Acute Pazopanib-Associated Interstitial Lung Disease in a Patient With Ulcerative Colitis and Metastatic Sarcoma: A Case Report.

Pazopanib is used in the treatment of advanced renal cell carcinoma and soft tissue sarcoma. While pneumothorax is a recognized pulmonary complication, interstitial lung disease (ILD) typically occurs after months of therapy. We present a rare case of acute onset ILD occurring within 72 hours of initiating pazopanib in a 43-year-old male with metastatic sarcoma and a history of ulcerative colitis. The patient developed rapidly progressive hypoxemic respiratory failure shortly after starting pazopanib. Extensive infectious and autoimmune workups were negative. Imaging findings, combined with a favorable clinical response to corticosteroids, supported the diagnosis of drug-induced ILD (DILD). The clinical course was further complicated by a persistent right-sided pneumothorax and ultimately fatal respiratory failure. This case highlights the potential for acute pazopanib-associated ILD, particularly in patients with predisposing risk factors.