title: Retroperitoneal extragonadal germ cell tumor diagnosed by needle aspiration cytology and electron microscopy.
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001707:Biopsy, Needle; D006801:Humans; D008297:Male; D008854:Microscopy, Electron; D009373:Neoplasms, Germ Cell and Embryonal / Q000175:diagnosis* / Q000648:ultrastructure; D012186:Retroperitoneal Neoplasms / Q000175:diagnosis* / Q000648:ultrastructure