Carney complex

Carney complex is a disorder that is characterized by changes in skin coloring (pigmentation) and an increased risk of tumors. Many of the signs and symptoms of Carney complex become apparent during adolescence or early adulthood.

Almost all people with Carney complex have areas of unusual skin pigmentation. Brown or black skin spots called lentigines may appear anywhere on the body, but they tend to occur around the lips, eyes, or genitalia. In addition, some affected individuals have at least one blue-black mole called a blue nevus.

People with Carney complex have an increased risk of developing noncancerous (benign) tumors called myxomas in the heart (cardiac myxoma), skin, breast, and other parts of the body. Cardiac myxomas may be found in one or more chambers of the heart. These tumors can block the flow of blood through the heart, which can cause serious complications, including sudden death. Skin myxomas appear as small bumps on the surface of the skin or as lumps underneath the skin. In people with Carney complex, myxomas tend to recur after they are removed.

Individuals with Carney complex may also develop tumors in hormone-producing (endocrine) glands, such as the adrenal glands located on top of each kidney. Approximately 25 percent of people with Carney complex develop a specific type of adrenal tumor called primary pigmented nodular adrenocortical disease (PPNAD). PPNAD causes the adrenal glands to produce too much of the hormone cortisol. High levels of cortisol can lead to the development of Cushing syndrome, which is characterized by weight gain in the face and upper body, slow growth in children, bone loss, fragile skin, fatigue, and other health problems.

Tumors of other endocrine tissues, such as the thyroid, testes, and ovaries, are also seen in people with Carney complex. Many affected individuals have tumors on the thyroid gland called adenomas. Occasionally, people with thyroid adenomas develop thyroid cancer.

In people with Carney complex, adenomas may also form in the pituitary gland, which is located at the base of the brain. A pituitary adenoma usually causes the production of too much growth hormone. Excess growth hormone can lead to a condition called acromegaly, which is characterized by large hands and feet, arthritis, and distinctive facial features that are often described as "coarse."

Approximately 10 percent of people with Carney complex develop a rare tumor called psammomatous melanotic schwannoma (PMS). This tumor occurs in specialized cells called Schwann cells that wrap around and insulate nerve cells. These tumors are usually benign, but they can become cancerous (malignant).

Although most tumors that develop in people with Carney complex are benign, some affected individuals develop cancer over time. Complications associated with cardiac myxomas, PMS, or cancer can shorten the life expectancy for some affected individuals.