Nivolumab-Induced Chylothorax in A Patient with Advanced Gastric Adenocarcinoma

Chylothorax refers to the presence of chyle in the pleural space leading to respiratory compromise. Chylothorax secondary to gastric adenocarcinoma or immune checkpoint inhibitors, such as nivolumab, is exceedingly rare and has been documented only in isolated case reports. The exact mechanism by which nivolumab may induce chylothorax remains unclear, though immune-mediated increased lymphatic permeability induced by anti-PD-1 has been hypothesised. This report highlights a unique presentation of chylothorax in a patient with gastric adenocarcinoma undergoing nivolumab therapy.

Chylothorax can be a rare immune-related adverse event of nivolumab.In differentiating between malignant chylothorax in advanced malignancy and immune-related adverse events, chylothorax can be difficult. Negative pleural cytology, lack of thoracic duct obstruction and response to immunotherapy can guide clinicians in attributing the cause, which is essential for making decisions about continuing or discontinuing immunotherapy.