To explore the detective value of serum micro RNA34a (miR-34a) combined with carcinoembryonic antigen (CEA) and carbohydrate antigen 72-4 (CA72-4) in predicting early recurrence and metastasis of gastric cancer after radical gastrectomy.

A total of one hundred and twenty-six patients with gastric cancer who underwent radical gastrectomy in the First Affiliated Hospital of Harbin Medical University from June 2014 to August 2015 were selected and divided into recurrence and metastasis group (58 cases, metastatic group) and non-recurrence and metastasis group (68 cases, non-metastatic group). The expression levels of serum miR-34a were detected by real-time fluorescent quantitative PCR, serum CEA and CA72-4 levels were detected by electro-chemiluminescence immunoassay. Univariate analysis of the association was carried out between the levels of miR-34a, CEA and CA72-4 and the clinic pathological characteristics of patients, while Cox regression analysis was carried out of the independent risk factors affecting early recurrence and metastasis of gastric cancer after radical gastrectomy. The predictive value of early recurrence and metastasis of gastric cancer after radical gastrectomy was analyzed by ROC curve.

Compared to non-metastatic group, the expression level of serum miR-34a in metastatic group after radical gastrectomy was significantly lower (t=6.142,P<0.001), and serum CEA and CA72-4 levels were significantly higher (t=17.985, 21.415, bothP<0.001). SerummiR-34a (P=0.013), CEA (P=0.013), CA72-4 (P=0.011), and lymph node metastasis (P=0.048) were independent risk factors for recurrence and metastasis of gastric cancer after radical gastrectomy. Individual detection of three indicators showed that the sensitivity of CA72-4 was the highest (94.8%) and that ofmiR-34a was the lowest (70.7%); the specificity of miR-34a was the highest (94.1%) and that of CA72-4 was the lowest (73.5%). The AUC of serum miR-34a, CEA, and CA72-4 combined detection in predicting early recurrence and metastasis after radical gastrectomy was 0.954 (95%CI: 0.923-0.985), the sensitivity was 87.9%, and the specificity was 89.7%.

The expression of serum miR-34a in patients with early recurrence and metastasis of gastric cancer after radical gastrectomy is down-regulated, while the levels of serum CEA and CA72-4 are increased, and combined detection of the three indicators can provide important reference for screening early recurrence and metastasis of gastric cancer after radical gastrectomy.