Carney complex consists of spotty skin pigmentation in
association with multiple neoplasias (mainly cardiac and endocrine tumors).
The two types of Carney complex are type I and type II. Both types show the
same clinical features.
Myxoma-Spotty Pigmentation-Endocrine Overactivity; Carney
Initially, the term NAME syndrome (acronym for nevi,
atrial myxomas, myxoid neurofibroma, ephelides) was proposed for this condition.
Later, the term LAMB syndrome (acronym for lentigines, atrial myxomas,
mucocutaneous myxomas, blue nevi) was suggested. Both syndromes now are part
of the Carney complex. The American physician J.A. Carney reviewed several
of these cases in 1985 and suggested a common pathogenetic link between the
In the United States, cardiac myxomas occur with a
frequency of 5-10:10,000, of which approximately 7% are associated with
Carney syndrome. The syndrome can present at any age and in either sex. No
sexual predilection has been found.
Autosomal dominant with variable penetrance.
Because type I has been researched more thoroughly, we discuss this type
here. It is caused by mutations of the PRKAR1A gene (protein kinase,
c-AMP-dependent, regulatory, type I, alpha, also called tissue specific
extinguisher 1), which is an important regulator of the serine-threonine
kinase activity catalyzed by the protein kinase A holoenzyme, and has been
mapped to 17q22-q24. The exact function of PRKAR1A in cell cycle regulation,
growth, and/or proliferation in general and Carney complex syndrome in
particular remains to be elucidated, but a function as a tumor suppressor
gene has been discussed.
Cardiac myxomas, while histologically benign, may
cause embolic phenomena, valvular obstruction, and heart failure. Myxomas
are also found in the thyroid and adrenal glands, brain, breasts, and testes.
Nonmyxomatous tumors, such as Sertoli cell tumors of the testis, pituitary
adenomas, and psammomatous melanotic schwannomas, may occur. Primary
pigmented nodular adrenocortical disease, a characteristic micronodular form
of bilateral adrenal hyperplasia, causes a unique, inherited form of Cushing
syndrome. Thyroid and pituitary dysfunction have been observed. Systemic
symptoms may be caused by overproduction of the proinflammatory cytokine
interleukin-6 by myxoma cells.
Based on the clinical findings of pigmented skin lesions
associated with neoplasias (particularly myxomas). The mean age at the time of
diagnosis is 10 to 20 years.
Skin manifestations include dark pigmented skin
lesions (lentigines). Although they can be found anywhere on the body, they
typically are located in the center of the face (i.e., periorally,
perinasally, periorbitally, and in the sclerae). The finding of lentigines
on the lips in association with a myxoma or an endocrine disorder/tumor
should prompt further examinations to rule out Carney complex. Urogenital
(vulvar) lentigines also are considered characteristic for this disorder.
Cardiac myxomas may be solitary or multiple and can occur in any cardiac
chamber, although almost 90% occur in one of the atria. The left atrium
accounts for 80% of ...