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

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.