Radioiodine treatment for pediatric hyperthyroid Grave's disease.

Grave's disease (GD) is an autoimmune disease in which excessive amounts of thyroid hormones circulate in the blood. Treatment for pediatric GD includes (1) antithyroid drugs (ATD), (2) radioiodine, and (3) thyroidectomy. Yet, the optimal therapy remains controversial. We collected studies from all electronically available sources as well as from conferences held in China. All studies using radioiodine and/or ATD and/or thyroidectomy were included. Information was found on 1,874 pediatric GD patients treated with radioiodine, 1,279 patients treated with ATD and 1,362 patients treated surgically. The cure rate for radioiodine was 49.8%; the incidence of hypothyroidism, 37.8%; of relapse, 6.3%; of adverse effects, 1.55%; and of drop outs, 0.6%. These data show that radioiodine treatment is safe and effective in pediatric GD with significant lower incidence of relapse and adverse effects but significantly higher incidence of hypothyroidism as compared with both ATD and thyroidectomy. For the time being, radioiodine treatment for pediatric GD remains an excellent first-line therapy and a good second-line therapy for patients with ATD failure, severe complications, or poor compliance.

Iodine biokinetics and dosimetry in radioiodine therapy of thyroid cancer: procedures and results of a prospective international controlled study of ablation after rhTSH or hormone withdrawal.

UNLABELLED: Technical aspects and results of the dosimetric assessments of postoperative radioiodine ablation in the framework of an international, prospective, controlled, randomized, comparative study of the effectiveness of ablation therapy with 3.7 GBq (131)I in differentiated thyroid cancer after stimulation with recombinant human TSH (rhTSH) or by thyroid hormone withdrawal (THW) are presented. METHODS: Sixty-three patients were randomized after thyroidectomy to either the THW or the rhTSH group. Scintigraphic neck images were acquired starting 48 h after radioiodine administration to assess biokinetics in the thyroid remnant. The activity in blood samples was quantified and data from whole-body probe measurements and scintigraphic whole-body scans were combined to deduce retention curves in blood and whole body, respectively. The absorbed dose to the blood was calculated using a modified approach based on the formalism of the MIRD Committee of the Society of Nuclear Medicine. RESULTS: The effective half-time in the remnant thyroid tissue was significantly longer after rhTSH than THW (67.6 +/- 48.8 vs. 48.0 +/- 52.6 h, respectively; P = 0.01), whereas the observed differences of the mean 48-h (131)I uptakes (0.5% +/- 0.7% vs. 0.9% +/- 1.0% after THW; P = 0.1) and residence times (0.9 +/- 1.3 vs. 1.4 +/- 1.5 h after THW; P = 0.1) between the rhTSH and THW groups were not statistically significant. The specific absorbed dose to the blood was significantly (P <0.0001) lower after administration of rhTSH (mean, 0.109 +/- 0.028 mGy/MBq; maximum, 0.18 mGy/MBq) than after THW (mean, 0.167 +/- 0.061 mGy/MBq; maximum, 0.35 mGy/MBq), indicating that higher activities of radioiodine might be safely administered after exogenous stimulation with rhTSH. CONCLUSION: Indication of an influence of the residence time of radioiodine in the blood on the fractional uptake into thyroid remnant was found. A novel regimen is proposed in which therapeutic activities to be administered are determined from the individual specific blood dose.

Recombinant Human Thyroid Stimulating Hormone versus Thyroid Hormone Withdrawal for Radioactive Iodine Treatment of Differentiated Thyroid Cancer with Nodal Metastatic Disease.

Introduction. Recombinant human thyroid stimulating hormone (rhTSH) is approved for preparation of thyroid remnant ablation with radioactive iodine (RAI) in low risk patients with well differentiated thyroid cancer (DTC). We studied the safety and efficacy of rhTSH preparation for RAI treatment of thyroid cancer patients with nodal metastatic disease. Methods. A retrospective analysis was performed on 108 patients with histopathologically confirmed nodal metastatic DTC, treated with initial RAI between January 1, 2000, and December 31, 2007. Within this selected group, 31 and 42 patients were prepared for initial and all subsequent RAI treatments by either thyroid hormone withdrawal (THW) or rhTSH protocols and were followed up for at least 3 years. Results. The response to initial treatment, classified as excellent, acceptable, or incomplete, was not different between the rhTSH group (57%, 21%, and 21%, resp.) and the THW group (39%, 13%, and 48%, resp.; P = 0.052). There was no significant difference in the final clinical outcome between the groups. The rhTSH group received significantly fewer additional doses of RAI than the THW group (P = 0.03). Conclusion. In patients with nodal-positive DTC, preparation for RAI with rhTSH is a safe and efficacious alternative to THW protocol.

Is lower socioeconomic status associated with more advanced thyroid cancer stage at presentation? A study in two Canadian centers.

BACKGROUND: Some studies have shown a higher incidence of thyroid cancer in patients with insurance coverage and higher socioeconomic status (SES), and a higher thyroid cancer stage in patients with lower SES, suggesting SES-related health disparity in thyroid cancer. However, it is not known if the same is evident under a universal healthcare system such as that in Canada. METHODS: We used data from the Canadian Thyroid Cancer Consortium, a large thyroid cancer registry that collects data from two major thyroid cancer referral centers (London, Ontario, and Halifax, Nova Scotia). We included patients who presented with thyroid cancer between 1998 and 2011. We determined age at presentation, sex, and thyroid cancer status using the American Joint Committee on Cancer (AJCC) staging criteria. Individuals' postal codes were used to retrieve data from the Canadian census for the years 1996, 2001, and 2006 to approximate household income. Ordered logistic regression was used to determine odds ratios of presenting with more advanced stage thyroid cancer as they relate to income, age, and sex. RESULTS: We included 1701 patients: 1334 cases from London and 367 from Halifax. Thyroid cancer was diagnosed more frequently in the higher SES groups (p<0.001). Compared to patients in the top income quintile, patients in the lowest and second-lowest income quintiles had significantly higher odds of having more advanced stage thyroid cancer at presentation (OR 1.58, p=0.002; 1.37, p=0.024 respectively). CONCLUSIONS: Our study suggests that, similar to countries that lack a universal healthcare system, health disparity in thyroid cancer also exists in Canada. It appears that while thyroid cancers were diagnosed more frequently in Canadian patients of higher SES, Canadian patients in the lower SES groups had more advanced stage thyroid cancer at presentation.