title: The importance of identifying the unidentified tumor.
mesh_terms: D000368:Aged; D001012:Aorta, Abdominal / Q000000981:diagnostic imaging; D003937:Diagnosis, Differential; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis; D008228:Lymphoma, Non-Hodgkin / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D008297:Male; D009362:Neoplasm Metastasis / Q000175:diagnosis*; D010996:Pleural Effusion / Q000209:etiology; D011859:Radiography; D012077:Renal Artery / Q000000981:diagnostic imaging; D012186:Retroperitoneal Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery