Analysis of prognostic factors and outcomes of gastric cancer in younger patients: A case control study using propensity score methods

Table 1 Clinicopathological features of the patients

Clinicopathological feature	Younger patients (n = 112)	Older patients (n = 112)	P-value
Gender			0.007
Male	49	70
Female	63	42
BMI (mean ± SD, kg/m2)	22.4 ± 3.4	23.1 ± 2.7	0.086
Comorbidity			< 0.001
No	100	74
Yes	12	38
Size of main lesion (mean ± SD, mm)	4.1 ± 3.1	3.9 ± 3.3	0.604
Histologic type			< 0.001
Well differentiated	7	29
Moderate differentiated	19	34
Poorly differentiated	70	41
Signet ring cell	14	5
Other	2	3
Lauren classification			< 0.001
Intestinal	18	58
Diffuse	72	34
Mixed	22	20
Tumor location			0.154
Upper	15	15
Middle	40	25
Lower	55	70
Whole	2	2
T stage1			0.045
EGC	50	66
AGC	62	46
N stage1			0.132
N0	67	72
N1	12	16
N2	11	14
N3	22	10
Stage1			0.036
I	57	75
II	21	11
III	34	26

¹Based on the 7^th edition of the American Joint Committee on Cancer classification.

Table 2 Postoperative outcomes

Postoperative outcomes	Younger patients (n = 112)	Older patients (n = 112)	P-value
Operative time (min, mean ± SD)	207.3 ± 57.1	205.7 ± 56.7	0.832
Hospital stay (d, mean ± SD)	7.9 ± 2.6	10.1 ± 13.0	0.087
Operative method			0.268
Laparoscopy	46	37
Open	66	75
Type of gastrectomy			1.000
Total	28	28
Subtotal	84	84
Type of anastomosis			0.856
B-I	48	52
B-II	35	32
R-Y	29	28
Lymph node dissection			< 0.001
D2	43	79
Over D2	69	33
Number of retrieved lymph nodes (mean ± SD)	41.4 ± 16.4	36.3 ± 13.2	0.010
Cancer-related combined resection			0.409
No	107	103
Yes (number of patients)	5	9
Spleen1	4	6
Pancreas1	0	3
Liver1	0	1
Adrenal gland1	0	1
Small bowel1	1	0
Ovary1	1	0
Median follow-up duration (mo, range)	79.2 (8.0-137.7)	80.3 (0.7-137.5)	0.523
Postoperative complications			0.297
No	102	96
Yes	10	16
Wound problem	3	5
Intra-abdominal bleeding	1	1
Intra-luminal bleeding	3 (12)	4 (12)
Ileus	1	1
Duodenal stump leakage	0	22
Acute pancreatitis	0	1
Pulmonary disease	0	2
Hepatic disease	1	0
Dumping syndrome	1	0

¹The number of resected organs is a combined number;

²Intra-luminal bleeding was treated endoscopically; duodenal stump leakage required re-operation.

Table 3 Tumor recurrence and patterns

Postoperative outcomes	Younger patients (n = 112)	Older patients (n = 112)	P-value
Median follow-up duration (mo, range)	79.2 (8.0-137.7)	80.3 (0.7-137.5)	0.523
Chemotherapy (stage II or higher) n (%)	49/55 (89.1)	36/37 (97.3)	0.235
Tumor recurrence			0.169
No	93	101
Yes	19	11
Time to recurrence after surgery (mo, mean ± SD)	17.8 ± 9.8	18.5 ± 12.6	0.862
Recurrence patterns1
Locoregional	6	5
Hematogenous	6	5
Peritoneal	10	3
Distant lymph nodes	2	2

¹Combined numbers.