Recently, we reported that serum levels of the free peptide form of the α-subunit, inhibin pro-αC, were increased in patients with adrenocortical carcinomas and that these levels can be utilized as a tumor marker [21]; inhibin pro-αC levels may be useful for the differentiation between malignant and benign adrenocortical tumors as well as for follow-up of individual patients. This evidence concerns the gene ASAH1 and adrenal cortex carcinoma.