Clinical epidemiology of gastric cancer in Hehuang valley of China: A 10-year epidemiological study of gastric cancer

Table 1 Demographic features of gastric cancer patients in Hehuang valley n (%)

		Previous 5 yr group (n = 985)	Past 5 yr group (n = 1394)	P value
Sex	Male	785 (79.7)	1083 (77.7)	0.241
	Female	200 (20.3)	311 (2.3)
Age (yr)	18-44	190 (19.3)	390 (28)	0.000
	45-85	795 (80.7)	1004 (72)
Family history	Positive	437 (44.4)	813 (58.3)	0.000
	Negative	548 (55.6)	581 (41.7)
Nationality	Muslims	576 (58.5)	792 (56.8)	0.685
	Tibetan	18 (1.8)	24 (1.7)
	Han	391 (39.7)	578 (41.5)

The native Hui and Salar in Qinghai were also included in Muslims. The Hehuang valley, an agricultural area, is located in the eastern Qinghai Province, China.

Table 2 Clinical data of patients in past and previous 5-year groups n (%)

	Past 5 yr group	Previous 5 yr group	P value		Past 5 yr group	Previous 5 yr group	P value
	(n = 1394)	(n = 985)			(n = 1394)	(n = 985)
Tumor location			< 0.05	Perineural invasion			< 0.05
Upper (U)	467 (33.5)	266 (27.0)		Positive	685 (49.1)	389 (39.5)
Middle (M)	142 (10.2)	94 (9.5)		Negative	709 (50.9)	596 (60.5)
Lower (L)	705 (50.6)	530 (53.8)		Vascular invasion			< 0.05
UML	80 (5.7)	95 (9.6)		Positive	671 (48.1)	375 (38.1)
Tumor classification				Negative	723 (51.9)	610 (61.9)
Early stage1			> 0.05	Her-2 Expression			> 0.05
Type I	3 (0.2)	1 (0.1)		Positive	104 (7.5)	62 (6.3)
Type IIa	2 (0.1)	2 (0.2)		Negative	1290 (92.5)	923 (93.7)
Type IIb	5 (0.4)	5 (0.5)		H. pylori infection			< 0.05
Type IIc	3 (2.0)	3 (0.3)		Positive	610 (43.8)	357 (36.2)
Type III	8 (5.7)	4 (0.4)		Negative	784 (56.2)	628 (63.8)
Advanced stage2			< 0.05	ER Expression			< 0.05
Type I	201 (14.4)	199 (20.2)		Positive	365 (26.2)	45 (4.6)
Type II	365 (26.2)	206 (20.9)		Negative	1029 (73.8)	940 (95.4)
Type III	520 (37.3)	375 (38.1)		PR Expression			< 0.05
Type IV	288 (20.7)	190 (19.3)		Positive	340 (24.4)	39 (4.0)
Pathological type			< 0.05	Negative	1054 (75.6)	946 (96.0)
Adenocarcinoma	1335 (95.8)	902 (91.6)		Lymph node metastasis			< 0.05
Squamous cell carcinoma	38 (2.7)	16 (1.6)		Positive	1250 (90.0)	850 (86.3)
Signet-ring cell carcinoma	9 (0.6)	14 (1.4)		Negative	144 (10.3)	135 (13.7)
Other	12 (0.9)	53 (5.4)
Histological type			< 0.05	Lauren classification			> 0.05
Well-differentiated type	264 (19.0)	157 (15.9)		Intestinal	890 (63.8)	682 (69.2)
Moderately differentiated type	907 (65.1)	728 (73.9)		Nonintestinal	504 (36.2)	303 (30.8)
Poorly/undifferentiated type	223 (16.0)	100 (10.2)

¹Histological type was based on the criteria of World Health Organization;

²Advanced stage classification was in accordance with Borrmann type; Her-2: Human epidermal growth factor receptor-2; H. pylori: Helicobacter pylori; ER: Estrogen receptor; PR: Progesterone receptor. P < 0.05, the previous vs the past year group.

Table 3 Gastric cancer characteristics of different ethnic groups in the Hehuang valley n (%)

	Past 5 yr group			P value	Previous 5 yr group			P value
	Muslims (n = 792)	Tibetan (n = 24)	Han (n = 578)		Muslims (n = 576)	Tibetan (n = 18)	Han (n = 391)
Age (yr)				0.511				0.268
20-44	110 (13.9)	4 (16.7)	93 (16.1)		72 (12.5)	3 (16.7)	63 (16.1)
45-85	682 (86.1)	20 (83.3)	485 (84.0)		504 (87.2)	15 (83.3)	328 (83.9)
Sex				0.281				0.310
Male	645 (81.4)	18 (75.0)	486 (84.0)		485 (84.2)	16 (88.9)	316 (80.8)
Female	147 (18.6)	6 (25.0)	92 (20.0)		91 (15.8)	2 (11.1)	75 (19.2)
H. pylori infection				0.002				< 0.001
Positive	340 (43.0)	19 (79.2)	251 (43.4)		182 (31.6)	12 (66.7)	163 (41.7)
Negative	452 (57.1)	5 (20.8)	327 (56.6)		394 (68.4)	6 (33.3)	228 (58.3)
Lauren classification				0.045				< 0.001
Intestinal	527 (66.5)	16 (66.7)	347 (60.0)		427 (74.1)	12 (66.7)	243 (62.1)
Nonintestinal	265 (33.5)	8 (33.3)	231 (40.0)		149 (25.9)	6 (33.3)	148 (37.9)
Tumor location				0.011				0.005
Upper (U)	260 (32.8)	15 (62.5)	192 (33.2)		143 (24.9)	2 (11.1)	121 (31.0)
Middle (M)	86 (10.9)	3 (12.5)	53 (9.2)		45 (7.8)	1 (5.6)	48 (12.3)
Lower (L)	414 (52.3)	4 (16.7)	287 (50.0)		336 (58.3)	11 (61.1)	183 (46.8)
UML	32 (4.0)	2 (8.3)	46 (8.0)		52 (9.0)	4 (22.2)	39 (10.0)

The native Hui and Salar in Qinghai were also included in Muslims; the Hehuang valley, an agricultural area, is located in the eastern Qinghai province, China; P < 0.05, the past 5 years group vs the previous 5 years group. H. pylori: Helicobacter pylori.

Table 4 Clinical data of patients of different ages and genders n (%)

	Gastric cancer in youth	Gastric cancer in the elderly	P value	Male	Female	P value
	(n = 580)	(n = 1799)		(n = 1868)	(n = 511)
Histological type			< 0.001			< 0.001
Well-differentiated type	22 (3.8)	399 (22.2)		298 (16.0)	123 (24.0)
Moderately differentiated type	433 (74.7)	1202 (66.8)		1289 (69.0)	346 (67.7)
Poorly/undifferentiated type	125 (21.6)	198 (11.0)		281 (15.0)	42 (8.2)
Pathological type			< 0.001			0.050
Adenocarcinoma	520 (89.7)	1717 (95.4)		1747 (93.5)	490 (95.9)
Squamous cell carcinoma	29 (5.0)	25 (1.4)		42 (2.2)	12 (2.3)
Signet-ring cell carcinoma	17 (2.9)	6 (0.3)		19 (1.0)	4 (0.79)
Other	14 (2.4)	51 (2.8)		60 (3.2)	5 (0.98)
Her-2 Expression			< 0.001			< 0.001
Positive	95 (16.4)	71 (3.9)		68 (3.6)	98 (19.2)
Negative	485 (83.6)	1728 (96.1)		1800 (96.4)	413 (80.8)
Early stage1			0.681			0.026
	0 (0.0)	4 (0.2)		4 (0.2)	0 (0.0)
Type IIa	0 (0.0)	4 (0.2)		3 (0.2)	1 (0.2)
Type IIb	0 (0.0)	9 (0.5)		7 (0.4)	2 (0.4)
Type IIc	1 (0.2)	5 (0.3)		4 (0.2)	2 (0.4)
Type III	2 (0.3)	10 (0.6)		5 (0.3)	7 (1.3)
Advanced stage2			< 0.001			< 0.001
Type I	44 (7.6)	356 (19.8)		255 (13.7)	145 (28.4)
Type II	60 (10.3)	511 (28.4)		484 (25.9)	87 (17.0)
Type III	317 (23.6)	578 (32.1)		679 (36.3)	216 (42.3)
Type IV	156 (26.9)	322 (17.9)		427 (22.9)	51 (10.0)
H. pylori infection			< 0.001			0.816
Positive	390 (67.2)	577 (32.1)		757 (40.5)	210 (41.1)
Negative	190 (32.8)	1222 (67.9)		1111 (59.5)	301 (59.0)
Lauren classification			< 0.001
Intestinal	124 (21.4)	1448 (80.5)		-	-
Nonintestinal	456 (78.6)	351 (19.5)		-	-

¹Early stage classification was in accordance with the Japanese Society of Gastroenterological Endoscopy;

²Advanced stage classification was in accordance with Borrmann type. Gastric cancer in youths refers to patients between 18 and 45 years old; Gastric cancer in the elderly refers patients between 45 and 85 years old. Her-2: Human epidermal growth factor receptor-2; H. pylori: Helicobacter pylori.

Table 5 Comparison of dietary habits in gastric cancer patients and healthy residents in Hehuang valley n (%)

	Male		P value	Odds ratio (95%CI)	Female		P value	Odds ratio (95%CI)
	Gastric cancer patients	Healthy residents			Gastric cancer patients	Healthy residents
	(n = 1868)	(n = 1810)			(n = 511)	(n = 500)
Smoking	326 (17.5)	298 (16.5)	0.425	1.73 (0.903-1.274)	2 (0.4)	3 (0.6)	0.636	0.651 (0.108-3.912)
Drinking alcohol	475 (25.4)	460 (25.4)	0.963	1.004 (0.865-1.164)	5 (1.0)	6 (1.2)	0.734	0.814 (0.247-2.683)
Rapid eating	1492 (79.9)	320 (17.7)	< 0.001	18.476 (15.659-21.801)	12 (2.3)	10 (2.0)	0.704	1.178 (0.504-2.753)
Irregular dinner-time	285 (15.3)	237 (13.1)	0.600	1.195 (0.992-1.439)	15 (3.0)	17 (3.4)	0.673	0.859 (0.424-1.740)
Regular consumption of overnight food	153 (8.2)	142 (7.8)	0.700	1.048 (0.826-1.330)	36 (7.0)	28 (5.6)	0.345	1.278 (0.767-2.128)
Regular consumption of preserved food	269 (14.4)	254 (14.0)	0.750	1.031 (0.856-1.240)	164 (32.1)	105 (21.0)	< 0.001	1.778 (1.338-2.363)
Regular consumption of fried or grilled food	1320 (70.7)	410 (22.7)	< 0.001	8.225 (7.090-9.541)	350 (68.5)	62 (12.4)	< 0.001	15.358 (11.097-21.253)
Consumption of high-salt, high-fat and spicy food	1437 (76.9)	35 (1.9)	< 0.001	169.807 (118.983-240.290)	368 (72.0)	122 (24.4)	< 0.001	7.973 (0.602-10.560)
Drinking strong boiled brick-tea1	1395 (74.7)	260 (14.4)	< 0.001	17.582 (14.867-20.793)	375 (73.4)	120 (24.0)	< 0.001	8.732 (6.573-11.598)
Eating too hot or too cold food	1205 (64.5)	45 (2.5)	< 0.001	71.286 (52.249-97.260)	45 (8.8)	32 (0.6)	0.149	1.412 (0.882-2.262)

¹Boiled brick-tea is a pressed dark tea popular in Northwestern China.