The expression levels of key metabolites in the two groups were represented by box plots (Figure 3E), the levels of aminoadipic acid (FC = 1.39, p < 0.05) and Human Fibrinopeptide B residual (FC = 1.25, p < 0.05) increased obviously, while L-Histidine (FC = 0.35, p < 0.01) decreased in patients with invasive BC comparing with BE. The gene discussed is FGB; the disease is breast cancer.