(1161) Curious Chylo: Chylothorax Caused by Rarely Metastatic Vulvar Cancer Lymphadenopathy

Introduction: Chylothorax is a rare but serious condition characterized by the accumulation of milky lymphatic fluid in the pleural space. Nontraumatic chylothorax due to malignancy is usually caused by lymphomas. Vulvar carcinoma is a less common gynecologic malignancy, and is usually diagnosed at an early stage, with less than 6% of cases presenting with distant metastasis. Here we present a case of a 76-year-old with massive chylothorax due to metastatic vulvar carcinoma.

Description: A 76-year-old woman with prior history of vulvar squamous cell carcinoma (SCC) status post partial vulvectomy on carboplatin and paclitaxel who was recently found to have metastatic disease following a supraclavicular lymph node biopsy presented to the emergency department with shortness of breath. She was found to have bulky mediastinal, hilar, and supraclavicular lymphadenopathy on computerized tomography (CT) scan, with a new large partially loculated right pleural effusion with compression of the right middle and lower lobe. The patient was admitted, and a thoracocentesis was performed with drainage of 1 liter of milky pleural fluid. Analysis revealed triglyceride level of 1328 and fluid cytology was negative for malignancy. The patient underwent video-assisted thorascopic partial pleurectomy, talc pleurodesis, and therapeutic wedge resection of the right middle lobe. Pathology results of the pleura and right middle lung were negative for malignancy. The patient was discharged on a low-fat diet to a post-acute facility with chest tubes in place, 8 days after the procedure.

Discussion: Two-thirds of chylothorax due to malignancy are caused by lymphomas, either through compression of lymphatic channels by enlarged lymph nodes in the mediastinum and hilum or by the infiltration of cancer cells into the thoracic duct. The latter is less likely in our patient’s case, as cytology of the pleural fluid was negative for malignancy. It is important to properly evaluate the etiology of new pleural effusions in an otherwise healthy patient, as chylothorax is the presenting symptom of malignancy in some cases. To our knowledge, this is the first case reported of chylothorax resulting from bulky lymphadenopathy caused by squamous cell carcinoma of the vulva, which very rarely metastasizes distantly.