Carney complex

Carney complex (CNC), also known as Carney syndrome, LAMB syndrome (lentigines, atrial myxoma, blue nevi), or NAME syndrome (nevi, atrial myxoma, myxoid neurofibroma, ephelides), is a rare autosomal dominant multiple neoplasia syndrome characterized by spotty skin pigmentation, cardiac and extracardiac myxomas, endocrine overactivity, and schwannomas. The condition affects multiple body systems including the skin, heart, endocrine glands, and nervous system. Characteristic skin findings include lentigines and blue nevi, which often appear on the face, lips, conjunctiva, and genital mucosa. Cardiac myxomas can occur in any chamber of the heart and may lead to serious complications including stroke, heart failure, and sudden death. Endocrine manifestations include primary pigmented nodular adrenocortical disease (PPNAD) causing Cushing syndrome, growth hormone-producing pituitary adenomas leading to acromegaly, thyroid tumors, and testicular tumors including large-cell calcifying Sertoli cell tumors and Leydig cell tumors. Breast myxomas and psammomatous melanotic schwannomas are also characteristic features. The most common genetic cause of Carney complex is a loss-of-function mutation in the PRKAR1A gene on chromosome 17q24.2, which encodes the type 1A regulatory subunit of protein kinase A. This gene is identified in approximately 70% of affected individuals. A second locus has been mapped to chromosome 2p16, though the specific gene has not yet been identified. About 30% of cases arise as de novo mutations without a family history. The disease typically manifests in childhood or young adulthood, with skin pigmentation often being the earliest sign, appearing in the first decade of life. Management of Carney complex requires lifelong multidisciplinary surveillance. Regular echocardiography is essential for early detection of cardiac myxomas, which may require surgical excision to prevent embolic events. Endocrine screening includes evaluation for Cushing syndrome, acromegaly, and thyroid abnormalities. Bilateral adrenalectomy may be necessary for PPNAD-related Cushing syndrome. Genetic counseling is recommended for affected individuals and their families. There is no cure for the condition, and treatment is directed at managing individual manifestations as they arise. Early diagnosis through genetic testing of at-risk family members allows for timely surveillance and intervention.

Common questions about Carney complex