Xeroderma Pigmentosum (XP) is a rare inherited skin disorder characterized by hypersensitivity to the sun and ultraviolet (UV) rays. Individuals with XP are highly susceptible to DNA damage caused by UV light phototoxicity due to either lack of the normal cellular repair mechanism or defective repair pathways to manage the damage. XP is a devastating disease for which there is no known cure and that significantly impacts both quality of life and life expectancy. Below are key points regarding XP*:
- Currently there are no FDA approved drugs for the treatment of XP.
- Standard treatment includes high levels of skin protection, including clothing and sun block, and individuals should avoid all UV / sun exposure whenever possible. This still does not prevent UV DNA damage lesions.
- Many children with XP develop their first case of skin cancer by the age of 10, some as early as four years of age.
- For XP patients younger than 20 years of age, the prevalence of skin cancer is almost 5,000 times greater than what would be expected in the general population. Removal of these skin cancers often leads to severe disfigurement.
- Nonmelanoma skin cancer risks may be increased by 150 percent when there is XP confirmed as a diagnosis.
- The risk of other cancers such as ocular and brain cancers also occurs.
- XP patients die young. The average lifespan for someone with XP is 29 – 37 years.
* Sources: https://www.aad.org/public/diseases/a-z/xeroderma-pigmentosum-sensitivity-to-sunlight ; https://medlineplus.gov/genetics/condition/xeroderma-pigmentosum/# ; https://rarediseases.org/rare-diseases/xeroderma-pigmentosum/ ; https://emedicine.medscape.com/article/1119902-overview ; https://link.springer.com/chapter/10.1007/978-981-10-6722-8_14