Chylothorax as a Rare Complication of Chronic Lymphocytic Leukemia in a Filipino patient

Introduction/Background/Significance: Chronic Lymphocytic Leukemia (CLL), a common adult leukemia in Western population remains exceptionally rare among Asians, particularly Filipinos. More so, chylothorax as an initial or evolving complication of CLL without significant lymphocytosis and prominent lymphadenopathy is extremely uncommon, with limited cases reported globally. The mechanisms are often related to cell sludging and massive lymphadenopathy causing thoracic duct obstruction.

Materials and Methods/Case Presentation/Objective: This is the case of a 75-year-old Filipino male with an incidental diagnosis of CLL based on radiologic findings of pulmonary nodules and lymphadenopathy on routine pre operative clearance work up. Over a 10-month observation period, he developed exertional dyspnea associated with progressive dyspnea. Imaging revealed a right-sided pleural effusion. Diagnostic thoracentesis confirmed exudative chylothorax with pleural triglycerides of 556.7 mg/dL. Video-assisted thoracoscopic surgery (VATS) with pleurodesis was performed, and histopathologic evaluation showed no malignant pleural involvement. PET-CT demonstrated conglomerated, low-FDG-avid mediastinal lymph nodes suggestive of thoracic duct obstruction below T5. The patient was managed with total parenteral nutrition (TPN), followed by targeted CLL therapy with Ibrutinib and later Venetoclax, achieving resolution of the chylothorax and clinical improvement.

Results/Description/Main Outcome Measures: This case highlights a rare complication of CLL, where thoracic duct compression led to chylothorax as a manifestation of disease activity. It emphasizes the importance of recognizing non-infectious pleural effusions in CLL and the utility of a multimodality approach involving fluid analysis and imaging in the diagnosis and evaluation of treatment response with targeted therapy.

Conclusions: Chylothorax should be considered in the differential diagnosis of pleural effusion in CLL patients while watching and waiting. Early diagnosis and integrated management can result in favorable outcome. This case adds to the limited literature on CLL-related chylothorax and serves as a reference for similar presentations in low-incidence populations.