The onset time of amiodarone-induced thyrotoxicosis (AIT) depends on AIT type

Objective: Considering the different pathogenic mechanisms of the two main forms of amiodarone-induced thyrotoxicosis (AIT), we ascertained whether this results in a different onset time as well. Design and methods: We retrospectively analyzed the clinical records of 200 consecutive AIT patients (157 men and 43 women; mean age 62.2G12.6 years) referred to our Department from 1987 to 2012. The onset time of AIT was defined as the time elapsed from the beginning of amiodarone therapy and the first diagnosis of thyrotoxicosis, expressed in months. Factors associated with the onset time of AIT were evaluated by univariate and multivariate analyses. Results: The median onset time of thyrotoxicosis was 3.5 months (95% CI 2–6 months) in patients with type 1 AIT (AIT1) and 30 months (95% CI 27–32 months, P!0.001) in those with type 2 AIT (AIT2). Of the total number of patients, 5% with AIT1 and 23% with AIT2 (PZ0.007) developed thyrotoxicosis after amiodarone withdrawal. Factors affecting the onset time of thyrotoxicosis were the type of AIT and thyroid volume (TV). Conclusions:ThedifferentpathogenicmechanismsofthetwoformsofAITaccountfordifferentonsettimesofthyrotoxicosisin the two groups. Patients with preexisting thyroid abnormalities (candidate to develop AIT1) may require a stricter follow-up during amiodarone therapy than those usually recommended. In AIT1, the onset of thyrotoxicosis after amiodarone withdrawal is rare, while AIT2 patients may require periodic tests for thyroid function longer after withdrawing amiodarone

A special case of bilateral ovarian metastases in a woman with papillary carcinoma of the thyroid

Papillary thyroid carcinoma is a slow growing tumor with low metastatic potential. The most frequent sites of distant metastases are lung and bone; less frequent sites are brain, liver, kidney, and skin. Ovarian metastases from papillary thyroid carcinoma are exceptional. We describe a case of bilateral ovarian metastases from a papillary thyroid carcinoma associated with autoimmune thyroiditis in a 38-year-old woman who underwent thyroidectomy and cervical lymph-node dissection 7 years before, followed by 948 mCi of 131I. A primary ovarian cancer could be excluded by the typical pathological aspects of a papillary thyroid carcinoma in a context of an aggressive form of thyroid cancer. On the other hand, the clinical history and the absence of normal thyroid epithelium and teratomatous components could exclude a papillary thyroid carcinoma arising in struma ovarii. This is a singular case of papillary thyroid carcinoma metastasizing to the ovary, combined with an autoimmune thyroiditis