Table 1.

Socio-demographic and tumour-related characteristics of EBV- positive and EBV-negative GC patients

	Total %	EBV-positive gastric carcinomas (n=26)	EBV-negative gastric carcinomas (n=276)	p value (refers to all the group)
		N	N
Sex
female	39.4	4	115
male	60.6	22	161	0.01
Age
Mean ± SD	63.6 ±11.54	63.8 ± 11.9	62.1 ± 11.5	0.86
Age ≤ 65 years	53.0	14	146
Age > 65 years	47.0	12	130	0.54
Smoking status a
never	43.4	8	123
current	25.8	8	70
former	21.2	7	57	0.60
BMI b
< 18.5	3.6	1	10
18.5 – 24.9	45.7	12	126
≥ 25	42.4	10	118	0.92
Previous history of other cancers
no	94.7	26	260
yes	5.3	0	16	0.37
Stage c
0	0.3	0	1
I	22.2	4	63
II	23.2	8	62
III	36.1	7	102
IV	14.9	7	38	0.33
Tumour location
Proximal	47.7	13	131
Distal	18.9	2	55
Overlapping/unspecified	33.4	11	90	0.27
Local recurrence
no	95.4	25	263	0.84
Lauren’s classification d
Intestinal	49.0	14	134
Diffuse	31.5	7	88
Mixed	14.5	4	40	0.97
Grade e
G1 and G2	26.4	8	72
G3	73.2	18	203	0.51
Intestinal metaplasia in adjacent tissues
no	74.2	19	205
yes	25.8	7	71	0.52
Atrophy in adjacent tissues
no	42.7	11	118
yes	57.3	15	158	0.56

EBV, Epstein-Barr virus.

^a.smoking status: unknown – 9.6% of all patients, 3 patients in EBV positive and 26 EBV negative group;

^b.BMI: unknown – 8.3% of all patients, 3 patients in EBV positive and 22 EBV negative group;

^c.stage: unknown – 3.3% of all patients, 0 in EBV positive and 10 EBV negative group;

^d.Lauren’s classification: indeterminate – 5% of all patients, 1 in EBV positive and 14 EBV negative group;

^e.grade: unknown - 0.4% of all patients, 0 in EBV positive and 1 EBV negative group.