Malignant chylothorax from mediastinal adenocarcinoma: management with VATS and thoracic duct ligation

Background: Malignant chylothorax is a rare pleural effusion caused by thoracic duct disruption, often due to mediastinal tumors. High-output effusions can cause malnutrition, immunosuppression, and delay cancer treatment. Case presentation: A 55-year-old male heavy smoker presented with dyspnea, dry cough, and pleuritic chest pain. Imaging revealed a mediastinal mass compressing the superior vena cava and a massive right-sided chylous pleural effusion. Thoracentesis and chest tube drainage yielded milky chyle. Due to the high-risk tumor location, video-assisted thoracoscopic surgery (VATS) was performed for biopsy and thoracic duct ligation. Postoperatively, the effusion resolved, and the patient was referred for systemic chemotherapy. Histopathology confirmed metastatic intermediate-grade adenocarcinoma (CK7-positive, TTF-1-negative). Discussion: High-output malignant chylothorax is challenging due to chyle loss and the involvement of major mediastinal vessels. Conservative therapy often fails, making early procedural intervention essential. VATS allows for safe biopsy and simultaneous thoracic duct ligation, minimizing morbidity. Conclusion: Prompt recognition and a multidisciplinary approach are crucial. VATS ligation effectively controls chyle leakage, reduces systemic complications, and enables timely oncologic therapy.