CTICasesPembrolizumab-Associated Organizing Pneumonia (Checkpoint Inhibitor Toxicity)
▶ Watch on YouTube — age-restricted, cannot embed here
Imaging findings
A patient treated for melanoma, without known metastatic lung disease in June. By September, new, extensive consolidated opacities appeared in the right lower lobe. In November, similar well-marginated, non-segmental consolidations were seen in the left lower lobe and right middle lobe. A January scan showed a waxing and waning pattern, with some areas improving and new areas developing, including a possible reverse halo sign. Lung biopsy confirmed exuberant organizing pneumonia with fibroblastic plugs, consistent with acute fibrinous organizing pneumonia.
Key takeaways
This case illustrates pembrolizumab (a checkpoint inhibitor)-associated pulmonary toxicity, presenting as organizing pneumonia. The characteristic imaging pattern includes multifocal, non-segmental consolidated opacities with a waxing and waning course. These immune-mediated adverse events are increasingly recognized with newer biologics like checkpoint inhibitors. Pathological confirmation often reveals organizing pneumonia with fibroblastic plugs. Clinicians should be aware that these drugs can cause various immune-modulated lung toxicities.
AI-assisted summary — may contain errors. Verify against the source video. Learn more
More from this webinar
- Congenital Coronary Anomalies with Origin from All Three Aortic CuspsCongenital
- Intramyocardial Lipoma Detected by Tissue MappingNeoplastic
- Extensive Left Atrial Thrombus Diagnosed with Dual-Energy CTVascular
- Adenocarcinoma of the Lung with Adrenal MetastasisNeoplastic
- Metastatic Meningioma to the LungNeoplastic
- Coexisting Langerhans Cell Histiocytosis and Growing Pulmonary HamartomaNeoplastic
- Acute Onset Langerhans Cell Histiocytosis in an Elderly SmokerNeoplastic
- Chronic Pulmonary Thromboembolism Mimicking SarcomaVascular
See all cases from January 29, 2016 →
Related ILD cases
- Fibrotic Nonspecific Interstitial Pneumonia (NSIP) in Anti-Synthetase Syndrome
- Rapidly Progressive Interstitial Lung Disease in Amyopathic Dermatomyositis
- Lymphangioleiomyomatosis (LAM) Mimicking Alpha-1 Antitrypsin Deficiency
- Alpha-1 Antitrypsin Deficiency Emphysema
- Lymphoid Interstitial Pneumonia (LIP) in Sjogren's Syndrome
- Acute Exacerbation of Idiopathic Pulmonary Fibrosis Triggered by Minor Trauma