Rare Metastatic Sites of a Lung Adenocarcinoma

We report a rare case of a lung adenocarcinoma presenting with chylothorax and metastases to the common bile duct and the rectum. From the radiological and endoscopic appearance of the tumors, the main differential diagnoses were metastatic lung cancer to multiple rare extra-thoracic sites and multiple synchronous primary oncological malignancies. Pathological examination of the biopsies with positive immunohistochemical staining for thyroid transcription factor-1 (TTF-1) played an important role in confirming metastatic pulmonary adenocarcinoma.