A 77-year-old man with Metastatic lung cancer develops dyspnea and an unusual olive-brown pleural effusion. What is the key diagnostic test?
A 77-year-old man with metastatic lung adenocarcinoma presented to the emergency department with a 2-week history of dyspnea. Imaging studies showed a pleural effusion on the right side, previously known liver metastases and perihepatic fluid, and new intrahepatic dilatation of the biliary ducts. A chest tube was placed, and the color of the drained pleural fluid was olive brown. What additional pleural-fluid test is most likely to reveal the diagnosis?
What is the most likely diagnosis?
Bilirubin, Bilothorax, Dyspnea, Metastatic Cancer, Pleural Effusion
