Afatinib-induced Interstitial Lung Disease Successfully Treated with Corticosteroids: Case Report and Review of the Literature.

The first-line treatment for advanced epidermal growth factor receptor (EGFR) mutation positive non-small cell lung cancer (NSCLC) includes the use of afatinib and other EGFR tyrosine kinase inhibitors (EGFR-TKIs). While generally well tolerated, a small subset of patients will develop drug-induced interstitial lung disease (ILD) which could lead to drug discontinuation or even death. A 58-year-old female with stage IV NSCLC treated with afatinib presented with dyspnea and rapidly progressive hypoxemia. Imaging of the lungs demonstrated ground glass opacities. Infectious workup was unrevealing, and since drug-induced ILD was suspected early on presentation, high dose corticosteroids were initiated leading to clinical improvement. While the incidence of afatinib-induced ILD is rare, the consequences may be serious and potentially fatal. The presentation is often non-specific and may mimic other common respiratory pathologies making the diagnosis challenging. If therapeutic measures such as corticosteroids are initiated promptly, they can be life-saving.