Successful treatment of non-small-cell lung cancer with afatinib and a glucocorticoid following gefitinib- and erlotinib-induced interstitial lung disease: A case report.

Epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI)-induced interstitial lung disease (ILD) may be a life-threatening condition that may develop during treatment of lung cancer patients harboring EGFR mutations. We herein present the case of a 41-year-old female patient diagnosed with lung adenocarcinoma with an EGFR mutation (exon 19 deletion). The patient was treated with gefitinib followed by erlotinib and developed ILD induced by both EGFR-TKIs; furthermore, the patient acquired resistance to EGFR-TKI treatment. A repeat biopsy revealed a T790M mutation, which is associated with resistance to first-generation EGFR-TKIs, along with an exon 19 deletion identified by cytology of the pleural fluid. Treatment with afatinib and prednisolone resulted in tumor shrinkage, without worsening of the ILD. The present case demonstrated that combination treatment with afatinib and a glucocorticoid may be effective for the treatment of lung cancer patients who develop EGFR-TKI-induced ILD.