Is adrenal cancer common? Many patients and family members of adrenal tumors often ask similar questions. In fact, with the development of science and technology, various human examination techniques are developing continuously, and doctors’ treatment level is also improving under the driving force of science and technology. A significant portion of adrenal tumors are found by patients during physical examination and other circumstances, not intentionally detected, so they are called Incidentaloma of the adrenal gland. Some of these tumors are malignant and are classified as malignant pheochromocytoma and adrenocortical carcinoma depending on the site of development. The incidence of malignant pheochromocytoma ranges from 2 to 8 per million people per year, while the incidence of adrenocortical carcinoma ranges from 0.5 to 2 per million people per year. Among them, adrenocortical carcinoma accounts for 2%-3% of the incidental adrenal tumors.