[Rol of thallium-201/gallium-67 cerebral tomogammography in the differential diagnosis of cerebral space occupying lesions].
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.
Martínez-Lázaro
R
R
Servicio de Medicina Nuclear, Hospital Miguel Servet, Zaragoza, España. anabelcortes@iname.com
Cortés
A
A
Sáez
C
C
Arazo
P
P
Ascaso
A
A
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
D005710:Gallium Radioisotopes; D019275:Radiopharmaceuticals; D013794:Thallium Radioisotopes
Valor de la tomogammagrafía cerebral Talio-201/Galio-67 en el diagnóstico diferencial de las lesiones cerebrales ocupantes de espacio.