Autoimmune Pulmonary Alveolar Proteinosis with Suspected Exacerbation after Osimertinib Administration for Lung Cancer

• Published in: Internal medicine (Tokyo, 1992) Vol. 62; no. 8; pp. 1203 - 1206
• Main Authors: Shimoda, Masafumi, Ishii, Haruyuki, Tanaka, Yoshiaki, Morimoto, Kozo, Takemura, Tamiko, Oka, Teruaki, Yoshimori, Kozo, Ohta, Ken
• Format: Journal Article
• Language: English
• Published: Japan Japan Science and Technology Agency 15.04.2023; The Japanese Society of Internal Medicine
• Subjects: Alveoli; Autoantibodies; Autoimmune Diseases - diagnosis; Biopsy; Bronchoscopy; Case Report; Chemotherapy; Colony-stimulating factor; Female; Granulocyte-macrophage colony-stimulating factor; Humans; Internal medicine; Lung - pathology; Lung cancer; Lung Neoplasms - drug therapy; Lung Neoplasms - pathology; Lymphangitis; Middle Aged; Pulmonary Alveolar Proteinosis - chemically induced; Pulmonary Alveolar Proteinosis - diagnostic imaging; lung cancer; anti-granulocyte/macrophage colony-stimulating factor autoantibody; tyrosine kinase inhibitor; pulmonary alveolar proteinosis; osimertinib
• ISSN: 0918-2918; 1349-7235; 1349-7235
• DOI: 10.2169/internalmedicine.0256-22

A 46-year-old woman with lung cancer who received chemotherapy was admitted to our hospital for lower-lobe bilateral ground-glass opacity (GGO). GGO developed after the lung cancer diagnosis, deteriorated after the initiation of osimertinib, and incompletely decreased after interrupting osimertinib; therefore, flexible bronchoscopy was performed. Transbronchial lung biopsy histology and anti-granulocyte/macrophage colony-stimulating factor autoantibody positivity revealed autoimmune pulmonary alveolar proteinosis (aPAP) that did not require treatment. This rare case of aPAP comorbid with lung cancer suggested that using PAP findings to differentiate from drug-induced lung injury or lymphangitis is difficult and that osimertinib was suspected to exacerbate aPAP.