Despite its advanced stage at presentation, pediatric thyroid cancer is associated with an excellent prognosis. We advocate total thyroidectomy and radioactive iodine as the best management option as the incidence of pulmonary metastases is high.

Recently, two research groups published numbers for D2 receptor sites in the neostriatum of drug-naive schizophrenic patients, obtained in vivo by positron emission tomography (PET). One study appeared to confirm the increase of D2 receptor numbers, while the other study did not. A workshop was convened in Montreal to examine the reasons for the discrepancy between the results obtained by the two groups. The workshop considered patient populations, PET instrumentation and scanning methods, pharmacology, and modeling. The workshop identified differences between the approaches of the two groups that could contribute to the divergent results, including age and chronicity of the patient samples, brain region selected for study, metabolism of the different radioligands in blood and brain, reversibility of binding, PET instrumentation, and complexity of data analysis. The workshop concluded that these initial efforts had made considerable progress in establishing the role of PET in the understanding of the biochemical processes underlying mental illness. In particular, the unique ability to quantify regional neuroreceptor density at different stages in the evolution of the disease has been implemented. At the same time, the work so far and this conference served to identify the main sources contributing to the different findings from the two centers. This information will be important in designing the next phase of the research which will build upon and reconcile these apparent discrepancies.

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The aim of this study was to determine whether or not a single dose of a beta-blocker, such as propranolol 40 mg, administered 60 min prior to (18)F-fluorodeoxyglucose ((18)F-FDG) injection would help reduce brown fat uptake of (18)F-FDG. Patients who were referred for either a pre-treatment or a post-treatment evaluation positron emission tomography (PET) scan and who showed (18)F-FDG uptake in brown adipose tissue (BAT) were included in this study. The total number of patients who showed uptake in BAT and in whom a repeat study was carried out after propranolol injection was 40. A repeat PET scan was carried out after an interval of at least 48 h. Propranolol at a dose of 40 mg was given orally 60 min prior to the (18)F-FDG injection. A whole-body PET scan was performed on a dedicated whole-body PET scanner (ADVANCE, GE Medical Systems, Milwaukee, WI), using attenuation correction with 68-Ge external pin sources. We observed that (18)F-FDG uptake in BAT was absent in 36 (90%) patients post propranolol. We conclude that propranolol reduces the uptake of (18)F-FDG in BAT, and thus improves the accuracy of PET imaging.