Studies performed on plasma samples from breast cancer patients have allowed the identification of specific metabolomic profiles for each cellular subtype: L-tryptophan, LysoPC(14:0), glycoursodeoxycholic acid, lysophosphoethanolamine (LysoPE)(18:2) in luminal A; LysoPE(18:2), LysoPE(18:1(11Z/9Z)), LysoPC(20: 3), biliverdin, LysoPE(16:0) in luminal B; LysoPE(18:1(11Z)/9Z), LysoPC(0:0/16:0), biliverdin, L-tryptophan, LysoPE(18:2) in HER2+; and L-tryptophan, LysoPC(16:0/0:0), LysoPE(18:1(11Z)/9Z) in TNBC (62) Table 2. The gene discussed is ERBB2; the disease is breast cancer.