Interstitial lung disease in patients with non-small-cell lung cancer treated with epidermal growth factor receptor inhibitors

Interstitial lung disease (ILD) refers to a diverse range of pulmonary fibrotic disorders and may be hard to accurately diagnose, as distinguishing it from other pulmonary diseases can be difficult. Estimations of the incidence in populations are confounded by the complexity of the different forms of the disorder. In addition, ILD is a comorbid disease of lung cancer and is seen after most forms of chemotherapy and radiotherapy for advanced lung cancer. Incidences of ≥10% have been reported; however, whatever the true incidence, both chemotherapy and radiotherapy enhance the risk of developing ILD. ILD has also been reported with the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors, including erlotinib (Tarceva, OSI-774) and gefitinib (IRESSA). In a large number of gefitinib-treated patients (n>185,000) an incidence of approx 1% has been observed (approx 2% in Japan; 0.3% in the rest of the world). Nevertheless, as with other treatments for advanced non-small-cell lung cancer, the clinical benefit outweighs the risk of ILD. In this article, we review the data on ILD with EGFR inhibitors and other common lung cancer treatments.