Table 1 presents data showing that patients with recurrent breast cancer had significantly higher levels of serum CDH5 compared with patients that remained recurrence-free for 5 years (P=0.028, Figure 2A) and whilst HPA binding was comparable between the 2 sample groups (Figure 2B) the CDH5:HPA ratio was also significantly elevated (P=0.007) in patients with REC compared with patients with NSR (Figure 2C). This evidence concerns the gene CDH5 and breast cancer.