Tuberous sclerosis complex (TSC) is a genetic predisposition to growths in different parts of the body, and is caused by pathogenic (or harmful) variants in the TSC1 or TSC2 genes. Most often these growths are benign (non-cancerous) and occur on the skin, kidneys, heart, lung, and brain. Both men and women can be diagnosed with TSC. While signs of the condition can usually appear in childhood, some individuals do not know they have TSC until they are adults because they have mild symptoms, or because TSC is relatively uncommon.
Individuals with TSC can live normal lifespans, but they may develop serious health problems if they are not closely monitored by a healthcare provider experienced with the condition. TSC can potentially affect multiple body systems, however it affects individuals differently, even those within the same family.
Pathogenic variants in the TSC1 and TSC2 genes are inherited in an autosomal dominant pattern, meaning that children of someone who carries a pathogenic variant each have a 50% risk to inherit the variant and associated cancer risks. In one third (33%) of cases of TSC, someone has inherited a pathogenic variant in the TSC1 or TSC2 gene from a parent. In the other two thirds (66%) of cases, the variant was not inherited from a parent, and is something that is new to that person in the family (called de novo). Notably, women and men both have the TSC1 and TSC2 genes and have the same chances to inherit and pass down variants in these genes. Therefore, both sides of the family are important when assessing inherited risk.
There can be many different findings throughout many parts of the body in someone who has TSC. Here are some things that a doctor may look for to diagnose someone with TSC:
Genetic testing for pathogenic variants in TSC1 and TSC2 are currently available, but there are a few different ways to approach testing:
Determining whether an individual meets criteria for genetic testing for TSC is very complex, and would likely be best left to a genetic counselor or other healthcare provider. TSC can be diagnosed by a clinical exam performed by a physician familiar with TSC, or by genetic testing for pathogenic variants in the TSC1 and TSC2 genes. About 95% of people who have a clinical diagnosis will be found to have a pathogenic variant in either the TSC1 or TSC2 genes. The remaining 5% may have a change in another gene that causes TSC that we have not yet discovered.
Medical management for someone with TSC can be complex, and should be overseen by a medical provider who is familiar with TSC. Because TSC affects people in very different ways, medical management should be tailored to an individual’s specific needs. Some options for treatment include:
This is not a comprehensive list of recommendations, as many of these are tailored to meet someone’s specific needs and current health concerns.
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