Prospective study of cutaneous side-effects associated with the BRAF inhibitor vemurafenib: a study of 42 patients

Background: BRAF inhibitors are being developed for the treatment of metastatic melanoma harboring a V600E mutation. The use of vemurafenib significantly increases progression-free survival (PFS) and overall survival (OS) in this population of patients, but is associated with numerous adverse skin reactions. Patients and methods: We carried out a systematic dermatologic study of 42 patients treated with vemurafenib. We collected detailed dermatologic symptoms, photos and biopsy specimens of the skin lesions which enabled us to classify the side-effects. The management and evolution of the skin symptoms are also reported. Results: All patients presented with at least one adverse skin reaction. The most common cutaneous side-effects consisted in verrucous papillomas (79%) and hand foot skin reaction (60%). Other common cutaneous toxic effects were a diffuse hyperkeratotic perifollicular rash (55%), photosensitivity (52%) and alopecia (45%). Epidermoid cysts (33%) and eruptive nevi (10%) were also observed. Keratoacanthomas (KA) and squamous cell carcinoma (SCC) occurred in 14% and 26% of the patients, respectively. Conclusions: These cutaneous side-effects are cause of concern due to their intrinsic potential for malignancy or because of their impact on patients' quality of life. Management of this skin toxicity relies on symptomatic measures and sun photoprotection.