Pemetrexed-induced Interstitial Lung Disease Mimicking Hypersensitivity Pneumonia: A Pathologically Proven Case

Intern Med. 2019 Sep 15;58(18):2679-2682. doi: 10.2169/internalmedicine.2548-18. Epub 2019 Jun 7.


We herein report a 45-year-old woman with lung adenocarcinoma stage IV (cT4N3M1a). She was treated with pemetrexed (PEM) monotherapy following four cycles of first-line treatment with carboplatin, paclitaxel, and veliparib. After three cycles of PEM treatment, she presented with dyspnea, and chest computed tomography showed diffuse ground-glass attenuation (GGA), suggesting hypersensitivity pneumonia (HP). Bronchoalveolar lavage revealed a marked increase in lymphocytes (90.5%), and a transbronchial lung biopsy confirmed lymphocytic alveolitis with granuloma. Because her symptoms and diffuse GGA were spontaneously resolved with PEM discontinuation alone, PEM-induced interstitial lung disease was diagnosed. Chest physicians should be aware that PEM can induce HP-type interstitial lung disease.

Keywords: hypersensitivity pneumonia; methotrexate; pemetrexed.

Publication types

  • Case Reports

MeSH terms

  • Adenocarcinoma of Lung / drug therapy*
  • Alveolitis, Extrinsic Allergic / diagnosis*
  • Antineoplastic Agents / adverse effects*
  • Biopsy
  • Diagnosis, Differential
  • Dyspnea / etiology
  • Female
  • Humans
  • Lung Diseases, Interstitial / chemically induced*
  • Lung Diseases, Interstitial / complications
  • Lung Diseases, Interstitial / diagnosis
  • Lung Diseases, Interstitial / pathology
  • Lung Neoplasms / drug therapy*
  • Middle Aged
  • Pemetrexed / adverse effects*
  • Tomography, X-Ray Computed


  • Antineoplastic Agents
  • Pemetrexed