Cumulative risk of skin cancer in patients with Li-Fraumeni syndrome.

Li-Fraumeni syndrome (LFS) is an inherited cancer syndrome, characterized by an early onset of various types of cancers. LFS is associated with a germline mutation in the TP53 gene. The risk of developing skin cancer in patients with LFS is unknown. To evaluate the cumulative risk of skin cancer in patients with LFS and to compare this risk to the general Dutch population. In this retrospective cohort study, all proven TP53 mutation carriers in the Netherlands Cancer Institute were included from their first visit to the Institute until June 2017. Medical charts and pathology reviews cross-referenced with PALGA, the nationwide network and registry of histo- and cytopathology were used to identify incident skin cancers. Cumulative risks were calculated by Kaplan-Meier analysis. Seventy-one patients (59% female) from 33 families were included. Ten patients (14%) developed a total of 19 skin cancers at a median age of 41 (25-65) years. The cumulative risk of skin cancer is 10.4% (95% CI 4.4-23.5%) at age 40, 25.2% (95% CI 12.3-47.6%) at age 60, and a at age 70 this risk is 44.6% (95% CI 22.9-73.9%). The cumulative risks of melanoma and basal cell carcinoma at age 70 are increased compared to the general Dutch population, namely 12.6% (95% CI 3.6-38.4%) and 34.6% (95% CI 15.4-66.2%), respectively. Patients with LFS have an increased risk of developing skin cancer. A dermatological consultation may be considered at least once in individuals with LFS to raise awareness for skin cancer and inform about risk factors.