[Transient liver injury caused by gefitinib]

Gefitinib blocks epidermal growth factor receptor autophosphorylation and subsequently the signal transduction pathways implicated in proliferation, metastasis, invasion, and angiogenesis. Reported adverse reactions to gefitinib include liver injury that is not fully understood. Liver injury was observed in 5 (12.2%) of 41 patients with non-small cell lung cancer who received gefinitib monotherapy. Onset of liver injury was seen between 28 and 56 days after initiation of administration. Two patients had Grade 2 liver injury and 3 patients, Grade 3. In 4 patients, liver injury was temporary, lasting during a period of continuous gefitinib administration. In another patient, gefitinib was discontinued because of the onset of liver injury, which improved when gefitinib administration was restarted. Gefitinib is necessary in most patients whose lung cancer is refractory to cytotoxic chemotherapy, because no other treatment regimens are available at present. The rate of liver injury in cases treated with gefitinib is high, and so it is necessary to observe liver function carefully, but the liver injury due to this drug is often transient. However, the use of gefitinib in many cases appears to be a necessity.