Acute interstitial lung disease in a patient with anaplastic lymphoma kinase-positive non-small-cell lung cancer after crizotinib therapy.

Crizotinib, an orally active multi-targeted small-molecule anaplastic lymphoma kinase (ALK) inhibitor, is an effective treatment modality for advanced ALK-positive non-small-cell lung cancer (NSCLC). Most drug-related adverse events are mild to moderate; however, some patients may develop acute interstitial lung disease (ILD) which is sometimes fatal. We present a case of crizotinib-associated ILD in a 47-year-old woman treated with crizotinib for metastatic adenocarcinoma of the lung. The patient presented with acute breathlessness and hypoxaemia in the second month of crizotinib therapy; radiological and histopathological work-up was suggestive of acute interstitial pneumonia. The patient improved clinically with corticosteroid therapy and was successfully re-challenged with crizotinib. In conclusion, while treating NSCLC patients with crizotinib, it is important to promptly investigate and treat any new-onset respiratory symptoms, as the latter could represent an adverse effect related to therapy. Prompt discontinuation of the offending drug and initiation of corticosteroid therapy may prevent adverse outcomes.