Survival benefit of younger gastric cancer patients in China and the United States: A comparative study

Table 1 Demographic and clinicopathological characteristics of younger gastric cancer patients in China and the United States from 2000 to 2018

	China (n = 1159), n (%)		United States (n = 4939), n (%)		P value
Period of diagnosis					< 0.0001
1 (2000-2003)	194	16.7	972	19.7
2 (2004-2008)	237	20.5	1248	25.3
3 (2009-2013)	396	34.3	1280	25.9
4 (2014-2018)	332	28.6	1439	29.1
Race					< 0.0001
Chinese	1159	100.0	126	2.6
White			3405	69.9
Black			703	14.4
Others			640	13.1
Gender					0.135
Male	581	50.1	2599	52.6
Female	578	49.9	2340	47.4
Age (year), mean ± SD					0.005
	34		32.91
	5		5.38
Primary tumor location					< 0.0001
Proximal	176	16.3	1030	33.3
Distal	903	83.7	2067	66.7
Differentiation					< 0.0001
Well	9	1.2	211	7.5
Moderate	124	16.3	394	14.0
Poor/Undifferentiated	626	82.5	2214	78.5
Linitis plastica					0.070
Yes	29	2.6	57	1.7
No	1101	97.4	3279	98.3
Signet ring cell carcinoma					< 0.0001
Yes	426	52.9	1429	28.9
No	380	47.1	3510	71.1
Pathologic T-stage (AJCC 8th)					< 0.0001
T1	197	22.2	498	24.3
T2	97	10.9	266	13.0
T3	143	16.1	509	24.9
T4	452	50.8	773	37.8
Pathologic N-stage (AJCC 8th)					< 0.0001
N0	412	41.8	1137	49.9
N1	119	12.1	724	31.7
N2	162	16.4	232	10.2
N3	292	29.6	188	8.2
Pathologic M-stage					< 0.0001
M0	869	79.4	1268	45.9
M1	225	20.6	1492	54.1
pTNM stage (AJCC TNM 8th)					< 0.0001
I	222	21.2	649	20.3
II	169	16.1	377	11.7
III	433	41.3	498	15.5
IV	225	21.4	1687	52.5
Surgery					< 0.0001
Yes	869	75.1	2047	41.4
No	288	24.9	2892	58.6
Chemotherapy					< 0.0001
Yes	428	36.9	2991	60.6
No	731	63.1	1948	39.4
Lymphadenectomy					< 0.0001
Yes	780	67.4	941	19.1
No	377	32.6	3398	80.9
Lymphadenectomy with at least 15 lymph nodes					< 0.0001
Yes	606	52.4	524	10.6
No	551	47.6	4415	89.4
Number nodes examined (n), mean ± SD					< 0.0001
	25		18.9
	13		15.0
Number positive nodes (n), mean ± SD					< 0.0001
	6		7.4
	8		7.4

AJCC: American Joint Committee on Cancer; pTNM: Pathological Tumor-Node-Metastasis; SD: Standard deviation.