Absence of BRAF and HRAS mutations in eruptive Spitz naevi.

ABSTRACT

BACKGROUND: Eruptive Spitz naevi have been reported rarely in the literature. In solitary Spitz naevi, BRAF and HRAS mutations, as well as increased copy numbers of chromosome 11p have been identified. OBJECTIVES: To investigate the genetic changes underlying eruptive Spitz naevi. METHODS: We report on a 16-year-old boy who developed multiple disseminated eruptive Spitz naevi within a few months. We analysed BRAF, HRAS, KRAS and NRAS genes in 39 naevi from this patient for hotspot mutations. Furthermore, comparative genomic hybridization analysis was performed in three lesions. RESULTS: None of the Spitz naevi displayed a mutation in the analysed genes, and no chromosomal imbalances were observed. Conclusions Our results indicate that the typical genetic alterations described in solitary Spitz naevi appear to be absent in eruptive Spitz naevi. Yet unknown alternative genetic alterations must account for this rare syndrome.