Polymorphisms of the DNA Methyltransferase 1 Gene Predict Survival of Gastric Cancer Patients Receiving Tumorectomy

Table 1

Characteristics and clinical features of gastric cancer patients.

Variables	Number of patients	Number of deaths	Mean OS (months)	Log-rank	HR (95% CI)
All	422	195	54.5
Gender
Female	117 (27.7)	45	57.8	0.044	1.00
Male	305 (72.3)	152	48.8		1.41 (1.01–1.96)
Age
≤60	209 (49.5)	91	52.5	0.218	1.00
>60	213 (50.5)	106	50.2		1.19 (0.90–1.58)
Tumor size
≤5 cm	231 (55.8)	75	62.6	<0.001	1.00
>5 cm	183 (44.2)	116	39.5		2.63 (1.96–3.52)
Pathological type
Tubular adenocarcinoma	368 (87.4)	170	52.2	0.167	1.00
Signet ring cell carcinoma	22 (5.2)	8	49.1		0.75 (0.37–1.53)
Others	31 (7.4)	19	38.8		1.49 (0.93–2.40)
Differentiation
Well to moderate	155 (37.1)	70	55.7	0.161	1.00
Poor	263 (62.9)	124	49.4		1.23 (0.92–1.65)
Depth of invasion
T1/T2	97 (23.0)	13	74.2	<0.001	1.00
T3/T4	322 (77.0)	182	44.8		5.96 (3.39–10.46)
Lymph metastasis
N0	119 (29.1)	15	75.5	<0.001	1.00
N1/N2/N3	300 (70.9)	180	42.0		7.16 (4.22–12.14)
Distant metastasis
M0	392 (92.9)	174	53.9	<0.001	1.00
M1	30 (7.1)	23	25.4		2.70 (1.75–4.18)
TNM stage
I/II	240 (56.9)	57	69.5	<0.001	1.00
III/IV	182 (43.1)	140	28.6		5.97 (4.37–8.16)
Lymph-vascular invasion
Absent	112 (26.5)	20	73.4	<0.001	1.00
Present	305 (73.5)	173	43.9		4.39 (2.76–6.99)
Neural invasion
Absent	199 (47.2)	65	63.0	<0.001	1.00
Present	218 (52.8)	128	42.4		2.42 (1.80–3.27)
Radical surgery
Yes	407 (96.4)	182	53.6	<0.001	1.00
No	15 (3.6)	15	10.8		5.61 (3.28–9.60)
Chemotherapy
None	284 (67.3)	132	51.7	0.157	1.00
XELOX	29 (6.9)	9	62.8		0.55 (0.28–1.08)
FOLFOX-4	77 (18.2)	36	51.3		0.98 (0.68–1.41)
Others	32 (7.6)	20	39.6		1.34 (0.84–2.15)

OS: overall survival; HR: hazard ratio; CI: confidence interval.
Fifteen patients received palliative surgery.
XELOX (capecitabine and oxaliplatin); FOLFOX-4 (5-fluorouracil, leucovorin, and oxaliplatin); other chemotherapies included 5-fluorouracil; Xeloda alone; paclitaxel plus leucovorin and tegafurum; LV5-FU2 (leucovorin plus 5-fluorouracil); and FOLFIRI (irinotecan, 5-fluorouracil, and leucovorin).