Carney complex is a hereditary condition characterized by the risk of the individual developing various types of masses. The tumour can be benign meaning it’s not cancerous or malignant which can grow and invade other parts of the body. The affected individual may also exhibit pigmentation of the skin and the symptoms may develop in their early 20s. Although these affected individuals are at the risk of developing cancer, most of the tumours they develop are noncancerous. Carney complex is a rare condition that is reported to have affected less than 750 cases.
Causes
This condition is inherited in an autosomal dominant pattern meaning one copy of the defective gene can cause this disorder. Although 80% of the cases are inherited from one of the affected parent, the rest of the cases are caused by a new genetic mutation with no history of its prevalence in the family. The gene identified to cause this condition is PRKAR1A that provide information for producing a part of an enzyme known as protein kinase A which is essential for the cellular growth and division. The production of a part of type 1 alpha by the gene PRKAR1A regulates the turning on and off of the enzyme protein kinase A. Abnormality in type 1 alpha regulation of the enzyme causes the uncontrolled proliferation of the cellular growth that is characteristic of this disorder. Individuals without the mutation in the PRKAR1A appear to exhibit milder symptoms of this disorder.
Symptoms
Most of the cases exhibit the abnormal pigmentation of the skin with brown spots that may develop around the lips, eyes or genitalia and present a blue-black mole known as the blue nevus. The affected individuals are at a higher risk of developing cardiac myxoma which is the benign tumours of the heart and other parts of the body. The heart myxoma is a life-threatening condition causing sudden death as the result of blood flow blockage to the heart. When the tumour develops in the hormone-producing glands they may produce excess amounts of related hormones. Elevated levels of cortisol hormone produced by the pituitary gland can result in cushing syndrome which can cause slow growth in children, fatigue, weight gain and various other symptoms related to this syndrome. When the tumour develops in the pituitary gland it can create an excess amount of growth hormone that can result in a condition known acromegaly that features symptoms such as large hands and feet, arthritis and other related symptoms. The tumour can also develop in other endocrine tissue such as the testes, thyroid and ovaries.
Diagnosis
The diagnosis is determined by the individual’s history, clinical evaluation and in the identification of the signs and symptoms that are characteristics of this condition. The diagnosis is based on the individual featuring at least 2 of the 12 major clinical features of carney complex. The genetic testing of the mutation in the gene PRKAR1A can confirm the condition particularly went the affected individual presents one of the tumours associated with this disorder.
Treatment
The treatment is usually based on the symptoms that are evident in the different cases of this disorder. It is generally advised that these individuals should receive regular screening to identify the potential abnormalities that can develop. In the case of cardiac, cutaneous and mammary myxomas, surgical intervention may be required. The surgical removal of the pituitary tumour may lower the level of growth hormones and those requiring the removal of the thyroid may need hormone supplementation that needs to be taken lifelong. Other forms of treatment consist of providing symptomatic relief and supportive care.
References
https://rarediseases.org/rare-diseases/carney-complex/
http://www.cancer.net/cancer-types/carney-complex
https://ghr.nlm.nih.gov/condition/carney-complex#genes
