Does basal cell carcinoma belong to the spectrum of sorafenib-induced epithelial skin cancers?

The multikinase inhibitor sorafenib is therapeutically used in various malignancies. Multiple cutaneous side effects are well described but recent reports indicated a possible association of epithelial skin cancer growth during sorafenib therapy. To our knowledge, few cases of actinic keratoses and variants of squamous cell carcinomas associated with sorafenib have been published. We report 2 patients who developed a basal cell carcinoma (BCC) while treated with sorafenib. Interestingly BCC is a tumor which has not been described yet in association with sorafenib therapy. The tumors were excised completely. After termination of sorafenib treatment, no new BCCs or other epithelial skin cancers occurred. There is accumulating evidence in the literature that sorafenib and possibly other targeted agents are associated with an increased occurrence of epithelial skin cancers. These observations are summarized here and complemented by the new observation that also BCCs might be associated with sorafenib therapy. The pathogenetic mechanisms are unclear so far but induction of the mitogen-activated protein kinase pathway in wild-type RAF cells by RAF inhibitors might play a role. Patients should be informed of this possible side effect and undergo regular dermatological controls before and during sorafenib therapy.