Pneumothorax
Multiple bilateral pulmonary cysts are found in >80% of patients and more than half experience one or more episodes of pneumothorax. Unlike other cystic lung diseases such as lymphangioleiomyomatosis and pulmonary Langerhans cell histiocytosis, BHDS does not lead to progressive loss of lung function and chronic respiratory insufficiency.
Cancer risk
There is an increased chance (up to 30%) to develop kidney cancer, which is often bilateral (in both kidneys). Several types of kidney cancer can be seen in a person with BHDS, but the most characteristic is a mix of two types, called “chromophobe” and “oncocytoma.” Sometimes, kidney tumors seen in people with FLCN mutations can be non-cancerous.
Other Medical Concerns
Patients with FLCN mutations often have multiple non-cancerous tumors on their skin. They are also at an increased risk for developing cysts in the lungs and too much air in the chest, which can cause a lung to collapse (pneumothorax).
Family members
Patients’ close relatives (like parents, brothers, sisters, children) have a 50/50 random chance of inheriting the FLCN mutation that have been identified, and other family members (like aunts, uncles, cousins) may also inherit it. All these relatives can be tested for this same FLCN mutation. Depending on the family history, those who do not have it may not have an increased lifetime chance (above the general population) to develop cancer.
FLCN