Comparative value of thallium and glucose SPECT imaging in childhood brain tumors

Thallium-201 chloride (Tl-201) single-photon emission computed tomography (SPECT) detects a high percentage of histologically and anatomically diverse pediatric brain tumors. Thallium-201 chloride SPECT and F-18 fluoro-deoxy-glucose (F-18-FDG) positron emission tomography (PET) are the most commonly used radionuclide techniques in neuro-oncology, Having developed a methodology to image F-18-FDG with SPECT, the authors performed SPECT scans coupled with magnetic resonance imaging to assess the comparative sensitivity of Tl-201 and F-18-FDG in 19 children with brain tumors. Tumors were detected using Tl-201 SPECT in 14 of 19 patients. Five of five postoperative residual tumors were detected by Tl-201 SPECT, and six of seven after irradiation recurrences were detected, F-18 fluoro-deoxy-glucose SPECT detected tumors in only three of 19 patients, all of whom had abnormal Tl-201 studies (all three after therapy recurrences). Thallium-201 chloride SPECT could be interpreted in 18 of 19 patients without magnetic resonance imaging confirmation, but none of the 19 F-18-FDG SPECT studies could be interpreted without magnetic resonance imaging. Thallium-201 chloride SPECT is more sensitive than F-18-FDG SPECT in the detection of primary or recurrent childhood brain tumors. The failure of F-18-FDG SPECT in follow-up after therapy is primarily a problem of limited fluoro-deoxy-glucose uptake, not spatial resolution. Thallium-201 chloride SPECT is a promising imaging modality in neurooncology. (C) 1998 by Elsevier Science Inc. All rights reserved.