Interstitial Pneumonitis after Treatment with Pemetrexed for Non-small Cell Lung Cancer.

Pemetrexed is approved as a first-line treatment for advanced non-squamous non-small cell lung cancer (NSCLC) with cisplatin and as a single agent for second-line treatment or for patients who show no disease progression after four cycles of platinum-based doublet induction chemotherapy as maintenance therapy. Pemetrexed has a modest toxicity profile and has not traditionally been regarded as a cause of interstitial pneumonitis. Here, we report on a rare case of pemetrexed-induced pneumonitis in a patient with NSCLC.