32.7
	IVB	6	3.9

TNM: Tumor node metastasis; GC: Gastric cancer; EC: Esophageal cancer.