What Is Carney Complex?

Introduction

Carney complex is a rare genetic condition that causes skin abnormalities and noncancerous (benign) tumours to develop in children and young adults. It is most often caused by a gene mutation that is passed down from parents to children. The specific symptoms and clinical features of Carney complex can vary greatly from person to person.¹

This article will tell you everything you need to know about Carney complex, including its characteristic signs and symptoms, how it is diagnosed, and treatment options.

Understanding Carney Complex

Carney complex is a genetic disorder caused by a mutation in the PRKAR1A gene. The mutation can occur spontaneously (for no apparent reason), but it is more commonly passed down by a parent.¹

Whilst Carney complex is present at birth in people possessing a certain genetic mutation, signs and symptoms of the condition do not usually appear until adolescence or early adulthood. Therefore, the common age of diagnosis is 20.¹

Signs and Symptoms of Carney Complex

The signs and symptoms of Carney complex can vary from person to person. The most common clinical features of Carney complex include lentigines (dark spots or lesions on the skin), myxomas (tumours commonly found in/on the heart), and endocrine tumours.

Multiple lentigines

Individuals with Carney complex may notice small black or brown spots on their skin, which are known as lentigines. These spots often resemble freckles but are usually darker and range between 2 and 10 millimetres in diameter. Lentigines can form anywhere but are commonly found near the eyes, lips, ears and genitals. These spots can be present at birth but, in most cases, increase in number during puberty and tend to fade in the 40s. Patients may also develop mole-like blue or black spots on the skin known as blue nevi.¹

Myxomas

Some people with Carney complex are more prone to developing a type of tumour known as myxoma. Myxomas are non-cancerous tumours made of connective tissue. The most common myxomas are found in the heart and are known as cardiac myxomas. Myxomas can develop in any chamber(s) of the heart and can cause serious complications if they obstruct normal blood flow. Serious complications include stroke, blood clots, heart failure, sudden death and an uneven heart rhythm.¹

Less commonly, myxomas can be found in other parts of the body such as the eyes, breasts, genitals, bones and skin. Most people with Carney complex develop benign tumours, but these can sometimes become cancerous.¹

Endocrine tumours

Tumours can also form in the glands that make hormones, which are together known as the endocrine system. The hormones produced by these glands are secreted into the bloodstream and travel to various parts of the body, where they are involved in vital processes, including regulating heart rate, blood pressure and body temperature.¹ Some of the endocrine glands affected by the Carney complex include: 

Adrenal glands

The most common endocrine tumour condition in patients with Carney complex is known as primary pigmented nodular adrenocortical disease (PPNAD), which affects around 25% of patients. PPNAD causes the development of small nodules affecting the adrenal glands, which produce the hormone cortisol that helps the body respond to stress. PPNAD can cause levels of cortisol in the blood to increase, which can result in a disorder known as Cushing’s syndrome. If left untreated, PPNAD can also cause diabetes, hypertension, osteoporosis, and slow growth in children.^1,2

Pituitary gland

Some individuals may develop a benign tumour (adenoma) on the pituitary gland. The pituitary gland is found in the brain and regulates the production of several hormones. Tumours on the pituitary gland can increase its production of growth hormone, ultimately triggering a condition known as acromegaly. Acromegaly is a progressive condition that can result in the abnormal enlargement of the bones of the arms, legs, and head, as well as accelerated growth leading to tall stature.²

Thyroid gland

Up to 75% of people with Carney complex have multiple nodules affecting the thyroid. Symptoms of thyroid adenomas include weight loss, excessive sweating, and fatigue. In most cases, these nodules are benign, non-functioning adenomas. However, in rare cases, thyroid cancer may develop in people with a history of multiple thyroid nodules.¹

Reproductive organs

Males with Carney complex may develop a testicular tumour called a large-cell calcifying Sertoli cell tumour (LCCSCT). These tumours are formed from small deposits of calcium and are almost always benign. However, they can cause early puberty (precocious puberty) or breast development. Depending on their size, these tumours may affect fertility by blocking the small tubes that transport sperm. Around one third of males with Carney complex have these tumours and they are usually present during the first decade of life.²

Although less common, some females with Carney complex may develop ovarian cysts or growths in the milk ducts of the breast (ductal adenomas). In rare cases, ovarian cysts may develop into ovarian cancer.

Diagnosis of Carney Complex

A diagnosis of Carney Complex is made by taking and considering a patient’s medical history, symptoms, clinical evaluation, and a variety of tests. 

Depending on your symptoms, your doctor may recommend the following diagnostic tests:

• Echocardiogram - to detect the presence of cardiac myxomas
• Imaging tests - such as an ultrasound, MRI, CT scan or X-ray
• Blood and urine tests (to check hormone levels)
• Skin biopsy
• Genetic testing

Treatment and Management of Carney Complex

Treatment for Carney complex depends on several factors, including the severity of the patient’s condition as well as their age, symptoms, personal preferences, and overall health. 

The most common treatment options are:

• Open heart surgery - to remove cardiac myxomas
• Surgery to remove tumours in the skin or glands

Prognosis

If you are diagnosed with Carney complex, your doctor may recommend regular tests to check hormone levels and your overall health.¹

These regular tests may include:¹

• Blood tests
• An annual echocardiogram
• Endocrine system evaluation
• An annular testicular ultrasound
• Thyroid ultrasound
• Skin checks

Although it is a lifelong condition, people with Carney complex may still have a normal life expectancy which is why it is very important to keep up with your regular screenings and follow-up appointments.¹

FAQs

Can tumours return after treatment?

Yes, it is common for tumours to return.¹

Is Carney complex cancerous?

In most cases, the tumours that develop in people with Carney complex are benign. However, these tumours can become cancerous over time. It is important to keep up with regular tests and follow-up appointments to identify any changes to tumour(s).¹

How can I prevent Carney complex?

There is no way to prevent Carney complex. However, if you are pregnant, genetic amniocentesis can be used to detect if your baby has the genetic mutations associated with Carney complex.

When should I see a doctor?

If you feel that you have any symptoms of Carney complex, you should immediately see a doctor. Cardiac myxomas can interfere with blood flow and cause blockages which can lead to stroke, heart failure or sudden cardiac arrest. You should contact a healthcare provider immediately if you have:

• Changes in your heartbeat
• Shortness of breath
• Coughing
• Fatigue
• Swelling in the ankles, feet or abdomen

Summary

Carney complex is a genetic disorder that causes skin abnormalities and benign tumours throughout the body, and is more commonly observed in children and young adults. The typical symptoms of Carney complex include freckle-like skin spots that can form anywhere but are more commonly found near the eyes, lips and genitals. As well as this, some people develop tumours in their heart (known as cardiac myxomas) or tumours in the bones, breasts, genitals, skin, or endocrine glands. In most cases, these tumours are benign, but some can become cancerous over time. Your healthcare provider may recommend removing these tumours if they cause problems with your heart or endocrine system and monitoring others. The removal of these tumours will involve open heart surgery (in the case of myxomas) or general surgery to remove tumours in the skin or glands. Although treatment can result in the successful removal of a tumour, tumours can return - so it is important to keep up with regular tests and follow-up appointments to manage your symptoms and help you stay healthy.