[Prospective study of biotin treatment in patients with erythema due to gefitinib or erlotinib].

Gefitinib anderlotinib, which are epidermal growth factor receptor(EGFR)tyrosine kinase inhibitors(TKIs), have been usedfor the treatment of inoperable andrecurrent non-small cell lung cancer(NSCLC)patients. These drugs are known to cause a skin rash, one of the major side effects, at a high frequency. Biotin is a water-soluble vitamin, andit belongs to the vitamin B family. It is well known that biotin deficiency increases the risk of skin dermatitis. We administered biotin to four patients with skin rash, all of whom were treatedwith either gefitinib or erlotinib andwere unable to be treatedby a steroid ointment alone. In all patients, administration of biotin reduced the skin rash. Surprisingly, in 2 patients in whom EGFR-TKI therapy was discontinued because of the skin rash, the administration of biotin allowed for long-term gefitinib or erlotinib treatment. Biotin may be considereduseful for the treatment of skin rash causedby EGFR-TKIs. Further trials may be needed to confirm the value of biotin in this setting.