Differentiated thyroid cancer and outcome in iodine deficiency.

AIMS: Factors influencing prognosis and long-term outcome of thyroid cancer have been described by several groups. We wished to asses the previously described prognostic factors in a moderately iodine deficient region in Hungary. METHODS: Four hundred and fifty-four out of 492 patients who had surgery for papillary thyroid cancer (PTC, 386 cases) and follicular thyroid cancer (FTC, 106 cases) between 1971 and 1998 were analyzed. Survival curves were compared using the Kaplan-Meier method and Cox regression analysis. RESULTS: The 10 and 20-year survival rates were 87.9 and 84% for PTC, and 78.2 and 78.2% for FTC. In PTC, extrathyroidal invasion (p<0.0001), lymph node metastasis (p<0.0001), distant metastasis (p<0.0001), and age over 40 years (p=0.002) were significant adverse predictors. In FTC, extrathyroidal invasion (p=0.003) distant metastases (p<0.0001), and age over 40 years (p=0.011) were significant adverse predictors. CONCLUSION: Iodine intake did not appear to influence survival. The incidence of follicular cancer, which has less favourable prognosis, was higher in iodine deficient regions. This supports the importance of iodine supplementation in these areas.

[PET scanning in head and neck cancer] / Pozitronemissziós tomográfia a fej-nyaki tumorok diagnosztikájában.

INTRODUCTION: FDG (fluorine-labeled deoxy-glucose) and 11C-methionine positron emission tomography was evaluated in the diagnostics of head and neck cancer. PET scans were applied for identifying/staging relapse after oncotherapy or searching unknown primary tumor with metastatic lymph nodes of the neck. METHODS: Retrospective analysis of 22 patients examined by 17 (18)FDG and 15 (11)C-methionine PET scan. In 9 cases indication was unknown primary tumor with positive neck, in 13 cases previously treated head and neck cancer patients were examined for recurrence/restaging. RESULTS: In searching for unknown primary tumor not detectable with conventional methods, PET was effective in 22%, however, false positivity and uncertain results were found as well. In restaging PET proved to be very effective (85%) to discover recurrences and to differentiate them from post-treatment (mainly irradiation) effects. In two cases silent distant metastase were detected. CONCLUSION: PET can provide valuable information about unknown primary tumors, recurrences after oncotherapy and distant metastases as well. Simultaneous use of FDG/methionine scans does not improve the results.