Clinicopathological and molecular study of penile melanoma

Abstract

Aims: To examine the clinicopathological features of a series of penile melanomas and screen for mutations in the BRAF and KIT genes, which are seen in melanomas from other sites.

Methods and results: 12 patients with penile melanoma were identified over a 10-year period in two supra-regional networks in the UK. The 2- and 5-year survival was 61% and 20%, respectively. Half the patients had lymph node involvement at presentation; this was a poor prognostic indicator. KIT exons 11, 13, 17 and 18, and BRAF codons 600 and 601 were analysed for mutations by Sanger sequencing and pyrosequencing, respectively. None of the tumours showed either KIT mutations or the BRAF V600E mutation.

Conclusion: Penile melanomas are extremely rare and have a similar prognosis to melanomas elsewhere, but they often present late, leading to a poor outcome. The mutations seen in melanomas from other sites appear to be rarely present in these tumours.