Mutations in SUFU and PTCH1 genes may cause different cutaneous cancer predisposition syndromes: similar, but not the same

Abstract

Many cancer predisposition syndromes are preceded or accompanied by a range of typical skin signs. Gorlin syndrome is a rare multisystem inherited disorder which can predispose to basal cell carcinomas (BCCs), childhood medulloblastomas in addition to various developmental abnormalities; the majority of cases are due to mutations in the PTCH1 gene. Approximately 5% of cases have been attributed to a mutation in the SUFU gene. Certain phenotypic features have been identified as being more prevalent in individuals with a SUFU mutation such as childhood medulloblastoma, infundibulocystic BCCs and trichoepitheliomas. Recently hamartomatous skin lesions have also been noted in families with childhood medulloblastoma, a "Gorlin like" phenotype and a SUFU mutation. Here we describe a family previously diagnosed with Gorlin syndrome with a novel SUFU splice site deleterious genetic variant, who have several dermatological features including palmar sclerotic fibromas which has not been described in relation to a SUFU mutation before. We highlight the features more prominent in individuals with a SUFU mutation. It is important to note that emerging therapies for treatment of BCCs in patients with a PTCH1 mutation may not be effective in those with a SUFU mutation.

Keywords: Basal cell carcinoma; Gorlin syndrome; SUFU; Sclerotic fibroma; Vismodegib.