Cutaneous leukocytoclastic vasculitis due to erlotinib: just an adverse event or also a putative marker of drug efficacy?

Erlotinib is a targeted anticancer therapy with selective inhibitory activity for tyrosine kinase of the epidermal growth factor receptor (EGFR). Different skin reactions have been described linked to these drugs. There are no other reports about erlotinib-induced leukocytoclastic vasculitis (LV) in the erlotinib-bevacizumab regimen for bone metastasis, from a relapsed hepatocellular carcinoma (HCC) in liver-transplanted patients. In our patient a dose reduction and then the suspension of erlotinib was required. After a 2 week withdrawal, the drug was re-challenged at a lower dose. The patient continued it without any skin recurrence, and resulted progression free for 16 months. Thus, we underline the possibility to avoid a permanent withdrawal of erlotinib and to rechallenge with it without any cutaneous toxicity, particularly in patients benefiting from this drug. Moreover, the median overall survival from the initial treatment of bone relapsed patients after liver transplant for HCC is found to be less than 5 months, while our patient died 5 years later. This longer survival encourages further investigations to assess also whether LV, even if rare, might be used as a marker of antitumor efficacy of EGFR inhibitors.