Prognostic value of ABO blood group in patients with gastric cancer

Previous studies have shown a link between the ABO blood groups and prognoses for several types of malignancies. However, little is known about the relationship between the ABO blood groups and prognosis in patients with gastric cancer (GC). The aim of this study was to investigate the prognostic performance of ABO blood groups in patients with GC.

A total of 1412 GC patients who had undergone curative intent surgery between January 2005 and January 2010 participated in the present study. A prognostic nomogram was constructed to improve the predictive capacity for patients with gastrectomy using R software, and its predictive accuracy was determined by the concordance index (c-index).

The median follow-up period of the 1412 GC patients was 44 mo with 809 alive. Non-AB blood groups were associated with significantly decreased overall survival in GC patients (hazard ratio = 2.59; 95% confidence interval = 1.74-3.86, P < 0.001), but patients in the group AB had a better prognosis than those in the non-AB blood groups. Meanwhile, group A had the worst prognosis among all the blood groups (hazard ratio = 3.14; 95% confidence interval = 2.09-4.72; P < 0.001). In addition, our constructed nomogram, superior to that of the traditional AJCC stage system (c-index: 0.69), could more accurately predict overall survival (c-index: 0.78) in GC patients who had undergone gastrectomy.

The blood group AB is a favorable prognostic factor for GC patients, but the blood group A is an adverse prognostic factor for patients with gastrectomy. Further prospective studies are warranted to confirm this relationship.