Hürthle cell Thyroid Carcinoma Presenting as A “Hot” Nodule

ObjectiveTo report an unusual clinical scenario and a rare histopathologic finding of Hürthle cell thyroid carcinoma in a patient with an autonomous thyroid nodule.MethodsWe describe the presentation and clinical course leading to the surprising histopathologic diagnosis of Hürthle cell carcinoma in a pediatric patient who was diagnosed with hyperthyroidism presenting as a solitary toxic nodule.ResultsA 13-year-old white girl presented with a recent history of a palpable thyroid nodule during a routine primary care clinic visit. She was asymptomatic, and thyroid function tests revealed a suppressed thyrotropin concentration, high-normal free thyroxine concentration, and elevated triiodothyronine concentration. The patient underwent dedicated thyroid ultrasonography revealing a 3.5-cm complex mass in the left lobe with increased central vascularity. Iodine 123 imaging of the thyroid demonstrated homogenous, hyperintense activity in the left lobe. The right lobe was not visualized. A solitary toxic nodule was diagnosed, and, considering her age, she was referred for surgical management. The patient underwent a left lobectomy with isthmusectomy. Pathologic examination revealed a 5-cm, encapsulated, well-differentiated Hürthle cell carcinoma with negative margins and no lymphovascular invasion. The patient underwent subsequent completion thyroidectomy with no evidence of residual carcinoma in the right thyroid lobe.ConclusionsMalignancy in autonomously functioning thyroid nodules is rare. Most of the thyroid nodules presenting as “hot” on radioiodine scintigraphy are benign follicular adenomas. However, this case represents a rare clinical entity, and it highlights the need for clinicians to be vigilant and aware that occasionally carcinomas can masquerade as scintigraphic “hot” nodules. (Endocr Pract. 2011;17:e68-e72)     

A case of Graves' disease associated with an autonomously functioning thyroid nodule (AFTN) (Marine-Lenhalt syndrome) which spontaneously became a cold nodule

We report a 31-year-old female with Graves' disease associated with an autonomously functioning thyroid nodule (AFTN) (Marine-Lenhalt syndrome) in which the AFTN spontaneously became a cold nodule. Initially the patient was thyrotoxic and had diffuse goiter with an elevated radioiodine uptake. She became euthyroid following six months of antithyroid drug therapy, and in addition to diffuse goiter, the solitary hot nodule was palpable in the left lobe. Fourteen months later, hyperthyroidism recurred and the thyroid scan revealed diffuse radioiodine uptake with a cold area in the nodular region. The resected nodule showed extensive degeneration and the histological diagnosis was follicular adenoma with Graves' disease. We discussed the significance of recognizing the syndrome and also compared the frequency of spontaneous degeneration in AFTN and in solitary cold nodules.     

Parathyroidectomy-Induced Thyroiditis

ObjectiveTo highlight the possibility of development of thyroiditis after parathyroidectomy.MethodsClinical and laboratory findings in 2 cases are presented, and the relevant literature is reviewed.ResultsIn 2 women (84 years old and 55 years old) with no history of thyroid disease in one of them and a remote history of excision of a follicular adenoma in the other, thyrotoxicosis developed a few days to a week after parathyroidectomy for primary hyperparathyroidism. The first patient underwent bilateral cervical exploration with removal of a right inferior parathyroid adenoma, whereas the second patient had excision of 3¹/₂ parathyroid glands for 4-gland hyperplasia and 2 benign nodules from the left thyroid lobe. Both surgical procedures were uncomplicated. Neither patient had received any iodinated contrast agents or medications such as lithium or amiodarone before presentation. Laboratory results showed elevated levels of free thyroxine, suppressed thyroid-stimulating hormone levels, very low radioiodine uptake (in the second patient), and an elevated thyroglobulin level (in the first patient). Both patients were treated symptomatically with β-adrenergic antagonists. Thyroid function normalized and symptoms diminished after 1 to 2 months.ConclusionParathyroidectomy-induced thyroiditis is underrecognized. The majority of patients are asymptomatic, although clinically significant thyrotoxicosis can also occur. Candidates for parathyroidectomy should be informed of this potential complication, and thyroid function should be assessed if clinically indicated. (Endocr Pract. 2010;16:656-659)     

Subacute thyroiditis manifesting as a thyroid mass, vocal cord paralysis, and hypercalcemia

ObjectiveTo report a case of subacute thyroiditis manifesting as a thyroid mass, vocal cord paralysis, and hypercalcemia.MethodsWe describe the clinical, laboratory, and radiologic findings in a patient with an unusual clinical course of subacute thyroiditis.ResultsA 65-year-old woman presented with a hoarse voice and an enlarging tender mass in the right side of the neck. On admission, thyroid function was consistent with thyrotoxicosis from subacute thyroiditis. Laboratory studies showed a corrected serum calcium concentration of 11.4 mg/dL, intact parathyroid hormone of 125 pg/mL, 25-hydroxyvitamin D of 12 ng/mL, and creatinine of 1.8 mg/dL. Computed tomography of the neck without use of a contrast agent showed a heterogeneous mass in the right side of the neck in conjunction with deviation of the trachea from right to left but without invasion of the trachea. Thyroid ultrasonography disclosed a heterogeneous mass in the right thyroid lobe measuring 4.7 cm by 5.5 cm by 4.5 cm. Flexible laryngoscopy revealed right vocal cord paralysis. Treatment with a course of prednisone yielded normalization of the serum calcium level, improvement in her voice, and a decrease in size of the thyroid mass. Four months after initial presentation of the patient, thyroid hormone levels became normal, she was clinically euthyroid, and she had a full recovery of her voice. Her serum calcium concentration was normal (9.8 mg/dL) in association with a near-normal parathyroid hormone level of 90 pg/mL. The 25-hydroxyvitamin D and creatinine values were also normal. Repeated thyroid ultrasonography showed a smaller right thyroid lobe with a dominant nodule measuring 2.0 cm by 1.3 cm by 1.4 cm in the right upper pole.ConclusionThis case illustrates that subacute thyroiditis can have the unusual initial manifestations of a thyroid mass, vocal cord paralysis, and hypercalcemia. In similar patients, a trial of corticosteroid therapy may be warranted in an effort to improve clinical symptoms and thus avoid unnecessary surgical treatment. (Endocr Pract. 2012;18:e17-e20)     

Simultaneous occurrence of medullary and papillary carcinoma of the thyroid gland identified by fine needle aspiration. A case report

BACKGROUND: Fine needle aspiration (FNA) diagnosis of simultaneous medullary and papillary thyroid carcinoma in independent thyroid lobes is exceedingly rare. CASE: A 36-year-old female presented with a one-month history of dysphagia. Thyroid ultrasound revealed a multinodular goiter. She was clinically and biochemically euthyroid. FNA of the right thyroid nodule was consistent with medullary carcinoma, and FNA of the left thyroid lobe was consistent with papillary carcinoma. Immunohistochemistry revealed strong calcitonin and CEA positivity in the right lobe and lack of staining in the left lobe. Conversely, staining for thyroglobulin was negative on the right lobe and positive on the left lobe. CONCLUSION: The patient developed tumors in separate lobes of the thyroid. Immunoreactivity of calcitonin, CEA and thyroglobulin made a sharp distinction between the two tumors. Therefore, we conclude that these tumors were not linked by either embryology or genetics.     

Highly sensitive immunoradiometric assay for TSH and thyroid radioiodine uptake as predictors of thyroid suppression test

Suppression of TSH and thyroid radioiodine uptake by doses of either T4 or T3 were compared in 33 patients in whom Graves' thyrotoxicosis had been treated with thioamide drugs and the medication was discontinued for at least 4 months. Thyroidal radiodine uptake was suppressed in 19 patients and was not suppressed in the remaining 14 patients. Basal TSH levels before suppression were 2.07 microU/ml in the former, significantly exceeding those of the latter (0.91 microU/ml). A TSH level of at least 1.2 microU/ml before suppression is a good predictor of positive thyroid radioiodine suppression with a predictive value of 76%. A level lower than 0.7 microU/ml before suppression is a good predictor of negative thyroid radioiodine uptake suppression with a predictive value of 89%. The determination of TSH levels before the thyroid suppression test was helpful in predicting the result, but there were limitations. In the thyroid suppression test positive group, circulating T4 was depressed by doses of T3. In them, the magnitude of T4 depression correlated with the levels of thyroid radioiodine uptake before suppression. The levels of TSH correlated neither to changes in T4 nor to those in thyroid radioiodine uptake. This indicates that the thyroid glands which show high radioiodine uptake are sensitive to TSH and are also sensitive to suppression. The elevated sensitivity to TSH probably warrants the disappearance of abnormal thyroid stimulation more precisely.     

Unusual Initial Manifestation of Metastatic Follicular Carcinoma of the Thyroid with Thyrotoxicosis Diagnosed by Technetium Tc 99m Pertechnetate Scan: Case Report and Review of Literature

ObjectiveTo report a case of metastatic thyroid cancer diagnosed on a technetium Tc 99m pertechnetate (TcO₄^–) thyroid scan.MethodsWe present the clinical findings, laboratory results, imaging studies, and surgical pathology report in a man with thyrotoxicosis in whom metastatic well-differentiated thyroid cancer was diagnosed incidentally on a routine TcO₄ ^– thyroid scan in the setting of a presumed diagnosis of benign toxic thyroid disease. In addition, we review the literature regarding coexistence of metastatic thyroid cancer and thyrotoxicosis.ResultsA 68-year-old man with thyrotoxicosis was referred for radioiodine therapy. A routine TcO₄^- thyroid scan revealed high-grade extrathyroidal uptake in the right upper hemithorax as well as in the left side of the thorax. In view of this finding, radioiodine treatment was deferred; further imaging with computed tomography revealed a 6.5-cm mass in a rib on the right side. A biopsy of the rib confirmed the presence of metastatic follicular carcinoma of the thyroid. Scintigraphy revealed sites of metastatic involvement predominantly in the bones along with a cold nodule in the left thyroid lobe, consistent with the primary tumor.ConclusionThis case emphasizes the impact of scintigraphic findings on determining the correct management of a patient who would have otherwise undergone inappropriate treatment. Through an extensive literature review, the incidence of malignant involvement in hyperfunctioning thyroid glands and the possible role of sodium iodide symporter expression by thyroid cancer metastatic lesions in preoperative detection of metastatic sites are addressed. (Endocr Pract. 2009;15:458-462)     

Diagnostic Fine-Needle Aspiration Biopsy of an Intrathyroidal Parathyroid Gland and Subsequent Eucalcemia in a Patient with Primary Hyperparathyroidism

ObjectiveTo present the clinical course of a patient with persistent primary hyperparathyroidism (PHPT) whose intrathyroidal parathyroid gland was diagnosed by ultrasound-guided fine-needle aspiration biopsy (FNAB).MethodsWe describe the clinical course and laboratory, radiographic, and microscopic findings of a patient with persistent PHPT due to an intrathyroidal cystic parathyroid gland and review the relevant literature.ResultsA 74-year-old man with PHPT (presenting serum calcium concentration, 16.2 mg/dL; intact parathyroid hormone [PTH] concentration, 341 pg/mL) had surgical excision of the right superior, right inferior, and left inferior parathyroid glands, but the left superior parathyroid gland remained unidentified. Microscopic examination revealed parathyroid hyperplasia. Technetium Tc 99m sestamibi single-photon emission computed tomography imaging showed uptake in 2 foci, 1 on each side of midline in the neck. Reoperation with attention to the left neck failed to locate another parathyroid gland. Neck ultrasonography demonstrated a complex nodule within the right lower lobe of the thyroid. Results from FNAB of the solid component were consistent with parathyroid cells, and cystic fluid PTH concentration was greater than 1800 pg/mL. Nine months later, neck ultrasonography showed a hypoechoic area located posterior to the inferior pole of the right thyroid. The patient remained eucalcemic 16 months postprocedure.ConclusionAutoinfarction of the parathyroid gland and aspiration of cystic fluid may explain resolution of hypercalcemia. Although PHPT due to functioning parathyroid cysts is rare, and PHPT due to cystic parathyroid hyperplasia has been described, this is the first case report of a patient with persistent PHPT due to a functional parathyroid cyst whose diagnosis by FNAB was followed by eucalcemia. (Endocr Pract. 2008;14:80-86)     

Incidental Radiologic Finding of an Anterior Superior Mediastinal Mass Masquerading as Metastatic Thyroid Cancer in Patients with Treated Thyroid Cancer

ObjectiveTo demonstrate that an anterior superior mediastinal mass on radiologic imaging may represent an incidental finding and not metastases in patients with a history of treated well-differentiated thyroid cancer.MethodsWe report the clinical presentation and outcomes of 4 patients with a history of thyroid cancer who were incidentally found to have anterior superior mediastinal masses on imaging. We also review the relevant literature.ResultsFour young adults with a history of stage I papillary thyroid cancer treated with total thyroidectomy and radioiodine were incidentally found to have thymic enlargement on imaging studies within a 3-year posttreatment window. In each case, this enlargement was believed to be secondary to thymic hyperplasia and not metastatic disease, and each patient has exhibited a benign clinical course. Review of the literature revealed few reports of an association between thymic hyperplasia and thyroid cancer.ConclusionsThymic hyperplasia may be discovered on posttreatment imaging studies in patients with a history of well-differentiated thyroid cancer, particularly in young adults who have received radioiodine therapy. Recognition of the possible coexistence of this incidental finding in patients with thyroid cancer may help to avoid unnecessary invasive procedures and treatments. (Endocr Pract. 2011;17:65-69)     

Graves' hyperthyroidism following primary hypothyroidism due to Hashimoto's thyroiditis in a case of thyroid hemiagenesis: case report

Thyroid hemiagenesis (TH) is a rare inborn anomaly, resulting from failure of one thyroid lobe development. It is usually detected incidentally during investigation of concomitant thyroid disorders. The reported patient first presented hypothyroidism at the age of 49, when Hashimoto's thyroiditis (HT) and left thyroid lobe agenesis was diagnosed. L-thyroxine (LT4) replacement therapy restored hormonal balance. Two years later, the patient developed features of Graves' hyperthyroidism. The antithyroid pharmacotherapy by thiamazole was used. However, due to severe side-effects it was discontinued, and radioiodine treatment was applied. Four months after 131I administration, symptoms of hypothyroidism appeared, so thyroid hormone substitution was reintroduced. The patient, whose observation period has now reached 5 years, under LT4 replacement therapy, remains both clinically and biochemically euthyroid. The described case displays a very rare coincidence of hypothyroidism due to HT converted into Graves' hyperthyroidism, accompanying TH. Each of these three entities, may influence the thyroid function in a different way, hence, systematic follow-up and individual therapeutic management is required.     

Ectopic Acromegaly due to A Pancreatic Neuroendocrine Tumor Producing Growth Hormone-Releasing Hormone

ObjectiveTo present a case of acromegaly due to ectopic growth hormone-releasing hormone (GHRH) secretion from a pancreatic neuroendocrine tumor in the context of multiple endocrine neoplasia type 1 (MEN 1).MethodsWe describe the clinical, imaging, and pathologic findings of the study patient.ResultsA 46 year old woman presented with clinical and biochemical findings diagnostic of acromegaly. Magnetic resonance imaging showed a 1.2-cm sellar mass. Following resection of the macroadenoma, serum insulinlike growth factor 1 (IGF-1) and growth hormone (GH) levels remained unchanged. Pathologic examination revealed adenomatous changes, including a nonsecretory focus and a prolactin immunopositive area (GH stain negative in both). Octreotide long-acting release was ineffective. Search for an ectopic tumor included normal octreoscan and abdominal computed tomography. GHRH was greater than 1000 pg/mL. Repeated abdominal computed tomography documented a 6.2-cm mass in the tail and body of the pancreas. Distal pancreatectomy revealed a pancreatic neuroendocrine tumor that stained positive for GHRH. Postoperatively, serum GHRH and IGF-1 normalized. Re-evaluation of the initial pituitary pathologic specimen revealed additional somatotroph hyperplasia of the adjacent, normal pituitary gland. Primary hyperparathyroidism was diagnosed, and multigland parathyroid hyperplasia was noted at surgery. Genetic testing was positive for a mutation in the MEN1 gene.ConclusionThis patient’s acromegaly was resistant to somatostatin analogue therapy, reflecting the negative octreoscan imaging. In addition, this case is novel because the patient presented with pituitary adenomatous changes, which were presumably associated with MEN 1 and/or possibly the elevated GHRH levels. (Endocr Pract. 2011; 17:79-84)     

Accumulation of cytochrome P450 induced by proteasome inhibition during cardiac ischemia

Although differences in size of the right and left thyroid lobes are well defined, differences in morphology, follicles structure, cAMP production, thyrotropin receptor, and protein involved in cell signalling have not previously been reported. This study provides morpho-functional data of right and left thyroid lobes by biochemical, immunohistochemistry, immunoblotting and immunofluorescence analysis. We demonstrate that, in comparison with the left lobe, the right lobe has a higher activation index, is more sensitive to thyrotropin treatment, is rich in thyrotropin receptor and caveolin 1 involved in thyroid hormone synthesis as well as in epithelial thyroid cell homeostasis, is characterised by a high content of molecules involved in cell signalling such as stat3, raf1, sphingomyelinase and sphingomyelin-synthase whose activity ratio is necessary for epithelial cell activity and finally has more areas calcitonin-dependent. The relation between structure/function of right lobe and its susceptibility to the higher risk of pathological modifications with respect the left lobe is discussed.     

Thyroid cryotherapy in an experimental rat model-topography of temperature during therapy and functional results

The aim of this study was to investigate post cryotherapy thyroid function status of normal rat thyroid tissue and to determine the topography of temperature of cryotreated tissues and of tissues adjacent to them. Nitrous oxide cryotherapy was performed in 40 male Wistar rats. They were divided into four groups of 10. In group I, the right thyroid lobe was subjected to cryotherapy and the left lobe was not frozen. In group II, both thyroid lobes were cryotreated. In group III, the right lobe was frozen and the left lobe was excised. In group IV, the thyroid was subjected to neither cryotherapy nor surgery. During cryotherapy, the temperature in various places of the thyroid and in the surrounding tissues was measured. Serum thyrotropin concentrations were determined before an experiment and 4 weeks after in all rats. The results of temperature measurements proved that it is possible to limit cryotherapy to certain areas of thyroid tissue and to spare the neighboring tissues, because they are not subjected to temperatures that are damaging. The effectiveness of cryotherapy was confirmed by functional effect. Cryotherapy changed function of thyroid tissue. There was a statistically significant difference between mean baseline and follow-up concentrations in rats of groups II and III. In both groups hypothyroidism occurred post cryotherapy.     

A case of Cushing's syndrome associated with possible adrenomedullary hyperplasia

A 57-year-old male, who had been suffered from hypertension and diabetes mellitus for 10 years, was admitted to the hospital because of thirst, lassitude and muscle wasting. On admission, his urinary excretion of 17-OHCS and plasma cortisol levels were elevated without diurnal variations. Plasma ACTH levels were found to be very low with repeated determinations. Dexamethasone suppression test, 2 mg 4 times a day orally for 2 days, showed no changes in plasma cortisol levels and only a mild reduction in urinary 17-OHCS excretion. Estimation of urinary catecholamines showed an increase only in norepinephrine. Abdominal computerized tomography and radionuclide scanning of adrenal glands with 131I-adosterol demonstrated a well-defined adrenal mass in the left side without apparent changes in the right side. 131I-metaiodobenzylguanidine scintigraphy was negative. At surgery, his left adrenal medulla was found to be hypertrophic in addition to the cortical tumor. The left adrenal gland was also removed. After surgery, excretion of urinary catecholamines fell to nearly the normal range and he was discharged without insulin and antihypertensive drugs. Microscopically, the cortical tumor is an adenoma consisting of lipid laden cells and eosinophilic compact cells. Medullary cells were distinctly hyperplastic in appearance and many of the cells were extensively vacuolated, suggesting an active functional status. The present report describes a patient with Cushing's syndrome who showed increased urinary catecholamine excretion due to the possible coexistence of adrenal medullary hyperplasia. As far as we know, this is the first case of Cushing's syndrome with this abnormality.     

Multiglandular Parathyroid Carcinoma: Case Report and Review of The Literature

ObjectiveTo report the fifth case of multiglandular parathyroid carcinoma and highlight the necessity of bilateral neck exploration in some circumstances.MethodsWe report a case of simultaneous bilateral and multiglandular parathyroid carcinoma in a 48-yearold woman presenting with primary hyperparathyroidism. Ultrasonography revealed a 24-by 24-by 34-mm nodule on the right lobe of the thyroid and a 20-by 20-by 32-mm parathyroid gland inferior to the left thyroid lobe. Technetium Tc 99m sestamibi scan revealed bilateral increased uptake consistent with the parathyroid glands. She was treated with bilateral neck exploration and parathyroidectomy with en bloc resection of the adjacent thyroid lobe in the right lower gland and parathyroidectomy with resection of surrounding soft tissue in the left lower gland.ResultsThe presence of a thick fibrous capsule, invasion of surrounding tissues, trabecular and solid growth pattern without necrotic foci, and vascular invasion on pathology slides enabled the diagnosis of parathyroid carcinoma of both glands. Her calcium and parathyroid hormone levels were within normal limits during a follow-up period of 4 years.ConclusionSince surgical resection offers the only curative treatment and initial operation may be the determinant of survival, a high index of suspicion for carcinoma both clinically and intraoperatively is vital. We aim to reemphasize that bilateral neck exploration in select cases of parathyroid carcinoma should be considered if there is concrete evidence of a second tumor, since parathyroid carcinoma can coexist with hyperplasia, adenoma, or even carcinoma of other parathyroid glands. (Endocr Pract. 2011;17:e79-e83)     

Pituitary metastasis of follicular thyroid carcinoma

OBJECTIVE: The case of a 60-year-old male patient with follicular thyroid cancer who developed a pituitary mass proved to be a metastasis from thyroid cancer. METHODS: Assessment with whole-body scan, ultrasound, computed tomography and thyroglobulin measurements. RESULTS: Despite surgery and repeated doses of radioiodine, the patient developed diplopia and ptosis of the right eyelid, along with increasing thyroglobulin levels. A pituitary mass was discovered, with no signs of pituitary deficiency. The mass was removed and found to consist of neoplastic cells immunohistochemically positive to thyroglobulin. CONCLUSIONS: Distant metastases may develop in cases of follicular thyroid carcinoma, even after repeated doses of (131)I. Metastatic follicular thyroid carcinoma to the pituitary is a rare entity.     

C cells in normal thyroid aspirates.

OBJECTIVE: To quantify C cells in normal thyroid aspirates. STUDY DESIGN: Smears of 18 glands from patients with no thyroid disease, 8 women and 10 men aged on average 52.8 years, were analyzed. Five samples were aspirated from the upper, middle and lower thirds of each lateral lobe and from the isthmus. Smears were stained with anticalcitonin monoclonal antibody. RESULTS: C cells were detected in all specimens, ranging in number from 3 to 19 per gland, with 53.4% of the cells in the right lobe, 42.8% in the left lobe and 3.7% in the isthmus. The aspirates from the right lobe had 0-13 cells in the upper third, 0-9 in the middle third and 0-3 in the lower third. In the left lobe aspirates there were 0-7 cells in the upper third, 0-6 in the middle third and 0-2 in the lower third. One to two C cells were observed in the isthmus in only four cases. CONCLUSION: It is possible to determine the presence of C cells in normal thyroids and confirm studies conducted on histologic material; the cells were more frequently detected in the middle and upper third and mainly on the right side. They were rare in the isthmus. The search for C cells in thyroid aspirates is of great importance because it permits one to confirm rapidly, precisely and minimally invasively cases suspected of C cell hyperplasia, a preneoplastic condition that precedes the development of medullary carcinoma. In addition, the method shows numerical changes in these cells in such conditions as Hashimoto's thyroiditis and colloid goiter, in which the present results could serve as a control.     

Ectopic Intrathyroidal Nonfunctioning Parathyroid Cyst

ObjectiveTo describe a rare case of ectopic intrathyroidal parathyroid cyst (PC) in a 29-year-old woman who had been referred to us because of a multinodular goiter.MethodsWe review the clinical, laboratory, and radiographic findings as well as the treatment in our patient and provide a brief discussion of the associated literature.ResultsUltrasonography of the neck showed the presence of 2 thyroid nodules in the left lobe, the larger of which was solid and the smaller of which had a cystic appearance. A small nodular area was also found in the right thyroid lobe (diameter, less than 8 mm). A thyroid scan performed with technetium showed the absence of uptake by both left lobe nodules. Fine-needle aspiration biopsy (FNAB) of the 2 major nodular lesions revealed that the larger thyroid nodule was benign and the smaller was a cyst with clear fluid. Measurement of parathyroid hormone in the FNAB fluid showed a high concentration, suggestive of the diagnosis of PC. Normal serum levels of parathyroid hormone and calcium indicated that it was a nonfunctioning intrathyroidal PC. The PC disappeared after FNAB, but the lesion recurred 3 months later. Therefore, the patient underwent near-total thyroidectomy. Histologic examination confirmed the diagnosis of intrathyroidal PC, and a papillary microcarcinoma (6 mm in diameter) was found in the right lobe of the thyroid.ConclusionAlthough an ectopic intrathyroidal PC is rare, the frequency of occult papillary microcarcinoma of the thyroid is high. The association we describe, however, should be considered incidental. To our knowledge, this is the first report of an association of an intrathyroidal PC with papillary microcarcinoma of the thyroid. (Endocr Pract. 2007;13:56-58)     

Mammary radioiodine accumulation due to functional sodium iodide symporter expression in a benign fibroadenoma

The sodium iodide symporter (NIS) has been characterized to mediate the active transport of iodide not only in the thyroid gland but also in various non-thyroidal tissues, including lactating mammary gland and the majority of breast cancers, thereby offering the possibility of diagnostic and therapeutic radioiodine application in breast cancer. In this report, we present a 57-year-old patient with multifocal papillary thyroid carcinoma, who showed focal radioiodine accumulation in a lesion in the right breast on a posttherapy (131)I scan following radioiodine therapy. CT and MR-mammography showed a focal solid lesion in the right breast suggestive of a fibroadenoma, which was confirmed by histological examination. Immunostaining of paraffin-embedded tumor tissue sections using a human NIS antibody demonstrated NIS-specific immunoreactivity confined to epithelial cells of mammary ducts. In conclusion, in a thyroid cancer patient we identified a benign fibroadenoma of the breast expressing high levels of functionally active NIS protein as underlying cause of focal mammary radioiodine accumulation on a posttherapy (131)I scan. These data show for the first time that functional NIS expression is not restricted to lactating mammary gland and malignant breast tissue, but can also be detected in benign breast lesions, such as fibroadenomata of the breast.     

Carcinoembronic antigen and endocrine response in a patient with Sipple's syndrome following surgery

Circulating carcinoembryonic antigen (CEA), calcitonin (CT) and adrenocorticotropic hormone (ACTH) and levels in tissue extracts of a patients with Sipple's syndrome were measured simultaneously. Biofocal medullary carcinoma of the thyroid gland (MCT), left adrenal phaeochromocytoma and ectopic para-aortal phaeochromocytoma had been removed in the first operation. Total thyroidectomy was performed thereafter. Evidence has been presented showing that (1) the first operation lowered the elevated serum levels of CEA and CT, and levels of CEA and CT in tissue extracts of MCT were considerably higher than those of tumor-uninvolved thyroid tissue and phaeochromocytomas; (2) markedly elevated levels of plasma ACTH were normalized by the first surgery and, in addition, immunoreactive ACTH and beta-melanocyte stimulating hormone (beta-MSH) were detected in the phaeochromocytomas removed. This is a documented case of the simultaneous production of CT and CEA by MCT associated with ectopic secretion of ACTH and beta-MSH from the phaeochromocytomas without manifesting clinical features of Cushing's syndrome and is based on the findings referred to above.