A Milky Mystery: Chylothorax Unmasking Non-Hodgkin Lymphoma.

Chylothorax is an uncommon cause of pleural effusion that presents diagnostic and therapeutic challenges. We report the case of a 71-year-old woman who presented with shortness of breath and abdominal distension for one week. Thoracic imaging revealed a large left-sided pleural effusion. A thoracentesis drained 1 liter of turbid, milky fluid, and pleural fluid analysis confirmed an exudative effusion with a triglyceride level of 1199 mg/dL. Cytology identified CD markers (CD10, CD19, CD20) consistent with stage IV follicular lymphoma. The patient was treated with six cycles of R-CHOP (rituximab, vincristine, cyclophosphamide, and prednisone) chemotherapy and required a pleurX catheter for recurrent effusions, achieving partial symptomatic control. This case highlights malignant chylothorax as a rare clinical presentation of non-Hodgkin lymphoma and underscores the importance of a multidisciplinary approach in diagnosis and management. To our knowledge, this represents a rare instance of follicular lymphoma initially manifesting as chylothorax.