Cushing's Syndrome—Unilateral Adrenal Adenoma

The most frequent form of ACTH-independent Cushing’s syndrome is caused by unilateral adrenocortical adenomas. This condition is diagnosed in patients with a clinical phenotype of Cushing’s syndrome, in the presence of hormonal alterations indicative of hypercortisolism, low plasma morning ACTH levels, and an adrenocortical tumor with radiological characteristics of adenoma. Recent advances in the molecular pathogenesis have revealed that somatic mutations of the gene encoding the catalytic subunit of protein kinase A are the causative event in more than half of the cases. Laparoscopic adrenalectomy is curative in virtually all cases of Cushing’s syndrome due to unilateral adrenocortical adenomas.