The involvement of this alteration in ACT development might appear relatively weak; however, it is noteworthy that overexpression of the epidermal growth factor receptor (EGFR/c-erbB1) is present in 3 to 43% of ACA and 76 to 100% of ACC [29]–[31], and is frequently associated with an overexpression of TGF-α, a natural ligand of EGFR in ACC [30]. This evidence concerns the gene EGFR and adrenal cortex carcinoma.