Activating somatic mutations in the CTNNB1 gene have been reported at a similar prevalence in both APAs (27% of 26 tumors, with a higher proportion in nonfunctioning adenomas compared with cortisol-producing adenomas) and malignant adrenocortical tumors (31% of 13 adrenocortical carcinomas) [63]. This evidence concerns the gene CTNNB1 and adenoma.