In one study, Knott et al. reported significantly elevated levels of serum FGF-21 in a cohort of breast cancer patients [increased levels noted in 37/45 (82,2%) patients relative to those of a group of healthy control subjects (n=51); the respective median serum FGF-21 concentrations of the two groups were 224.56 and 76.86 pg/mL (p<0.0001)] (37). Here, FGF21 is linked to breast carcinoma.