Previous studies have demonstrated the association between ABO blood group antigens and clinical outcome in several human cancers, such as esophageal squamous cell cancer (Shiratori et al., 2017), laryngeal cancer (Jin et al., 2016), gastric cancer (Xu et al., 2016) (Angelov et al., 2014) and non-small cell lung cancer (Li et al., 2015). Here, ABO is linked to gastric cancer.