Unusual Case of Metastatic Neuroendocrine Tumor

ObjectiveTo report a rare case of metastatic growth hormone (GH)-secreting pituitary carcinoma causing acromegaly.MethodsWe present a case report and review the available literature on this topic.ResultsA 68-year-old woman presented with persistent acromegaly after treatment for a GH-secreting pituitary adenoma. Evaluation of long-standing cervical adenopathy revealed findings consistent with a metastatic neuroendocrine tumor. Further work-up revealed additional thyroid, parathyroid, and cervical masses. After operative treatment including total thyroidectomy, subtotal parathyroidectomy, partial thymectomy, and right modified radical neck dissection, the patient’s symptoms diminished, and her GH levels approached the normal range. Surgical pathology findings were consistent with a GH-secreting pituitary carcinoma metastatic to the cervical lymph nodes, multinodular thyroid hyperplasia with a focus of papillary microcarcinoma, and parathyroid hyperplasia.ConclusionOverall, pituitary carcinomas are extremely rare. To date, about 100 cases have been reported in the world’s literature, and of these, only 19 cases originated from GH-secreting cells. Our examination of the symptoms, signs, diagnosis, and treatment of our patient, in comparison with the previously reported cases, should enhance awareness of this unusual disease process. (Endocr Pract. 2007;13:72-76)     

Metastatic Renal Cell Carcinoma to the Thyroid Gland

ObjectiveTo examine the presentation, diagnosis, and appropriate management of renal clear cell carcinoma metastasis to the thyroid gland.MethodsWe describe a clinical case of solitary thyroid metastasis from renal clear cell carcinoma and present a comprehensive review of the related English-language literature. Common patterns of presentation and generalized overall management recommendations are evaluated and summarized.ResultsEight years after nephrectomy for renal carcinoma at age 61 years, a man presented with a thyroid mass. Cytology and histopathologic surgical findings were consistent with a solitary metastasis most compatible with metastatic clear cell carcinoma from his previous renal carcinoma. After left thyroid lobectomy and isthmusectomy, the patient remains disease-free 5 years later. Although uncommon, nearly 150 cases of clinically recognized metastatic renal cell carcinoma to the thyroid have been reported in the English-language literature. Metastatic disease from the kidney to the thyroid gland can occur more than 20 years after nephrectomy with the average time interval being 7.5 years. Obtaining a full clinical history in any patient who presents with a thyroid nodule is essential to allow consideration of possible metastatic disease from previous primary tumor. Metastatic disease to the thyroid gland can be correctly diagnosed preoperatively. If metastatic renal cancer is limited to the thyroid gland only, prompt, appropriate surgical intervention can be curative.ConclusionMetastatic renal carcinoma to the thyroid should be considered in any patient presenting with a thyroid mass and a medical history of renal cell carcinoma. (Endocr Pract. 2008;14:1040-1046)     

Genetics,Diagnosis, and Management of Medullary Thyroid Carcinoma and Pheochromocytoma/Paraganglioma

ObjectiveMedullary thyroid carcinoma (MTC) and pheochromocytoma/paraganglioma (PHEO/PGL) are rare neuroendocrine tumors. Because of the increased metastatic rates in certain genetic backgrounds, early diagnosis and treatment are essential to improved patient outcomes. Our objective was to summarize recent findings related to the genetics, diagnosis, and management of MTC and PHEO/PGL.MethodsA literature review was performed.ResultsMTC is primarily associated with mutations in the rearranged during transfection (RET) protooncogene. Determining the specific genetic mutation can guide patient management and screening. Early detection and appropriate surgical management of MTC is critical to prevent or limit metastatic spread, as treatment options for patients with metastatic disease are limited. PHEO/PGL also has a strong genetic component, with approximately 50% of cases linked to germline and somatic mutations in 15 genes. Although most PHEO/PGLs are benign, factors such as genetic background, size, tumor location, and high methoxytyramine levels are associated with higher rates of metastatic disease. The state-of-the-art diagnosis and localization of PHEO/PGLs is based on measurement of plasma metanephrines and methoxytyramine and functional imaging studies. For both PHEO/PGL and MTC, surgery is the only curative treatment. Treatment options for patients with metastatic disease are limited.ConclusionAs genetic testing becomes more widely available, the diagnosis of MTC and PHEO/PGL will be made earlier due to routine screening of at-risk patients. In addition, continued advances in basic science, diagnostic methods, and imaging techniques will improve understanding of the pathogenesis of these diseases and facilitate the introduction of novel treatment strategies for patients with metastatic disease. (Endocr Pract. 2014;20:176-187)     

Delayed treatment of papillary thyroid carcinoma arising from struma ovarii in a patient with history of bilateral salpingo-oophorectomy: a case report

ObjectiveWe present a case of papillary thyroid carcinoma arising from struma ovarii treated erroneously as ovarian adenocarcinoma for more than 3 years.MethodsWe report clinical, surgical, laboratory, and imaging findings of the study patient and review the relevant literature.ResultsA 64-year-old woman was treated for ovarian adenocarcinoma for more than 3 years before it was determined that she likely had papillary thyroid carcinoma arising from struma ovarii. This is the first reported case of thyroid carcinoma arising from struma ovarii in a patient with a history of bilateral salpingo-oophorectomy. Possible etiologies include residual ovarian tissue after oophorectomy, ectopic thyroid, or metastatic thyroid cancer.ConclusionsIt is important to include struma ovarii and thyroid carcinoma arising from struma ovarii in the differential diagnosis, even with a history of bilateral salpingo-oophorectomy. This case emphasizes the importance of effective communication among the pathologist, oncologist, and surgeon to ensure timely initiation of appropriate therapy and reduced patient morbidity. (Endocr Pract. 2012;18:e1-e4)     

Medullary Thyroid Cancer that Stains Negative for CA 19-9 has Decreased Metastatic Potential

Objective: Presently, no clinical tools are available to diagnose the metastatic potential of medullary thyroid cancer (MTC) at disease presentation. Surveillance with calcitonin (Ct) and carcinoembryonic antigen (CEA) is currently recommended for the observation and diagnosis of metastatic disease after initial treatment of MTC. Recently, carbohydrate antigen (CA)19-9 staining has been associated with aggressive forms of MTC and metastatic spread. This pilot study explored whether positive CA19-9 staining of MTC tissue is associated with its metastatic potential.Methods: Sixteen cases of MTC were identified, and tissue specimens were immunostained for CA 19-9 and other MTC tumor markers. Clinical information about patients' MTC was collected through a retrospective chart review.Results: Overall, 63% of the specimens stained positive for CA19-9. The median size of positively staining specimens was 2.6 cm (interquartile range [IQR] 1.2-3.2) compared to 0.7 cm (0.5-1.2) in negatively staining MTC specimens (P = .04). All specimens from patients diagnosed with stage IV MTC stained positive for CA19-9, compared to only 40% of cases that were classified as stages I to III (P = .03). Furthermore, 100% of the primary specimens that were documented to have metastatic spread stained positive for CA19-9. The sensitivity for ruling out stage IV MTC based on negative staining for CA 19-9 was 100%.Conclusion: Based on these results, we conclude that negative staining of MTC for CA19-9 may be associated with its decreased metastatic potential.Abbreviations: CA = carbohydrate antigen CEA = carcinoembryonic antigen Ct = calcitonin IHC =immunohistochemistry MTC = medullary thyroid cancer     

Medullary Thyroid Carcinoma

ObjectiveThis review outlines advances in the diagnosis, genetic testing, and progress in medullary thyroid cancer (MTC) treatment in light of the most recent evidence.MethodsEnglish-language articles pertaining to MTC published up to 2012 were reviewed. The pertinent articles and their references were obtained and those considered relevant were reviewed for inclusion.ResultsMTC is an uncommon neuroendocrine malignancy that accounts for 5% of thyroid cancers. MTC presents in sporadic and familial forms (multiple endocrine neoplasia [MEN] 2A, MEN 2B, or familial MTC syndromes). The familial forms are secondary to germline mutations in the REarranged during Transfection (RET) proto-oncogene. Early diagnosis and treatment is paramount. Genetic testing has made possible early detection in asymptomatic carriers and high-risk patients, with early or prophylactic surgery being curative in many. All carriers of an RET mutation should be evaluated and treated surgically for MTC. The primary treatment in all patients diagnosed with MTC is total thyroidectomy with central lymph node dissection. Calcitonin and carcinoembryonic antigen levels can be used as prognostic factors and as tumor markers. If elevated, further investigation, including use of imaging modalities, may be necessary for evaluation of metastatic disease. Surgery remains the main treatment for local and locally advanced disease.ConclusionMTC is rare, but morbidity and mortality remain high if untreated. Genetic testing should be offered to all patients. Treatment of choice remains total thyroid-ectomy and central lymph node dissection. Palliative treatment for advanced disease includes surgery, radiation, standard chemotherapy, chemoembolization and more recently, targeted therapies (tyrosine kinase inhibitors). (Endocr Pract. 2013;19:703-711)     

Unusual Manifestation of Parathyroid Carcinoma in the Setting of Papillary Thyroid Cancer

ObjectiveTo describe a rare manifestation of parathyroid carcinoma in association with papillary thyroid carcinoma.MethodsWe describe the clinical history, findings on physical examination, results of laboratory studies, imaging findings, and histopathologic features of a woman with 2 previously palpable thyroid nodules and mild hypercalcemia.ResultsA 79-year-old woman presented to our endocrinology clinic for reevaluation of 2 thyroid nodules and long-standing hyperparathyroidism. She initially had undergone assessment 6 years previously, at which time an intact parathyroid hormone level was 89 pg/mL (reference range, 10 to 69) and the serum calcium concentration was 10.4 mg/dL (reference range, 8.2 to 10.2) in conjunction with normal alkaline phosphatase, creatinine, and 25-hydroxyvitamin D levels. Subsequently, she was found to have multifocal papillary thyroid cancer in the right thyroid lobe and a 5-cm parathyroid carcinoma in the left side.ConclusionSynchronous parathyroid and thyroid carcinomas are extremely rare. To our knowledge, our current case is the first documented patient with parathyroid carcinoma who had a clinical presentation consistent with longstanding mild adenoma in addition to synchronous papillary thyroid carcinoma. (Endocr Pract. 2010;16:664-668)     

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)     

The Diagnostic Value of Calcitonin Measurement in Wash-out Fluid from Fine-Needle Aspiration of Thyroid Nodules in the Diagnosis of Medullary Thyroid Cancer

ObjectiveThe diagnostic value of calcitonin measurement in fine-needle aspiration biopsy (FNAB) washout fluid (Ct-FNAB) for medullary thyroid cancer (MTC) remains to be determined. This prospective study aimed to assess the diagnostic value of Ct-FNAB in thyroid nodules in comparison with basal serum calcitonin (Ct), pentagas- trin-stimulated Ct (Pg-sCt), and cytology.MethodsAmong patients with goiter addressed with US-FNAB who had an initial clinical suggestion for thyroidectomy, 27 patients with thyroid nodule/s (n = 60) and normal, borderline, or increased Ct fulfilled the criteria for thyroidectomy. All 27 patients (enrolled according to exclusion/inclusion criteria) underwent ultrasonography (US), Ct, Pg-sCt, US-assisted FNAB of each patient’s nodule for both cytology, and Ct-FNAB before thyroidectomy.ResultsCt-FNAB always resulted in >1,000 pg/mL in MTC nodules at histology. For values between 36 and pg/mL, MTCs and nodular or micronodular C-cell hyperplasia (CCH) results overlapped. Most of the nodules without MTC and/or CCH had Ct-FNAB <17 pg/mL. Ct-FNAB diagnostic power was superior to and similar to other diagnostic procedures (Ct, Pg-sCt, and cytology) in identifying both MTC and CCH, and MTC alone, respectively.ConclusionThe diagnostic power of Ct-FNAB is valuable compared with other routine procedures. Ct-FNAB is highly reliable for the early detection and accurate localization of MTC in thyroid nodules, but it does not differentiate between MTC and CCH. Ct-FNAB is an extremely valuable diagnostic tool, especially considering that other diagnostic procedures do not provide a definitive diagnosis, and it can be included in the clinical work-up of thyroid nodules when MTC is suspected. (Endocr Pract. 2013;19:769-779)     

Calcitonin-Secreting Pancreatic Neuroendocrine Tumors: A Case Report and Review of the Literature

ObjectiveWe report the presentation and novel therapy of a calcitonin-secreting pancreatic neuroendocrine tumor (PNET) and review the literature on this unusual neoplasm.Methods:We cite the history of a 38-year-old male who presented with fatigue, weight loss, and diarrhea and was found to have a pancreatic head mass on cross-sectional imaging, as well as liver metastases.Results:The patient’s laboratory evaluation was notable for a >100-fold elevation of the peptide hormone calcitonin in serum. As calcitonin is typically secreted by thyroid C-cells, hypercalcitoninemia is considered a marker for medullary thyroid cancer (MTC) or C-cell hyperplasia, but it may be present in several physiologic or pathologic conditions or may be ectopically secreted in rare PNETs. An octreotide scan confirmed the presence of somatostatin (SST) receptors on the pancreatic mass and liver metastases, leading to the diagnosis of a calcitonin-secreting PNET. We initiated treatment with long-acting SST analogs and peptide receptor radionuclide therapy (⁹⁰Yttrium-DOTATOC) and achieved disease regression while maintaining a high quality of life.Conclusion:Functional PNETs that secrete calcitonin are exceedingly rare, but they are important to consider in the differential diagnosis of nonthyroid-mediated hypercalcitonemia or pancreatic tumors that present with diarrhea, as the management differs markedly from both MTC and other pancreatic malignancies. (Endocr Pract. 2014;20:e140-e144)     

Mixed Corticomedullary Carcinoma of the Adrenal Gland: A Case Report

ObjectiveTo report the case of a 78-year-old woman with mixed corticomedullary carcinoma of the adrenal gland, and to review other reported lesions that exhibit clinical and/or histopathologic features of both adrenal cortical and medullary differentiation.MethodsWe describe the patient’s clinical findings and laboratory test results, as well as the gross and histopathologic features of her tumor. We also review the literature pertaining to mixed corticomedullary adenomas and cortical tumors with clinical features of pheochromocytoma, and vice versa.ResultsA 78-year-old woman with a 10-cm left adrenal mass was hospitalized for management of hypertensiveurgency. Laboratory workup revealed elevated urinary metanephrine excretion and elevated serum dehydroepiandrosterone sulfate levels. She underwent left adrenalectomy. Pathologic examination of the lesion showed mixed cortical and medullary histologic characteristics, as well as gross and microscopic evidence of malignancy. Including the present case, we identified 17 cases of neoplasms that exhibit features of mixed corticomedullary differentiation.ConclusionsThis report represents the first documented case of mixed corticomedullary carcinoma. Several benign lesions combine clinical, biochemical, and/or histopathologic evidence of both adrenal cortical and medullary differentiation, including mixed corticomedullary adenomas and corticotropin-secreting pheochromocytomas. The differential diagnosis of a lesion with mixed cortical and medullary features should also include a malignant neoplasm. (Endocr Pract. 2012;18:e37-e42)     

Interferon-Induced Hypothyroidism Causing Reversible Pituitary Enlargement

ObjectiveTo present the first reported case of interferon-induced hypothyroidism with radiographic confirmation of secondary pituitary hyperplasia.MethodsWe describe the case of a woman with recurrent malignant melanoma, outline the details of her endocrine work-up, and illustrate the serial findings on magnetic resonance imaging of the head.ResultsA 26-year-old woman underwent surgical excision of a melanoma of the left thigh and 10 years later had a second melanoma removed from her right knee. Metastatic work-up revealed evidence of tumor involvement in the cervical and mediastinal lymph nodes. After treatment with interferon for 1 year, persistent fatigue and menstrual irregularities led to the laboratory diagnosis of hypothyroidism, and magnetic resonance imaging revealed pituitary enlargement. Both her endocrinopathy and the pituitary hyperplasia resolved with discontinuation of the interferon treatment and with institution of thyroid replacement therapy.ConclusionClinicians should be aware of the potential adverse effects of interferon therapy to avoid inappropriate diagnosis of a pituitary adenoma or metastatic lesion in patients with cancer who are treated with interferon. In addition, screening for hypothyroidism should be performed in patients receiving interferon. (Endocr Pract. 2008;14:219-223)     

Incidental Finding of Metastatic Papillary Thyroid Carcinoma in a Patient with Primary Hyperparathyroidism

ObjectiveTo report on the management of a patient with the rare concurrence of primary hyperparathyroidism and incidentally found metastatic papillary thyroid carcinoma in an adjacent lymph node.MethodsWe present a case report, including scintigraphic and histologic documentation, and a summary of the related literature.ResultsPrimary hyperparathyroidism with concomitant occurrence of nonmedullary thyroid carcinoma is rare, occurring in less than 4% of patients. We report a case of a 53-year-old woman with no prior history of endocrine disease with primary hyperparathyroidism and an incidental finding of a concurrent thyroid carcinoma. In this patient, technetium 99m scintigraphy revealed a parathyroid adenoma beneath the inferior pole of the left thyroid bed. Parathyroidectomy was performed successfully with no complications. The final pathology examination showed a large parathyroid adenoma with an incidental finding of a small adjacent lymph node containing metastatic papillary thyroid carcinoma. The patient subsequently underwent total thyroidectomy, and the pathology evaluation revealed papillary thyroid carcinoma, follicular variant.ConclusionTo our knowledge, this case of concomitant primary hyperparathyroidism and papillary thyroid cancer is unique in the way in which the diagnosis of metastatic papillary thyroid cancer was made. The presence of parathyroid adenoma should not exclude the diagnosis of thyroid carcinoma; therefore, careful thyroid evaluation should be considered for all patients with primary hyperparathyroidism. (Endocr Pract. 2007;13:380-383)     

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)     

Papillary Carcinoma of the Thyroid with Fibromatosislike Stroma: Case Report and Review of Literature

ObjectiveTo describe a case of papillary carcinoma of the thyroid with fibromatosislike stroma, emphasize the need for a diligent search for papillary thyroid cancer in the presence of a fibroproliferative lesion, highlight the peculiar hormonal response of the stromal component, and review the pertinent literature.MethodsWe present the clinical, laboratory, radiologic, and pathologic findings in a patient with papillary carcinoma of the thyroid with fibromatosislike stroma and review the related published material.ResultsA 29-year-old woman presented to our surgical department because of a large mediastinal mass. She underwent surgical removal of the mass by means of a median sternotomy and neck extension. Pathology examination revealed macroscopically tan scarlike tissue, which by histologic study consisted of a dominant fibroproliferative lesion overshadowing a minor component of papillary carcinoma of the thyroid. Further neck exploration with total thyroidectomy revealed multifocal papillary carcinoma of the thyroid. Postoperatively, the patient received radioiodine treatment. A local and aggressive recurrent tumor was observed during a subsequent pregnancy; the lesion was not amenable to complete resection but fascinatingly responded to antiestrogen therapy (orally administered tamoxifen).ConclusionThe presence of a fibroproliferative lesion could be misleading. A diligent search should be made for a papillary thyroid carcinoma component within fibromatosislike stroma. The mode of manifestation of the tumor and its response to hormonal manipulation are distinctive features of this case. (Endocr Pract. 2010;16:650-655)     

CALCITONIN SECRETORY INDEX AND UNSUSPECTED NODAL DISEASE IN MEDULLARY THYROID CARCINOMA

Objective: Medullary thyroid carcinoma (MTC) is a rare thyroid malignancy originating from parafollicular C-cells with the potential for aggressive behavior. The extent of lymph node (LN) dissection at the time of surgery is controversial, with different schools of thought prevailing. Some systematically perform LN dissections, whereas others base their decision on radiologic evidence of disease and some with the assistance of pre-operative calcitonin (CT) levels.Methods: We retrospectively assessed the correlation between pre-operative CT levels and clinico-pathologic factors among 42 patients with MTC between 1994 and 2015. Furthermore, we refined the use of pre-operative serum CT levels and explored for the first time a test called the Calcitonin Secretory Index (CSI, ng/mL/mm).Results: Pre-operative CT levels correlated independently with tumor size (P<.0001), number of metastatic LNs (P<.01), and increased rates of distant metastasis. The CSI better predicted early LN disease (P<.045). Patients with early LN metastasis had a CSI >30 ng/mL/mm, a representative threshold above which the surgical cure declines considerably.Conclusion: In our experience, pre-operative CT levels and now the CSI appear as sensitive and specific risk stratification markers for MTC. Despite negative findings on dedicated pre-operative neck imaging in addition to total thyroidectomy, a CSI >30 ng/mL/mm would prompt bilateral central node dissection. Due to the small sample size, our study provides preliminary evidence of the value of CSI in clinical practice.Abbreviations: ANOVA = analysis of variance; ATA = American Thyroid Association; CSI = Calcitonin Secretory Index; CT = calcitonin; LN = lymph node; MTC = medullary thyroid carcinoma; ROC = receiver operating characteristic     

Papillary Carcinoma of a Thyroglossal Duct Cyst in a Patient with Thyroid Hemiagenesis: Effectiveness of Conservative Surgical Treatment

ObjectiveTo describe a case of thyroglossal duct cyst carcinoma that arose in a patient with right thyroid lobe hemiagenesis.MethodsWe present the imaging, physical examination findings, treatment, and clinical course of the study patient.ResultsA 35-year-old woman was evaluated for a neck mass that had been present for 6 months and was slowly growing. She reported a previous diagnosis of right hemithyroid agenesis. The patient’s preoperative workup included ultrasonography of the neck and head and neck T1- and T2-weighted magnetic resonance imaging, which showed right hemithyroid agenesis and a cystic lesion in the median region of the neck below the hyoid bone. Findings from chest x-rays and thyroid function tests were normal. The patient underwent a modified Sistrunk procedure that included removal of the median portion of the hyoid bone. Histologic findings showed a 2.5-cm thyroglossal duct cyst with a 0.6-cm focus of follicular variant of papillary carcinoma with invasion of the cyst wall. Total thyroidectomy was not performed because of the absence of tumoral invasion of the parenchyma around the thyroglossal duct cyst and because the patient was at low risk for aggressive disease. Cervical ultrasonography examinations were performed 6, 12, and 24 months after treatment, and all findings were normal. Presently, the patient is symptom-free after 4 years of follow-up and has no evidence of disease.ConclusionIncidentally discovered, well-differentiated thyroid cancer that is confined to a thyroglossal duct cyst in a patient at low risk for aggressive disease can be adequately treated by a modified Sistrunk procedure that includes the median portion of the hyoid bone. (Endocr Pract. 2008;14:465-469)     

A Case of Riedel’s Thyroiditis Treated with Tamoxifen: Another Successful Outcome

ObjectiveTo report a case of Riedel’s thyroiditis, which was successfully treated with tamoxifen.MethodsWe present the clinical, laboratory, and imaging findings and describe the clinical course of a patient with Riedel’s thyroiditis.ResultsA 40-year-old woman presented with hypothyroidism and a large goiter, which was unresponsive to hormone replacement therapy. Magnetic resonance imaging confirmed the presence of an enlarged thyroid gland, more pronounced on the right than on the left. The patient had progressive discomfort attributable to compressive symptoms in the neck. Surgical exploration of the neck disclosed a hard, immobile thyroid mass, which could not be resected because of adherence to surrounding structures. Biopsy of the thyroid and of the muscles of the neck revealed Riedel’s thyroiditis. Treatment with tamoxifen, in a dosage of 20 mg twice a day for more than 1½ years, completely resolved the neck mass (substantiated by follow-up magnetic resonance imaging) and relieved the signs and symptoms of compression of the neck.ConclusionTamoxifen treatment is effective in resolving the mass and compression in Riedel’s thyroiditis. (Endocr Pract. 2004;10:483-486)