Nævus éruptifs sous sorafénib

Background: Sorafenib is a new multikinase inhibitor recently approved for renal cell carcinoma and hepatocarcinoma. Among other targets, it blocks the kinase function of the RAF gene products including V600E mutant BRAF, which is frequently found in both melanoma and naevi. Cutaneous side effects are frequent with sorafenib, but no naevus modification has been reported until now. Patients and methods: Five cases of eruptive naevi in patients treated with sorafenib are reported. The mean duration of sorafenib treatment was 9.2 months when naevi eruption was noticed. The patients presented with about 100 to more than 200 small, homogenous, dark-brown naevi located mainly on the trunk and upper limbs. Discussion: Eruptive melanocytic naevi have been reported in association with blistering diseases, and more generally in a setting of immunosuppression. We hypothesize that naevi appearance could be linked to an anti-senescence effect of sorafenib via its action on the MAP kinase pathway. Further prospective studies are needed to explore the relationship between sorafenib and the biology of naevi.