Among these studies, a microarray analysis (4) showed that 91 genes are differentially expressed between adrenocortical carcinomas (ACCs) and adrenocortical adenomas (ACAs) of adult patients, including the TCF21 gene, which was two times lower in ACCs than in ACAs or in normal adrenal cortex samples. The gene discussed is TCF21; the disease is adrenal cortex carcinoma.