Definition:

Carney complex (CNC) is a rare multiple neoplasia syndrome characterized by pigmented lesions of the skin and mucosa, cardiac, cutaneous and other myxomas, and multiple endocrine tumors. Further manifestations include primary pigmented nodular adrenocortical disease (PPNAD) [DS:H00260] leading to Cushing's syndrome [DS:H01431], pituitary adenomas [DS:H01102], thyroid nodules, testicular neoplasms, ovarian cysts, psammomatous melanotic schwannomas, ductal breast adenomas and osteochondromyxomas. Most CNC patients initially present with adrenocorticotropic hormone (ACTH)-independent Cushing's syndrome due to PPNAD or heart myxomas. Skin lesions are the most common CNC manifestation: lentigines are present in 70 to 75% of patients with CNC. Blue nevi are also typical of CNC. CNC is caused by inactivating mutations or large deletions of the PRKAR1A gene coding for the regulatory subunit type I alpha of protein kinase A (PKA). It may be inherited as an autosomal dominant trait but in a significant number of patients the disease is sporadic, presumably due to de novo mutations.