Association of carcinoembryonic antigen/carbohydrate antigen 19-9 with gastric cancer recurrence and chemotherapy toxicities

Table 1 Baseline patient characteristics, mean ± SD/n (%)

Characteristics	Recurrence group (n = 18)	Non-recurrence group (n = 56)	χ²/t/Z value	P value
Sex
Men	14 (77.8)	41 (73.2)	0.006	0.940
Women	4 (22.2)	15 (26.8)
Age (years)	70.61 ± 10.87	68.82 ± 11.32	0.589	0.558
Tumor differentiation
Poorly differentiated	14 (77.8)	33 (58.9)	2.419	0.298
Moderately differentiated	3 (16.7)	13 (23.2)
Well-differentiated	1 (5.6)	10 (17.9)
TNM stage
Stage II	6 (33.3)	32 (57.1)	3.091	0.079
Stage III	12 (66.7)	24 (42.9)
Lymph node metastasis
Present	4 (33.3)	20 (42.9)	1.132	0.287
Absent	14 (66.7)	36 (57.1)

TNM: Tumor-node-metastasis.

Table 2 Postoperative serum carcinoembryonic antigen and carbohydrate antigen 19-9 levels, mean ± SD

Group	n	First postoperative day		1 month postoperatively		3 months postoperatively		Average value
		CEA (ng/mL)	CA19-9 (U/mL)	CEA (ng/mL)	CA19-9 (U/mL)	CEA (ng/mL)	CA19-9 (U/mL)	CEA (ng/mL)	CA19-9 (U/mL)
Recurrence group	18	62.15 ± 12.84	110.47 ± 31.25	59.33 ± 11.02	105.82 ± 27.19	57.26 ± 12.08	96.45 ± 28.94	59.58 ± 11.95	104.25 ± 28.64
Non-recurrence group	56	46.21 ± 9.14	43.56 ± 13.89	44.87 ± 8.02	41.73 ± 12.05	41.92 ± 8.01	37.15 ± 11.46	44.33 ± 8.39	40.81 ± 12.47
t value		6.842	13.005	6.334	13.415	6.571	12.880	6.017	13.246
P value		< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001

CEA: Carcinoembryonic antigen; CA19-9: Carbohydrate antigen 19-9.

Table 3 Recurrence rates and recurrence-free survival in the elevated and normal carbohydrate antigen 19-9 groups, mean ± SD/n (%)

Group	n	Recurrence rate (%)	Mean RFS
Elevated	20	14 (70.00)	6.25 ± 0.85
Normal	54	4 (7.41)	9.83 ± 0.97
χ²/t value		27.756	14.606
P value		< 0.001	< 0.001

RFS: Recurrence-free survival.

Table 4 Gastrointestinal adverse reaction grades, n (%)

Group	n	Mild	Moderate	Severe
Recurrence group	18	6 (33.33)	8 (44.44)	4 (22.22)
Non-recurrence group	56	33 (58.93)	21 (37.50)	2 (3.57)
Z value		23.970
P value		< 0.001

Table 5 Carcinoembryonic antigen and carbohydrate antigen 19-9 levels across gastrointestinal adverse reaction grades, mean ± SD

Gastrointestinal reaction adverse grades	n	Mean CEA (ng/mL)	Mean CA19-9 (U/mL)
Mild	39	39.87 ± 5.96	38.44 ± 17.27
Moderate	29	54.41 ± 5.27a,1	68.14 ± 26.95a,1
Severe	6	70.34 ± 10.74a,1,2	114.44 ± 42.08a,1,2
F value		8.931	32.216
P value		< 0.001	< 0.001

^aP < 0.05.

¹P vs mild group.

²P vs moderate group.

CEA: Carcinoembryonic antigen; CA19-9: Carbohydrate antigen 19-9.

Table 6 Correlation analysis of carcinoembryonic antigen and carbohydrate antigen 19-9 levels with prognosis

Indicators	CEA		CA19-9
	r value	P value	r value	P value
Recurrence	0.655	< 0.001	0.702	< 0.001
RFS	-0.704	< 0.001	-0.681	< 0.001
Gastrointestinal adverse reaction grade	0.518	< 0.001	0.597	< 0.001

CEA: Carcinoembryonic antigen; CA19-9: Carbohydrate antigen 19-9; RFS: Recurrence-free survival.