Incidental scintigraphic finding of ovarian teratoma containing normal thyroid tissue on post-radioactive iodine therapy for papillary thyroid cancer.

Abnormal focal uptakes are often visualized on I post-treatment scintigraphy in case of differentiated thyroid carcinoma. For some of these, especially on atypical localization, it can be difficult to affirm the benign or malignant nature. A high serum thyroglubulin value after surgery may suggest the presence of metastatic disease. We report a case of an abnormal ovarian uptake on post-treatment scintigraphy associated with an elevated thyroglobulin value revealing finally an ovarian mature cystic teratoma containing normal thyroid tissue.

Thoracic 131I uptake after previous pneumonectomy in patients treated for differentiated thyroid cancer.

In patients treated for differentiated thyroid cancer with radioiodine (131I), abnormal uptake on post-therapeutic whole-body scan may lead to repeated administration of 131I. Uptake not linked to thyroid cancer but to other conditions should be recognized so that patients are not overtreated. We describe 3 cases of unilateral thoracic 131I uptake in patients previously treated by pneumonectomy for lung cancer, without evidence of persistent lung cancer.

Strategies of radioiodine ablation in patients with low-risk thyroid cancer.

BACKGROUND: It is not clear whether the administration of radioiodine provides any benefit to patients with low-risk thyroid cancer after a complete surgical resection. The administration of the smallest possible amount of radioiodine would improve care. METHODS: In our randomized, phase 3 trial, we compared two thyrotropin-stimulation methods (thyroid hormone withdrawal and use of recombinant human thyrotropin) and two radioiodine ((131)I) doses (i.e., administered activities) (1.1 GBq and 3.7 GBq) in a 2-by-2 design. Inclusion criteria were an age of 18 years or older; total thyroidectomy for differentiated thyroid carcinoma; tumor-node-metastasis (TNM) stage, ascertained on pathological examination (p) of a surgical specimen, of pT1 (with tumor diameter ≤1 cm) and N1 or Nx, pT1 (with tumor diameter >1 to 2 cm) and any N stage, or pT2N0; absence of distant metastasis; and no iodine contamination. Thyroid ablation was assessed 8 months after radioiodine administration by neck ultrasonography and measurement of recombinant human thyrotropin-stimulated thyroglobulin. Comparisons were based on an equivalence framework. RESULTS: There were 752 patients enrolled between 2007 and 2010; 92% had papillary cancer. There were no unexpected serious adverse events. In the 684 patients with data that could be evaluated, ultrasonography of the neck was normal in 652 (95%), and the stimulated thyroglobulin level was 1.0 ng per milliliter or less in 621 of the 652 patients (95%) without detectable thyroglobulin antibodies. Thyroid ablation was complete in 631 of the 684 patients (92%). The ablation rate was equivalent between the (131)I doses and between the thyrotropin-stimulation methods. CONCLUSIONS: The use of recombinant human thyrotropin and low-dose (1.1 GBq) postoperative radioiodine ablation may be sufficient for the management of low-risk thyroid cancer. (Funded by the French National Cancer Institute [INCa] and the French Ministry of Health; ClinicalTrials.gov number, NCT00435851; INCa number, RECF0447.).