Hereditary Paraganglioma-Phaeochromocytoma Syndrome

Common tumours/cancers associated with PGL/PCC syndrome

• Brain tumours
• Gastric tumours
• Kidney cancer
• Head and neck paragangliomas
• Phaeochromocytomas
  

Signs of PGL and/or PCC

Depending on where these tumours develop in the body, they may cause different symptoms (see figure below). The symptoms vary among individuals while some may even be asymptomatic.

Head and neck PGL
Most head and neck PGL tend not to overproduce hormones, and thus individuals do not show the signs associated with abnormal hormonal regulation.

PCC
PCC, which are tumours in the adrenal gland, can release excess hormones that can lead to symptoms such as high blood pressure, a fast heartbeat and excessive sweating.

If these tumours are unundetected or untreated, more serious risks such as heart attacks, stroke or sudden death may occur.

Other symptoms associated with PGLs/PCCs include:

• Excessive sweating
• New onset diabetes
• Weight loss
• Pale appearance
• High blood pressure
  

What other tumours and cancers can be associated with hereditary PGL/PCC syndrome?

There may be an increased risk of kidney or thyroid cancer, and stomach or pituitary tumours developing in individuals with PGL/PCC syndrome. However, these risks are small.

1. Kidney cancer
Individuals with PGL/PCC syndrome may have an increased risk of developing a certain type of kidney cancer.

2. Thyroid cancer
Some individuals with PGL/PCC syndrome may have an increased risk of developing thyroid cancer.

3. Gastric tumours
Individuals with PGL/PCC syndrome may also be at increased risk of developing a type of stomach tumour called gastrointestinal stromal tumours (GISTs). GISTs develop within the walls of the stomach or small intestine.

Small GISTs may not cause any symptoms and are usually detected through bleeding in the gastrointestinal tract.

Some symptoms that an individual with GISTs might experience include:

• Vomiting blood which looks like coffee grounds
• Stools which are black or bloody
• Abdominal pain
• Loss of appetite and weight loss
• Feeling tired and weak
  

4. Pituitary tumours
The pituitary gland is a pea-sized gland found at the base of the brain and produces hormones which regulate growth and sexual function, and controls other glands such as the thyroid and adrenal glands.

Pituitary tumours are almost always benign but can cause problems, as a tumour can result in the pituitary gland making too little or too much hormones. Occasionally, pituitary tumours can cause headaches, or press on the eye nerves causing loss of vision.

What are the tumour and cancer risks associated with hereditary PGL/PCC syndrome?

The risk of tumours/cancers depends on which SDHx gene is faulty.

Note: The conditions associated with different faulty SDHx genes and their risk estimates may change as more information is available. Insufficient information is known about the risk of SDHAF2 carriers, thus it is not included in the table.

While individuals carrying a faulty SDHx gene face an increased risk of the tumours/cancers listed above, it does not mean that they will definitely develop them.