methimazole and Struma-Ovarii

We report a rare case of Graves' disease associated with struma ovarii. A 26-year-old Japanese woman had preexisting Graves' disease and was positive for TSH receptor antibody. She had been on antithyroid medication at presentation. She noted a mass in the lower left abdomen, which was diagnosed as a left struma ovarii by radiological work-up including computed tomography, magnetic resonance imaging and scintigraphy. The surgically excised teratomatous tumor, containing cystic spaces with thyroid tissue, was histologically proved to be struma ovarii. Since thyroid function tests and TSH receptor antibody did not change after surgery, her hyperthyroidism was considered to be due to Graves' disease. Our case was diagnosed as struma ovarii before surgery using various imaging studies.

Topics: Adult; Antithyroid Agents; Autoantibodies; Female; Graves Disease; Humans; Immunoglobulins, Thyroid-Stimulating; Magnetic Resonance Imaging; Methimazole; Ovarian Neoplasms; Ovariectomy; Radionuclide Imaging; Receptors, Thyrotropin; Struma Ovarii; Thyroid Hormones; Tomography, X-Ray Computed; Ultrasonography

We report the case of a 61-year-old woman with persistent thyrotoxicosis for 7 years despite low thyroidal radioiodine uptake and methimazole treatment. Her initial I whole-body scan (WBS) was read as negative. Upon evaluation in our institution, she remained hyperthyroid after discontinuation of methimazole. Repeat WBS with SPECT/CT revealed low 24-hour thyroidal uptake (RAIU = 2%) and intensely focal radioiodine uptake in a large heterogeneous left pelvic mass, consistent with left adnexal struma ovarii. Resection of this mass confirmed benign struma ovarii. This case illustrates the advantage of fusion SPECT/CT imaging with planar I-WBS for diagnosis of extrathyroidal thyrotoxicosis.

Topics: Female; Humans; Iodine Radioisotopes; Methimazole; Middle Aged; Single Photon Emission Computed Tomography Computed Tomography; Struma Ovarii; Thyrotoxicosis; Whole Body Imaging

Coexisting of Graves' disease and functioning struma ovarii is a rare condition. Although the histology of struma ovarii predominantly composed of thyrocytes, the majority of the patients did not have thyrotoxicosis. The mechanism underlying the functioning status of the tumor is still unclear but the presence of thyroid stimulating hormone receptor (TSHR) is thought to play a role. Here we describe the patient presentation and report the TSHR expression of the tumor.. A 56-year old Asian woman presented with long standing thyrotoxicosis for 23 years. She was diagnosed with Graves' disease and thyroid nodules. She had bilateral exophthalmos and had high titer of plasma TSHR antibody. Total thyroidectomy was performed and the histologic findings confirmed the clinical diagnosis. The patient had persistent thyrotoxicosis postoperatively. Thyroid uptake demonstrated the adequacy of the thyroid surgery and the whole body scan confirmed the presence of functioning thyroid tissue at pelvic area. The surgery was scheduled and the patient had hypothyroidism after the surgery. The pathological diagnosis was struma ovarii at right ovary. We performed TSHR staining in both the patient's struma ovarii and in 3 cases of non-functioning struma ovarii. The staining results were all positive and the intensity of the TSHR staining of functioning struma ovarii was the same as that in other cases of non-functioning tumors, suggesting that the determinant of functioning struma ovarii might be the presence of TSHR stimuli rather than the intensity of the TSHR in the ovarian tissue.. In patients with Graves' disease with persistent or recurrent thyrotoxicosis after adequate ablative treatment, the possibility of ectopic thyroid hormone production should be considered. TSHR expression is found in patients with functioning and non-functioning struma ovarii and cannot solely be used to determine the functioning status of the tumor.

Topics: Antithyroid Agents; Female; Graves Disease; Humans; Hysterectomy; Methimazole; Middle Aged; Ovarian Neoplasms; Ovariectomy; Salpingectomy; Struma Ovarii; Thyroidectomy; Thyrotoxicosis; Treatment Outcome

Struma ovarii is the most common monodermal ovarian teratoma and consists mainly of thyroid tissue. Only 5% of patients with this tumor have features of hyperthyroidism. The pathophysiology of hyperthyroidism in struma ovarii is not clear.. We describe a case of benign struma ovarii, presenting with the clinical features of an ovarian cancer: large complex pelvic mass, large amount of ascites and markedly elevated CA-125 serum levels. The patient was initially treated for Graves' disease, on the basis of ultrasonographic, laboratoristic and scintigraphic evidence. The resistance to the medical treatment led to thyroidectomy. After surgery the hyperthyroidism persisted and, suddenly, the patient presented ascites. A large pelvic mass was then diagnosed which, at the pathologic examination, was diagnosed as a struma ovarii.. The struma ovarii always has to be considered when a pelvic mass is associated with features of hyperthyroidism.

Topics: Adult; Ascites; CA-125 Antigen; Female; Graves Disease; Humans; Hyperthyroidism; Methimazole; Ovarian Neoplasms; Ovariectomy; Struma Ovarii; Thyroidectomy; Thyroxine