A case of drug-induced interstitial pneumonia due to pemetrexed

Abstract

Background. Pemetrexed is a multitarget antifolate agent approved for the treatment of patients with malignant pleural mesothelioma and advanced non-small cell lung cancer. The role of pemetrexed, especially in the treatment of lung cancer, continues to expand. Adverse drug reactions are mild, but there have been some reports of pemetrexed inducing interstitial pneumonitis. Case. A 76-year-old woman was admitted to our hospital because of exertional dyspnea. A chest X-ray film revealed a large right pleural effusion. Based on a systemic examination, she was given a diagnosis of non-small cell lung cancer (adenocarcinoma, T3N0M1a). She was given pemetrexed as 1st line chemotherapy. Ten days after the 3rd cycle, she suffered from exertional dyspnea and a dry cough. Chest high-resolution computed tomography findings showed diffuse, ground-glass opacities and interlobular septal thickening, mainly in the left lung. Transbronchial lung biopsy revealed alveolitis, and her bronchoalveolar lavage fluid showed marked lymphocytosis. A drug lymphocyte stimulation test was positive for pemetrexed. We began corticosteroid therapy, and her symptoms and radiographic findings improved. The clinical course suggested pemetrexed-induced interstitial pneumonitis. Conclusion. We present a case of drug-induced interstitial pneumonitis associated with pemetrexed in a patient with advanced non-small cell lung cancer. Because pemetrexed is being prescribed with increasing frequency, especially for non-small cell lung cancer, we believe that clinicians should be aware of this rare but severe pulmonary complication during the management of patients with treatment regimens including pemetrexed. © 2011 The Japan Lung Cancer Society.