Incidental primary mediastinal choriocarcinoma diagnosed by endobronchial ultrasound-guided fine needle aspiration in a patient presenting with transient ischemic attack and stroke.

We describe a case of a 41-year old male patient with no significant prior medical history who presents with symptoms of Transient Ischemic Attack and stroke. Magnetic Resonance Imaging (MRI) of the brain identified areas of ischemia in the left side, and angiography showed occlusion of the left Medial Cerebral Artery (MCA). Cardiac Transthoracic Echocardiogram (TTE) for stroke evaluation incidentally noted a mediastinal abnormality leading to cancer work-up. Computer Tomography (CT) and 18 F-fluorodeoxyglucose (FDG) PET-CT scan of the chest incidentally revealed an avid 6 cm paraesophagial/subcarinal mass. Further diagnostic work-up with endoscopic and endobronchial ultra sound (EBUS)-guided fine needle aspiration (FNA) of the mass yielded a cytology diagnosis of Germ Cell Tumor (GCT), with choriocarcinoma component. Additionally, high plasma levels of β-human chorionic gonadotrophin (β-HCG) were detected with no evidence of testicular tumor. This exceedingly rare presentation for a primary mediastinal choriocarcinoma underscores the importance of complete investigation of young patients presenting with neurological symptoms compatible with ischemic events. Diagn. Cytopathol. 2017;45:738-743.