Successful treatment of gefitinib-induced acute interstitial pneumonitis with high-dose corticosteroid: a case report and literature review.

Cytotoxic chemotherapy offers a modest benefit for patients with advanced non-small cell lung cancer (NSCLC), with response rates of 20-35% and median survival of 10-12 months. Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), gefitinib and erlotinib are active against lung cancer. In retrospective studies, EGFR-TKI therapy among patients harboring EGFR mutations showed response rates higher than 65% and a median survival of 20-30 months. Gefitinib is well tolerated and less toxic compared to conventional cytotoxic drugs, but gefitinib-related interstitial lung disease (ILD) has been reported as a serious adverse effect. Although the mechanism remains unknown, multivariate analysis revealed male sex, history of smoking, and the coexistence of interstitial pneumonia or pre-existence of pulmonary fibrosis and poor performance status were all significant risk factors. Here, we reported a case of gefitinib pneumonitis with severe hypoxemia and impending respiratory failure who showed poor response to intermediate dose of systemic steroids but good recovery with high-dose pulse therapy.