BRAF Inhibitor-Associated Granulomatous Dermatitis: A Report of 3 Cases.

Cutaneous toxicities associated with BRAF inhibitor treatment in patients with metastatic melanoma have been well described. We present a rare association of granulomatous dermatitis in association with the BRAF inhibitor vemurafenib. Three patients with metastatic melanoma all presented with asymptomatic papular eruptions 8-21 months into vemurafenib therapy. Skin biopsies confirmed the diagnosis of granulomatous dermatitis. Other causes of granulomatous dermatitis including infectious agents and sarcoid were excluded. Treatment with potent topical and oral steroids improved the eruptions, but only after the cessation of vemurafenib did all 3 cases of granulomatous dermatitis completely resolve within 2 weeks. It is important to recognize that this association, unlike most other BRAF inhibitor-related skin toxicities, can occur many months after commencement of therapy and that vemurafenib treatment can be continued without clinically significant adverse effects.