title: [Rol of thallium-201/gallium-67 cerebral tomogammography in the differential diagnosis of cerebral space occupying lesions].
abstract: BACKGROUND
  Central nervous system (CNS) neoplasms are 10% of all tumors. A metastasis of an unknown primary neoplasm should be suspected in an adult with a cerebral tumor. In this location, the origin of most of metastases (62%) is lung, breast, skin and kidney. However, a differentiation of CNS focal infection and brain tumor, based on clinical status and morphologic imaging, may be difficult. A positive Tl-201 next to a negative Ga-67 SPECT brain scans is entirely in accord with brain metastatic tumor.
  
  
  METHODS
  A 72-year-old man, with history of excised bladder cancer, was admitted for neurological symptoms associated with a left occipital mass demonstrated by cranial CT and brain MRI. Clinicoradiological findings suggested a neoplastic process. Two cerebral biopsies just showed inflammatory cells. Tl-201 and Ga-67 SPECT brain scans were performed and their findings, an abnormal uptake of Tl-201 in the left occipital cortex and a negative Ga-67 scan, favored a neoplastic process. Radical exeresis of the lesion showed a metastatic adenosquamous carcinoma of probably lung origin.
  
  
  CONCLUSIONS
  Tl-201 in addition to Ga-67 brain SPECT scans are a valuable tool for differential diagnosis between cerebral infection and brain tumour in patients with a sole cerebral mass lesion, especially when clinicoradiological findings and biopsy results are conflicting.
authors.affiliation: Servicio de Medicina Nuclear, Hospital Miguel Servet, Zaragoza, España. anabelcortes@iname.com
authors.forename: R
authors.initials: R
authors.lastname: Martínez-Lázaro
authors.forename: A
authors.initials: A
authors.lastname: Cortés
authors.forename: C
authors.initials: C
authors.lastname: Sáez
authors.forename: P
authors.initials: P
authors.lastname: Arazo
authors.forename: A
authors.initials: A
authors.lastname: Ascaso
mesh_terms: D000368:Aged; D001706:Biopsy; D001921:Brain / Q000473:pathology; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000556:secondary*; D018196:Carcinoma, Adenosquamous / Q000175:diagnosis* / Q000556:secondary*; D003937:Diagnosis, Differential; D005710:Gallium Radioisotopes; D006801:Humans; D008175:Lung Neoplasms / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D019275:Radiopharmaceuticals; D013794:Thallium Radioisotopes; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed
chemical_list: D005710:Gallium Radioisotopes; D019275:Radiopharmaceuticals; D013794:Thallium Radioisotopes
vernacular_title: Valor de la tomogammagrafía cerebral Talio-201/Galio-67 en el diagnóstico diferencial de las lesiones cerebrales ocupantes de espacio.