Trends, clinicopathological features, and prognosis of 687 cases of early-onset gastric cancer: A single-center, retrospective study

Table 1 The clinicopathological features of 687 cases of early-onset gastric cancer

Variables	n (%)
Gender
Male	321 (46.72)
Female	366 (53.28)
Age
≤ 24	16 (2.33)
25-35	164 (23.87)
≥ 36	507 (73.80)
Smoking history
Yes	138 (20.09)
No	549 (79.91)
Alcohol history
Yes	111 (16.16)
No	576 (83.84)
Stomach disease history
Yes	15 (2.18)
No	672 (97.82)
Family history
Yes	18 (2.62)
No	669 (97.38)
BMI
< 18.5	142 (21.10)
18.5-24.9	439 (65.23)
25.0-29.9	84 (12.48)
≥ 30	8 (1.19)
Unknown	14
Health check-up
Yes	6 (0.87)
No	681 (99.13)
H. pylori infection
Yes	213 (35.92)
No	380 (64.02)
Unknown	94
Tumor location
Fundus cardia	31 (4.51)
Body	466 (67.83)
Antrum pylorus	184 (26.78)
Others	7 (1.02)
Lauren classification
Intestinal	59 (8.81)
Diffuse	604 (90.15)
Mixed	7 (1.04)
Unknown	17
HER-2
Positive	28 (4.94)
Negative	539 (95.06)
Unknown	120
MMR
dMMR	12 (2.27)
pMMR	516 (97.73)
Unknown	159
PD-L1
CPS ≥ 5	54 (26.73)
CPS < 5	148 (73.27)
Unknown	485
Radical surgery
Yes	484 (70.45)
No	203 (29.55)
TNM stage
I	97 (14.18)
II	103 (15.06)
III	271 (39.62)
IV	213 (31.14)
Unknown	3
Metastatic site
Lymph node	101 (14.70)
Ovary1	41 (11.20)
Peritoneum/malignant ascites	58 (8.44)
Liver	40 (5.82)
Bone	19 (2.77)
Others	8 (1.16)

¹The formula for calculating ovarian metastasis is based on female patients, not the entire group of patients.

Unknown patients are not included in the total number. BMI: Body mass index; H. pylori: Helicobacter pylori; HER-2: Human epidermal growth factor receptor 2; MMR: Mismatch repair; dMMR: Deficient mismatch repair; pMMR: Proficient mismatch repair; PD-L1: Programmed cell death ligand 1; CPS: Combined positive score; TNM: Tumor-node-metastasis.

Table 2 The proportion of early-onset gastric cancer among gastric cancer each year

Year	EOGC (n)	LOGC (n)	GC (n)	The proportion of EOGC/GC
2013	73	533	606	12.05%
2014	104	795	899	11.57%
2015	96	760	856	11.21%
2016	85	885	970	8.86%
2017	68	742	810	8.40%
2018	69	670	729	8.09%
2019	66	737	803	8.22%
2020	41	708	749	5.47%
2021	52	678	730	7.12%
2022	43	615	658	6.53%

EOGC: Early-onset gastric cancer; LOGC: Late-onset gastric cancer; GC: Gastric cancer.