| Phakomatoses | |
|---|---|
| Other names | Neurocutaneous syndromes |
| Specialty | Medicine, Neurology, Neurosurgery, Medical Genetics, Dermatology, Psychology, Psychiatry and more |
| Symptoms | Dermal, ocular and CNS benign and malignant tumors. Various additional potential complications. |
| Complications | Numerous potential complications including cosmetic, intellectual disability, epilepsy, organ failure and more. |
| Usual onset | Childhood (most commonly) |
| Duration | Lifelong |
| Causes | Genetic causes |
| Treatment | Highly variable. Many require lifelong surveillance and various treatments depending on the particular syndrome and presentation. |
Phakomatoses, also known as neurocutaneous syndromes, are a group of multisystemic diseases that most prominently affect structures primarily derived from the ectoderm such as the central nervous system, skin and eyes. The majority of phakomatoses are single-gene disorders that may be inherited in an autosomal dominant, autosomal recessive or X-linked pattern. Presentations may vary dramatically between patients with the same particular syndrome due to mosaicism, variable expressivity, and penetrance.[1]
Many phakomatoses are caused by mutations which alter functioning of the RAS–mitogen-activated protein kinase (MAPK) pathway and the PI3K/AKT/mTOR pathway that regulates cellular growth, differentiation, proliferation and death.[2] This results in a tendency for individuals with these mutations to develop various types of benign or malignant tumors depending on the particular mutation. The presence of these tumors may result in functional and/or cosmetic problems depending on their type and location.