Adrenocortical carcinoma is a type of cancer that develops in the adrenal glands' cortex, or outer layer. One adrenal gland is found on top of each kidney, making two total. Cortisol, testosterone, aldosterone, and estrogen are among the hormones that the adrenal cortex produces. These hormones regulate both male and female characteristics as well as bodily processes including blood pressure and stress reactivity. A malignant adrenal tumor called an adrenocortical carcinoma (ACC) develops in the adrenal cortex.