Clinical and pathological characteristics of secondary thyroid cancer

To diagnose primary and secondary squamous cell carcinoma of the thyroid with ultrasound malignancy risk stratification

Objectives

This study aimed to investigate the clinico-ultrasound features of primary squamous cell carcinoma of the thyroid (PSCCT) and secondary SCCT (SSCCT) and evaluate the accuracy of fine needle aspiration (FNA) recommendation for SCCT with American College of Radiology-Thyroid Imaging and Reporting Data System (ACR-TIRADS) and Chinese-TIRADS (C-TIRADS).

Materials and methods

We retrieved 26 SCCT patients (11 PSCCT, 15 SSCCT) from our hospital's pathology database (5,718 patients with thyroid malignancy) over 23 years. Medical records and ultrasound data of the 26 patients with 27 SCCTs were analyzed retrospectively, and each SCCT focus was categorized based on the two TIRADSs.

Results

For 26 patients (21 males, 5 females) with an age range of 42-81 years, rapidly enlarging thyroid/neck nodules (18/26, 69.2%), dysphagia (7/26, 26.9%), hoarseness (6/26, 23.1%), dyspnea (5/26, 19.6%), cough (4/26, 15.4%), neck pain (2/26, 7.7%), B symptoms (2/26, 7.7%), and blood in sputum (1/26, 3.8%) were presented at diagnosis. Five asymptomatic patients (5/26, 19.2%) were detected by ultrasound. Hoarseness was more common in PSCCT (5/11, 45.5%) than in SSCCT (1/15, 6.7%) (P=0.032). For 27 SCCTs with a mean size of 3.7 ± 1.3 cm, the ultrasound features consisted of solid (25/27, 92.6%) or almost completely solid composition (2/27, 7.4%), hypoechoic (17/27, 63%) and very hypoechoic echogenicity (10/27, 37%), irregular/lobulated margin with extra-thyroidal extension (27/27, 100%), taller-than-wide shape (13/27, 48.1%), punctate echogenic foci (6/27, 22.2%), hypervascularity (23/27, 85.2%) and involved neck lymph (13/26, 50.0%). A total of 27 SCCTs were evaluated as high malignancy risk stratification (≥TR4 and 4B) by the two TIRADSs and recommended FNA in 96.3-100% (26/27, 27/27). Pathologically, more than half of PSCCTs (7/12, 58.3%) and a quarter of SSCCTs (4/15, 26.7%) were poorly differentiated, while moderately and well-differentiated grades were observed in 5 PSCCTs and 11 SSCCTs (P=0.007). Thirteen patients (50.0%) underwent surgery with radical operation in 5 cases (5/13, 38.5%).

Conclusion

SCCT is an extremely rare and aggressive malignancy with a male predominance. PSCCT and SSCCT had similar clinical and ultrasound features except for tumor differentiation and the symptom of hoarseness. SCCT showed a high malignancy risk stratification in ACR-TIRADS and C-TIRADS, with a high rate of FNA recommendation.

Locally sourced: site-specific immune barriers to metastasis

Tumour cells migrate very early from primary sites to distant sites, and yet metastases often take years to manifest themselves clinically or never even surface within a patient's lifetime. This pause in cancer progression emphasizes the existence of barriers that constrain the growth of disseminated tumour cells (DTCs) at distant sites. Although the nature of these barriers to metastasis might include DTC-intrinsic traits, recent studies have established that the local microenvironment also controls the formation of metastases. In this Perspective, I discuss how site-specific differences of the immune system might be a major selective growth restraint on DTCs, and argue that harnessing tissue immunity will be essential for the next stage in immunotherapy development that reliably prevents the establishment of metastases.

Thyroid Metastasis from Primary Breast Cancer

Breast cancer (BC), the most commonly diagnosed malignancy, frequently metastasizes to the bone, lungs, brain and liver at advanced stages, whereas the thyroid gland represents a rare target site for secondary disease. We examined the most recent literature about thyroid metastasis (TM) from BC after we encountered a peculiar case of a 71-year-old woman who developed sudden dysphagia, severe hypothyroidism and hypoparathyroidism due to TM 18 years after the diagnosis of her primary cancer. Based on published data, the prevalence of TM in BC ranges from 3% to 34%, with a median onset time of 48.2 months, although longer time intervals are not infrequent. TM negatively impacts the prognosis of these patients, however thyroid surgery can limit the local disease burden. Therefore, we suggest that clinicians involved in the follow-up care of BC patients should consider a differential diagnosis of secondary thyroid malignancy when incidental lesions are diagnosed during radiological evaluations or local symptoms affect the cervical region, even many years after the diagnosis of the primary cancer.

177 Lu-DOTATATE PRRT for Multiple Unusual Metastatic Sites in Neuroendocrine Tumor

ABSTRACT

Thyroid gland and orbit are rare sites of metastases in neuroendocrine tumors. We present an extremely rare case of rectal neuroendocrine tumor with metastases to thyroid gland and intra-orbital regions that demonstrated significant reduction in size and uptake of the lesions on somatostatin receptor based 68 Ga-DOTATATE PET/CT, following 177 Lu-DOTATATE peptide receptor radionuclide therapy. The case illustrates the efficacy of 177 Lu-DOTATATE peptide receptor radionuclide therapy for tumor cytoreduction, which can be considered as a promising treatment modality for somatostatin receptor expressing and tracer-avid metastatic lesions at multiple rare locations.

Metastasis of liver cancer to the thyroid after surgery: A case report

BACKGROUND

Secondary thyroid malignancies are rarely reported, especially thyroid metastasis after resection of hepatocellular carcinoma (HCC). We report a patient with thyroid metastasis after resection of HCC.

CASE SUMMARY

A 42-year-old female underwent partial hepatectomy for HCC three years ago. She attended hospital because of neck discomfort. After various examinations, she was diagnosed with metastatic HCC. She survived after surgical resection of the affected side of the thyroid.

CONCLUSION

Although secondary malignant tumor of the thyroid is classified as distant metastasis, surgical resection is still necessary according to the patient's condition.

Thyroid Metastasis in Whole-Body 18F-FDG PET/CT Restaging of Small Cell Lung Cancer

ABSTRACT

Incidental findings of thyroid lesions, some of which show increased FDG uptake, are common in whole-body FDG PET/CT imaging of oncological patients. As metastases to the thyroid are extremely rare, it is often a matter of debate, whether thyroid lesions should be considered as benign goiter or evaluated further. Here, we present the case of a 65-year-old woman with history of small cell lung cancer and multiple thyroid lesions, classified as benign nodular goiter. Because in restating using 18F-FDG PET/CT these lesions showed an increased FDG uptake and growth progression, decision was made for fine-needle aspiration, which revealed small cell lung cancer metastasis 14 months after first tumor diagnosis.

Metastasis to the thyroid gland: Characterization and survival of an institutional series spanning 28 years

INTRODUCTION

Secondary neoplasms in the thyroid are rare. The study aim was to provide an overview of non-thyroid tumours that metastasize to the thyroid through our institutional experience.

MATERIALS AND METHODS

This study entailed a review of the pathology database searching for patients with metastasis to the thyroid at the Karolinska University Hospital between 1992 and 2019 and review of their medical files.

RESULTS

Out of 1939 surgical procedures with a histopathological diagnosis of a thyroid malignancy, 31 cases (1.6%, 65% females) with a diagnosis of metastatic epithelial neoplasms to the thyroid gland were identified. The median age at discovery of the thyroid metastasis was 68 years (range 48-85). The most common primary tumours were clear cell renal cell carcinoma (ccRCC) (36%), followed by non-small cell lung cancer (19%), oesophageal cancer (16%), head and neck malignancies (16%), malignant melanoma (10%) and unknown primary tumour (3%). The median time from the diagnosis of the primary tumour to diagnosis of the thyroid metastasis was 20 months (0-232) and was longest for patients with ccRCC (median 107 months). At 12 months after the non-thyroid metastasis diagnosis 48% had died. The longest survival was observed in ccRCC and the shortest in lung cancer. Surgical management of the metastasis was associated with improved survival (25 vs 3.8 months, p = 0.001).

CONCLUSIONS

Non-thyroid metastases to the thyroid were rare but should be suspected in patients with previous history of non-thyroid malignancy and a thyroid nodule. Prognosis was poor, but surgical management was beneficial in selected patients.

Prevalencia de tumores metastásicos en la glándula tiroides. Revisión sistemática y metanálisis

Introducción y objetivo: Los tumores metastásicos en la glándula tiroides complican el diagnóstico, el tratamiento y el pronóstico del paciente. El objetivo es conocer la prevalencia de las metástasis en la glándula tiroides referida en la literatura médica y los tumores primarios que con más frecuencia metastatizan en la glándula tiroides. Método: Se realizó una revisión bibliográfica sistemática en las bases de datos de PubMed, La Biblioteca Cochrane y Scopus. Los artículos seleccionados se dividieron en dos grupos, series clínicas de pacientes en los que se hallaron metástasis en tiroides (grupo A) y series de hallazgos de metástasis en tiroides en autopsias (grupo B). Se realizó metanálisis de prevalencia para cada grupo de artículos siguiendo el modelo de efectos aleatorios. Resultados: La prevalencia en cada grupo con su índice de confianza al 95% fue 0.00479 (0.002-0.007) para el grupo A y 0.0362 (0.014-0.059) para el grupo B. La prevalencia de metástasis halladas en autopsias fue 7,58 veces mayor que en los estudios clínicos. En el grupo A la edad media fue 60.82 y en el grupo B 57.20. En ambos grupos las metástasis halladas en tiroides fueron más frecuentes en el sexo femenino. La localización del tumor primario fue diferente en ambos grupos, en el grupo A fue el cáncer de riñón y en el grupo B el cáncer de mama. La variabilidad de la prevalencia de metástasis en tiroides en los diferentes artículos de ambos grupos hace que este estudio tuviese una alta heterogeneidad (índice I2 y Q). Los funnel plot de ambos grupos indicaron alto sesgo de publicación. Discusión: La diferente prevalencia entre series clínicas y autopsias puede implicar que la detección de metástasis en tiroides en la clínica está infradiagnosticada. La razón de esto podría ser que las metástasis intratiroideas se presentan de forma asintomática siendo diagnosticadas como hallazgo casual en autopsias. En otras ocasiones se presentan como un nódulo tiroideo años después del tumor primario, lo que condiciona el diagnóstico. Conclusiones: La prevalencia de metástasis en tiroides es superior en las series de autopsias que en series clínicas (hasta 6.67 veces más frecuente en nuestro estudio). Las metástasis intratiroideas probablemente están infradiagnosticadas por cursar sin clínica siendo diagnosticadas como hallazgo casual en autopsias. Los tumores primarios más frecuentes fueron el riñón (series clínicas) y la mama (series de autopsias).

Analysis of PAX8 immunohistochemistry in lung cancers: a meta-analysis

BACKGROUND

In this meta-analysis, we aimed to evaluate the PAX8 immunohistochemical expressions in primary lung cancers and metastatic cancers to the lung.

METHODS

We identified and reviewed relevant articles from the PubMed databases. Ultimately, 18 articles were included in this meta-analysis. PAX8 expression rates were analyzed and compared between primary and metastatic lung cancers.

RESULTS

The PAX8 expression rate in primary lung cancers was 0.042 (95% confidence interval [CI], 0.025 to 0.071). PAX8 expression rates of small cell (0.129; 95% CI, 0.022 to 0.496) and non-small cell carcinomas of the lung (0.037; 95% CI, 0.022 to 0.061) were significantly different (p=.049 in a meta-regression test). However, the PAX8 expression rates of adenocarcinoma (0.013; 95% CI, 0.006 to 0.031) and squamous cell carcinoma (0.040; 95% CI, 0.016 to 0.097) were not significantly different. PAX8 expression rates of metastatic carcinomas to the lung varied, ranging from 1.8% to 94.9%. Metastatic carcinomas from the lung to other organs had a PAX8 expression rate of 6.3%. The PAX8 expression rates of metastatic carcinomas from the female genital organs, kidneys, and thyroid gland to the lung were higher than those of other metastatic carcinomas.

CONCLUSIONS

Primary lung cancers had a low PAX8 expression rate regardless of tumor subtype. However, the PAX8 expression rates of metastatic carcinomas from the female genital organs, kidneys, and thyroid were significantly higher than those of primary lung cancers.

Infiltration of the thyroid gland by non-thyroid malignancy: A literature review reveals this to be an unusual cause of hyperthyroidism

Background

Non-thyroid malignancies that metastasize to the thyroid gland are relatively rare. At one end of the spectrum they may only be identified at the time of autopsy. At the other extreme, they may be identified during the evaluation of a progressive malignancy. Most patients who are identified as having metastases to their thyroid gland are euthyroid, but some patients may have associated hypothyroidism or hyperthyroidism. This review examines cases of hyperthyroidism associated with metastases affecting the thyroid gland.

Results

Twenty four articles describing 26 cases of malignancy-associated hyperthyroidism were identified, with the cases presenting with features suggestive of a thyroiditis and with goiter. The solid malignancies (19 cases) were mostly breast and lung cancer. Hematologic malignancies (7 cases) were also reported with a similar thyroiditis-like presentation. Patients underwent the traditional work-up for a thyroiditis, but frequently underwent other radiographic studies, in addition to radioactive iodine imaging, and frequently also underwent thyroid biopsy. The course in most patients (22/26 cases) was progression from hyperthyroidism to hypothyroidism, as the underlying malignancy progressed or thyroidectomy was performed, or the patient succumbed to their malignancy. Some patients (4 cases) became euthyroid with successful treatment of their malignancy. A subset of patients (5 cases) initially presented with severe thyrotoxicosis. Many affected patients succumbed to their underlying malignancy.

Conclusion

Malignancy-associated hyperthyroidism has a similar underlying mechanism to subacute thyroiditis, in so much as there is damage or destruction of thyroid tissue. In cases of subacute thyroiditis this damage is self-limited, and there is recovery of thyroid function. In some cases of thyroiditis associated with malignancy there may be thyroid gland recovery as the underlying malignancy is treated and controlled. However, if the malignancy progresses, eventual hypothyroidism is likely to ensue.

Thyroid metastasis from esophageal adenocarcinoma: a case report and literature review

BACKGROUND

The incidence of metastatic spread of gastrointestinal malignancies to the thyroid gland is relatively low and most of these malignancies originate from the colorectum. Thyroid metastasis originating from the esophagus is poorly documented.

CASE PRESENTATION

A 79-year-old man presented with hoarseness of voice and swallowing difficulty. Eighteen months earlier, he had undergone preoperative chemotherapy (S-1 and oxaliplatin [SOX] therapy) and subtotal esophagectomy with regional lymph nodes dissection and retrosternal narrow gastric tube reconstruction for advanced Barrett's esophageal adenocarcinoma. In the ultrasonographic examination, there was a hypoechoic, indistinct border and heterogeneous nodule in the left lobe of the thyroid gland. Pathological examination of an ultrasound-guided fine-needle aspiration showed adenocarcinoma, supporting a diagnosis of esophageal adenocarcinoma metastases in the thyroid.

CONCLUSION

This is a first case of a patient with thyroid metastasis from Barrett's esophageal adenocarcinoma after subtotal esophagectomy.

Case report: Diffuse metastatic infiltration of the thyroid by esophageal adenocarcinoma mimicking non-neoplastic thyroid disease

We report a patient who suffered from esophageal cancer that metastasized to the thyroid. There are only a handful of cases of esophageal cancer with metastases to the thyroid reported in the literature. To our knowledge, this is the first with a diffusely infiltrative pattern (the others were focal masses/nodules). This diffusely infiltrative pattern of metastatic disease is important for radiologists to be aware of because it is particularly difficult to detect and is not characteristically neoplastic by pattern. A diffuse parenchymal abnormality that is bilaterally symmetric is more commonly associated with non-neoplastic diffuse thyroid disease, such as autoimmune thyroid diseases (eg, Graves' disease). As such, in addition to the more common non-neoplastic differential diagnoses associated with diffuse thyroid disease, a diffuse thyroid parenchymal abnormality in a patient with a history of esophageal carcinoma should raise the question of diffuse metastatic infiltration.

Breast cancer metastases to the thyroid gland - an uncommon sentinel for diffuse metastatic disease: a case report and review of the literature

Background

Metastases to the thyroid are rare. The most common primary cancer to metastasize to the thyroid is renal cell carcinoma, followed by malignancies of the gastrointestinal tract, lungs, and skin, with breast cancer metastases to the thyroid being rare. Overall, the outcomes in malignancies that have metastasized to the thyroid are poor. There are no prospective studies addressing the role of surgery in metastatic disease of the thyroid. Isolated thyroidectomy has been proposed as a local disease control option to palliate and prevent the potential morbidity of tumor extension related to the airway. Here, we present a case of a patient with breast cancer metastases to the thyroid gland and discuss the role of thyroidectomy in the context of the current literature.

Case presentation

A 62-year-old Afro-Caribbean woman was diagnosed as having bilateral breast carcinoma in 2004, for which she underwent bilateral mastectomy. The pathology revealed multifocal disease on the right, T2N0(0/20)M0 grade 1 and 2 invasive ductal carcinoma, and on the left side, T3N1(2/18)M0 grade 1 invasive ductal carcinoma. Surgery was followed by adjuvant chemotherapy and regional radiotherapy. The disease was under control on hormonal therapy until 2016, when she developed cervical lymphadenopathy. The fine-needle aspiration cytology of the thyroid was reported as papillary thyroid cancer; and the fine-needle biopsy of the left lateral nodal disease was more suggestive of breast malignancy. She underwent a total thyroidectomy and a clearance of the central compartment lymph nodes and a biopsy of the lateral nodal disease. The histopathological analysis was consistent with metastatic breast cancer in the thyroid and lymph nodes with no evidence of a primary thyroid malignancy.

Conclusions

A past history of a malignancy elsewhere should raise the index of suspicion of metastatic disease in patients presenting with thyroid lumps with or without cervical lymphadenopathy. Detection of metastases to the thyroid generally indicates poor prognosis, obviating the need of surgery in an already compromised patient. An empirical thyroidectomy should be considered in select patients for local disease control.

Diffuse Thyroid Metastasis From Lung Cancer Mimicking Thyroiditis on 99mTc-Pertechnetate Scintigraphy

Possible thyroiditis was suspected in a 56-year-old man who initially presented sore throat because laboratory examinations revealed decreased serum thyroid hormone and the Tc-pertechnetate scintigraphy showed no tracer uptake by the thyroid gland. However, subsequent examination demonstrated that the absence of pertechnetate activity in the thyroid was due to complete replacement of thyroid gland by the metastasis from lung adenocarcinoma, which was unknown at the initial presentation.

Diagnosis and Treatment of Metastases to the Thyroid Gland: a Meta-Analysis

The thyroid is a rare site of clinically detectable tumor metastases; even though the gland is a highly vascularized structure, the frequency of metastases in the routine practice is less than 0.2% of all thyroid malignancies. The purpose of our meta-analysis is to evaluate the frequency of metastatic diffusion from other primary tumors to the thyroid gland and to suggest the best possible treatment through an evidence-based study. Relevant studies were identified by searching the following databases: PubMed, Scopus, and Web of Science. We selected all English-written articles published from 1995 to 2015. Studies were considered eligible if they reported the timing of metastatic spread and the site of the primary tumor in respect to the diaphragmatic region. Case reports were not included. Twenty-eight studies accounted for 514 patients. The rate of metachronous metastases was 69%. Fifty-three percent of primaries originated from the infradiaphragmatic region. Fine needle aspiration biopsy (FNAB) was done in 154 patients and 195 patients were treated mostly with surgery. A prevalence of primary tumors from the infradiaphragmatic region and of metachronous metastases was observed. Knowledge of the clinical history and the ancillary techniques can improve the sensitivity and accuracy of FNAB. Thyroidectomy may be considered a more effective treatment than radio-chemotherapy.

Malignant melanoma with synchronous thyroid metastases: case report and literature review

Thyroid metastases are rare in clinical practice. We describe the case of an 85-year-old woman who was referred to our department due to a multinodular goiter with compressive symptoms and subclinical hyperthyroidism. The patient was also undergoing evaluation for a polyp in her left nasal cavity, which was then diagnosed as a malignant melanoma of the nasal mucosa. A thoracoabdominal magnetic resonance imaging obtained for cancer staging revealed a > 50% tracheal obstruction caused by the goiter. The patient underwent simultaneous total thyroidectomy and melanoma excision. Histological analysis of the thyroid showed the presence of multiple metastatic foci from the melanoma. Due to the patient's age, a decision was made to maintain her under surveillance and administer palliative treatment if necessary. Although metastases to the thyroid are rare, they should be considered in the differential diagnosis of thyroid lesions in patients with a known primary tumor. The thyroidectomy, performed in this patient's case, allowed the diagnosis of the metastases and relief of compressive symptoms caused by the goiter.

Metastasis to the Thyroid Gland: A Critical Review

Background

Metastasis to the thyroid gland from nonthyroid sites is an uncommon clinical presentation in surgical practice. The aim of this review was to assess its incidence management and outcomes.

Methods

A literature review was performed to identify reports of metastases to the thyroid gland. Both clinical and autopsy series were included.

Results

Metastases to the gland may be discovered at the time of diagnosis of the primary tumor, after preoperative investigation of a neck mass, or on histologic examination of a thyroidectomy specimen. The most common primary tumors in autopsy studies are from the lung. In clinical series, renal cell carcinoma is most common. For patients with widespread metastases in the setting of an aggressive malignancy, surgery is rarely indicated. However, when patients present with an isolated metastasis diagnosed during follow-up of indolent disease, surgery may achieve control of the central neck and even long-term cure. Other prognosticators include features of the primary tumor, time interval between initial diagnosis and metastasis, and extrathyroid extent of disease.

Conclusions

In patients with thyroid metastases, communication among clinicians treating the thyroid and the index primary tumor is essential. The setting is complex, and decisions must be made considering the features of the primary tumor, overall burden of metastases, and comorbidities. Careful balancing of these factors influences individualized approaches.

Radiological features of metastases to the thyroid

BACKGROUND

Thyroid metastases (TM) are uncommon. Dependent on study design, the reported frequency of TM is in the range of 0.1-6% in different analyses. While clinical and histopathological features of TM were well described in the literature, radiological publications consist predominantly of isolated case reports or small series.

PURPOSE

To estimate the prevalence, clinical signs, and radiological appearances of TM.

MATERIAL AND METHODS

From 1997 to 2013, a total of 8849 patients with various disorders of the thyroid gland were treated in our institution. In 33 patients TM were diagnosed. Ultrasound (US) images were available in all patients, computed tomography (CT) of the neck in 16 patients, and magnetic resonance imaging (MRI) in nine patients.

RESULTS

Clinically, most patients (85%) presented with a painless neck mass. Primary tumors were renal cell carcinoma (79%), colorectal cancer (12%), lung cancer (3%), rhabdomyosarcoma (3%), and breast carcinoma (3%). On US, most lesions were irregular in shape with inhomogenous texture. On CT, all TM were hypodense. On T1-weighted images, most TM were inhomogenously iso-to-hyperintense in comparison to the normal thyroid tissue, and slightly hyperintense on T2-weighted images with an inhomogenous contrast enhancement.

CONCLUSION

The prevalence of TM was 0.4%. Most of the TM originated from renal cell carcinoma. The identified radiological features of TM should be taken into consideration in the differential diagnosis of thyroid lesions.

Metastatic ductal carcinoma of the breast to the thyroid gland diagnosed with fine needle aspiration: A case report with emphasis on morphologic and immunophenotypic features

Metastases to the thyroid are uncommon [<0.2% of thyroid fine needle aspirations (FNA)]. Of metastases to the thyroid, breast carcinoma is relatively common. The diagnosis of metastasis to the thyroid has important therapeutic and prognostic implications. To our knowledge, a morphologic and immunophenotypic comparison of metastatic ductal carcinoma of the breast and primary thyroid carcinomas has not been reported. Here, we report the case of a 37-year-old female with a history of metastatic ductal carcinoma of the breast (modified Bloom-Richardson grade 2; ER+, PgR+, HER2+) diagnosed 6 years prior. She developed hoarseness, prompting a CT scan. Multiple thyroid nodules were found, including a 1.5 cm hypoechoic, solid, irregularly-shaped nodule. On FNA, cells were arranged singly and in crowded groups, varied in size and degree of pleomorphism, and exhibited rare nuclear grooves, inconspicuous nucleoli, and rare intracytoplasmic lumina with no nuclear pseudoinclusions or colloid (Figs. 1A and B). These findings raised the differential of papillary thyroid carcinoma (Fig. 1C), follicular neoplasm (Fig. 1D), medullary carcinoma (Fig. 1E), parathyroid (Fig. 1F), and metastatic breast carcinoma. Immunostaining for GATA-3 (+), ER (+), PAX-8 (-), and TTF-1 (-) was consistent with metastatic breast carcinoma (Fig. 2). We conclude that metastatic breast carcinoma to the thyroid may morphologically mimic primary thyroid carcinoma on FNA; a panel of immunomarkers, such as GATA-3, hormonal marker(s), PAX-8, and TTF-1, may be useful in some cases. GATA-3 immunostaining for metastatic breast carcinoma was helpful in our case and has not been previously reported in a thyroid metastasis sampled by FNA. Diagn. Cytopathol. 2016;44:530-534. © 2016 Wiley Periodicals, Inc.

Diagnosis of Metastasis to the Thyroid Gland: Comparison of Core-Needle Biopsy and Fine-Needle Aspiration

OBJECTIVES

Early detection and diagnosis of metastasis to the thyroid gland is important. This study aims to evaluate the clinical value of core-needle biopsy (CNB) by comparing the results of CNB and fine-needle aspiration (FNA) in patients with clinically suspected metastasis to the thyroid gland.

STUDY DESIGN

Case series with chart review.

SETTING

Tertiary referral practice.

SUBJECTS

Fifty-two thyroid nodules from 52 patients with clinically suspected metastasis to the thyroid gland (mean age, 62.8 years).

METHODS

Of these 52 patients, FNA was initially used in 41 patients and CNB in 20 patients (11 patients as the initial approach and 9 patients after inconclusive FNA results). Ultrasound features of metastasis to the thyroid gland were evaluated. The diagnostic performance, repeated diagnostic examination rate, and diagnostic surgery rate were evaluated for FNA and CNB.

RESULTS

Among these 52 patients, 46 were diagnosed with thyroid metastases and 6 were diagnosed with primary thyroid cancer. Common ultrasound features were an ovoid to round shape (58.7%), ill-defined margin (56.5%), hypoechogenicity (65.2%), and no calcifications (87.0%). Core-needle biopsy achieved a significantly higher sensitivity than FNA (100.0% vs 58.6%, P = .008) without any false-negative results. Both the repeated diagnostic examination rate and the diagnostic surgery rate were significantly lower in CNB than in FNA (5.0% vs 46.3%, P = .001, and 5.0% vs 34.1%, P = .013, respectively).

CONCLUSIONS

In cases of known rare primary malignancy, nontypical ultrasound features of primary thyroid malignancy, and need for an additional immunohistochemical analysis, CNB may be primarily considered.

Secondary tumors involving the thyroid gland: A multi-institutional analysis of 28 cases diagnosed on fine-needle aspiration

BACKGROUND

Fine-needle aspiration (FNA) is routinely used to evaluate primary thyroid lesions (PTLs), however, its role in diagnosing secondary thyroid neoplasms (STNs) has not been extensively studied. The goal was to examine the clinical and cytopathologic features of STNs diagnosed on FNA.

METHODS

The clinico-pathologic features of 28 STNs were analyzed. All PTLs, lymphomas, and locally invasive tumors were excluded.

RESULTS

There were 28 STNs (0.18% incidence) out of 15,800 thyroid FNAs (12 males, 16 females, 32 - 85 years), all occurring metachronously (3 weeks-20 years, average 78.3 months) comprising 24 (85.7%) metastatic carcinomas (14 [50%] renal; 4 [14.3%] head and neck squamous cell carcinomas, 3 [10.7%] breast, and 1 [3.6%] colorectal, uterine serous carcinoma, and lung adenosquamous carcinoma, respectively), 3 sarcomas (10.7%) and 1 melanoma (3.6%).

CONCLUSIONS

STNs are rare and diverse tumors which may occur decades after primary malignancy. Renal carcinomas are the most common. Prior history of malignancy, high index of suspicion, and attention to key distinguishing cytologic clues are critical for accurate diagnosis.

Collision tumors of the thyroid: A case report and review of the literature

BACKGROUND

Collision tumors of the thyroid are a rare pathology that present a diagnostic and treatment challenge. In this report, we present an interesting case and a review of the current literature as to inform management.

METHODS AND RESULTS

An 88-year-old woman presented with acute airway compromise and vocal cord paralysis. CT identified a thyroid mass and widespread metastasis. Histopathology identified the lesion as a collision tumor consisting of a squamous cell carcinoma (SCC) and papillary thyroid carcinoma. The patient was managed with surgery and palliative radiotherapy. However, she died from complications of a lower respiratory tract infection. We also present a review of the literature with 33 cases reviewed.

CONCLUSION

Management of collision tumors is complex because of the duality of the pathology. They should be managed in a multidisciplinary team setting and treatment should be patient specific. Generally, the most aggressive neoplasm should guide treatment. We recommend surgical management with adjunct therapy.

Synchronous diagnosis of metastatic cancer to the thyroid is associated with poor prognosis

The incidence and histopathological characteristics of metastatic cancers to the thyroid (MCT) are different in various geographic areas. The aim of this study was to elucidate the clinical features of MCT, including histocytological diagnosis and therapeutic outcomes. A retrospective analysis of patients with thyroid cancer treated and followed up at the Chang Gung Medical Center in Linkou was performed. Among 3957 patients with thyroid cancer, a total of 56 patients with MCT were evaluated. Of them, 47 patients (83.9 %) were diagnosed with malignancy or suspected malignancy via fine needle aspiration cytology of the thyroid. Synchronous primary cancers were diagnosed in 44 of the patients with MCT. Of the MCT, metastasis of lung cancer to the thyroid was the leading category. Other primary sites of MCT were the head and neck, gastrointestinal tract, kidneys, breast, cervix, and unknown primary site. The mean 5-, 10-, 20-, and 60-month survival rates were 46.4, 32.1, 21.4, and 7.9 % for the patients. Patients with metachronous thyroid carcinoma had significantly better survival than patients with synchronous cancer. In conclusions, the incidence of MCT in patients with thyroid cancer is low; however, the prognosis of patients with MCT is poor, especially in patients diagnosed with synchronous primary tumors. In this study, MCT commonly originated in organs located near the thyroid, such as the lungs, head, and neck. Close monitoring of these malignancies may improve the prognosis of patients with MCT in the future.

Metachronous intrathyroid-only metastases from breast cancer

Abstract: 

Thyroid-only metastases from other primary cancers are rare and associated with poor prognosis. Breast cancer typically metastasizes to lymph nodes, liver and lungs, while isolated metastases to the thyroid gland are exceptionally rare and often difficult to suspect and differentiate from thyroid cancer (and most frequently poorly differentiated thyroid cancer), even by using fine needle aspiration. A patient with a history of breast cancer (4 years ago) with thyroid-only metastases is presented. Diagnostic and therapeutic problems are discussed and the relevant literature is briefly reviewed. The novelty of this data is that intrathyroid-only metastases from breast cancer are extremely uncommon and indicate generalized disease, and preoperative diagnosis can be difficult, even by using ultrasound-guided fine needle aspiration.

Clinical significance of patterns of incidental thyroid uptake at (18)F-FDG PET/CT

Incidental uptake of 2-[(18)F]-fluoro-2-deoxy-d-glucose ((18)F-FDG) in the thyroid gland is not uncommonly encountered in day-to-day practice of oncological (18)F-FDG positron-emission tomography/computed tomography (PET/CT). These are often felt to be "nuisance lesions" by referring clinicians and radiologists alike. However, recognition of the importance of different patterns of FDG uptake in the thyroid gland and knowledge of the possible underlying aetiologies are crucial in ensuring that patients are managed appropriately in the clinical context of their primary diagnosis, as the underlying pathological condition may be clinically important in a significant minority of such cases. This review describes the various patterns of (18)F-FDG uptake within the thyroid and discusses the clinical significance and possible impact on patient management. Incidental low-grade homogeneous diffuse increased thyroid (18)F-FDG uptake is usually seen in the patients with chronic thyroiditis, Grave's disease, and hypothyroidism. Thyroid function tests and antibody profiling are advised in these patients. Incidental focal (18)F-FDG thyroid uptake should raise the possibility of underlying malignancy. Ultrasound with or without fine-needle aspiration cytology is usually recommended for the evaluation of these lesions. Heterogeneous uptake with prominent focal uptake in the thyroid should be further evaluated to exclude malignancy.

Metastasis of distal esophageal carcinoma to the thyroid with presentation simulating primary thyroid carcinoma: a case report and review of the literature

Metastasis to the thyroid is extremely rare. There is a lack of awareness of and adequate preparation for this situation, especially in an individual without a past history of malignancy. We describe a rare case of a 61-year-old man in whom a primary distal esophageal carcinoma gave rise to a metastatic palpable mass in the thyroid gland. Palliative bilateral near-total thyroidectomy was performed with pathology showing squamous cell carcinoma and tracheostomy was carried out simultaneously due to airway compression with related symptoms. A review of the literature only reveals 4 similar cases. Secondary neoplasm of the thyroid mimicking a primary malignant lesion is seldom encountered, however, in order to make appropriate treatment, the most critical problem is to distinguish the difference between the above two and the final diagnosis can only be confirmed on pathologic examination. Although the prognosis of thyroid metastasis is commonly felt to be poor, improvement of living quality and prolongation of survival may be obtained in such patients through correct diagnosis and treatment.

Cytologic diagnosis of metastatic alveolar rhabdomyosarcoma to the thyroid gland by fine-needle aspiration

BACKGROUND

Metastases to the thyroid gland, although rare, are important entities to consider when evaluating malignant cells on a thyroid fine-needle aspiration (TFNA) specimen. Cellular TFNA specimens with small round blue cells should prompt a broad differential: florid lymphocytic thyroiditis, lymphoma, metastases, as well as primary thyroid malignancies with similar morphologies such as poorly differentiated (insular) and medullary carcinomas. Age, clinical presentation and prior history must be considered in every case.

CASE REPORT

We report, to the best of our knowledge, the first case of metastatic alveolar rhabdomyosarcoma (ARMS) to the thyroid gland, definitively diagnosed by TFNA. A 21-year-old female patient presented with a large mass in the right lobe of the thyroid. Her past history was significant for ARMS diagnosed 24 months earlier, currently in remission after successfully completing 40 weeks of chemoradiation therapy. The diagnosis of metastatic ARMS in the TFNA prompted a more thorough examination revealing previously unknown additional sites of metastases.

CONCLUSION

Metastases to the thyroid gland are uncommon but should be considered in cases where atypical morphology is encountered. Small round blue cell tumors can metastasize to the thyroid gland, and clinical presentation, morphology, immunohistochemistry and molecular studies are helpful in differentiating between them.

Thyroid metastasectomy

Metastases to the thyroid gland are uncommon. Renal, lung, breast, and colon cancer and melanoma are the most common primary diseases implicated. Few retrospective series have been reported. Treatment decisions must be individualized, and will depend on the state of systemic disease. Selected patients could benefit from surgical treatment. Although most patients selected for surgery will not be cured, the aim of surgery is to avoid the complications of uncontrolled central neck disease.

Metastatic carcinoma to the thyroid gland: a single institution 20-year experience and review of the literature

The thyroid gland is an uncommon site for metastatic disease but cases have been well-documented in the literature, particularly in autopsy series. A retrospective review of surgical pathology and autopsy pathology database for patients with metastatic carcinoma to the thyroid was performed at the University of Massachusetts Medical Center between January 1993 to January 2013. We identified a total of 10 patients with metastatic carcinoma to the thyroid; 6 were in surgical pathology specimens out of a total of 1,295 thyroid carcinoma (0.46 %) and 4 were diagnosed at autopsy out of a total of 2,117 (0.19 %) autopsy cases during this period. Cases with direct extension of the tumor into the thyroid from local primary sites such as larynx, esophagus or soft tissues of the neck were excluded. The primary tumors in these cases comprised of four lung carcinomas, three colorectal carcinomas, a renal cell carcinoma, a pleural malignant mesothelioma, and an unknown primary. Therefore, it is important to keep intrathyroidal metastases in the differential diagnosis when evaluating a thyroid nodule, particularly in patients with a previous history of malignancy. Furthermore, a literature review reveals over 1,400 cases have been previously reported, with the most common malignancies from the kidney (34 %), lung (15 %), gastrointestinal tract (14 %), and breast (14 %).

Thyroid gland metastasis from small cell lung cancer: an unusual site of metastatic spread

Metastasis to the thyroid gland is uncommon compared with the frequency of primary thyroid tumors. The primary sites of metastatic thyroid tumors usually include the breast, lung, kidney and stomach. Among lung cancer types metastasizing to the thyroid, adenocarcinomas are the commonest followed by squamous and large cell carcinomas. Small cell lung carcinoma has not been frequently reported to cause thyroid metastatic deposits. Herein, we describe a patient with small cell lung cancer who developed metastatic lesions to the thyroid and brain simultaneously. Thyroid ultrasonography-guided fine-needle aspiration cytology (US-FNAC) and particularlyimmunocytochemistry documented metastasis from primary lung cancer. Clinical, cytopathological and therapeutic aspects of this unusual site of extrathoracic metastatic disease are discussed laying special emphasis on the paramount importance of the immunocytochemistry in distinguishing primary thyroid tumors from thyroid metastasis due to lung cancer.

A rare primary tumor of the thyroid gland: report a new case of leiomyosarcoma and literature review

Primary leiomyosarcomas of the thyroid gland are extremely rare. we report a case of a 72 year-old women with a painful growing mass of the left neck with skin fistula. The patient underwent a lobectomy. The tumor histology showed spindle-shaped cells arranged in interlacing fascicles that expressed desmine and Hcaldesmone, but were negative for cytokeratins and thyroglobulin. Total body CT scan didnt show any other tumor. The patient died two months after surgery. Primary thyroid leiomyosarcoma may be mistaken for other tumors, such as anaplastic or medullary carcinomas. Therefore, the diagnosis is difficult and requires numerous clinical, radiological, and pathological investigations.

Thyroid lymphoma: correlation of radiologic and pathologic features

OBJECTIVES

The purpose of this study was to correlate the clinicoradiologic and pathologic features of thyroid lymphoma and to identify the most useful diagnostic method for thyroid lymphoma as the first line.

METHODS

Our study population included 16 patients with a diagnosis of thyroid lymphoma by fine-needle aspiration, core biopsy, or surgery from 1995 to 2010. We retrospectively reviewed imaging and medical records. Sonographic findings were correlated with histopathologic results.

RESULTS

Of the 16 patients, primary lymphomas were found in 13 and secondary in 3. The mean ages of the patients with primary and secondary lymphomas were 60.8 and 42.7 years, respectively. Most patients with primary lymphomas had symptoms of rapid neck swelling or a mass sensation. All primary lymphomas revealed non-Hodgkin B-cell lymphoma, and secondary lymphomas included a B-cell origin in 2 and a T-cell origin in 1. On sonography, 10 (77%) of 13 primary lymphomas showed diffuse heterogeneous hypoechoic parenchyma with intervening echogenic septa-like structures, whereas all secondary lymphomas showed markedly hypoechoic nodules. Markedly hypoechoic parenchyma was correlated with lymphoepithelial lesions and neoplastic cells, whereas the intervening echogenic septa-like structures were consistent with fibrosis on pathologic examination. The exact diagnosis of thyroid lymphoma was possible with core biopsy in all 9 cases (100%) but with fine-needle aspiration in only 3 of 10 (30%), which included 7 under sonographic guidance and 3 under palpation (P = .0030).

CONCLUSIONS

Diffuse hypoechoic parenchyma with intervening echogenic septa on sonography under the impression of a primary thyroid lymphoma, particularly in the setting of a rapidly enlarging mass, should prompt core biopsy rather than fine-needle aspiration.

Neuroendocrine tumors presenting with thyroid gland metastasis: a case series

INTRODUCTION

Autopsy series have shown that metastasis to the thyroid gland has occurred in up to 24% of patients who have died of cancer. Neuroendocrine tumors may metastasize to thyroid gland.

CASE PRESENTATIONS

Case 1 was a 17-year-old Turkish woman who was referred from our Endocrinology Department for a thyroidectomy for treatment of neuroendocrine tumor metastasis. She was treated with a bilateral total thyroidectomy. Histopathological examination results were consistent with a neuroendocrine tumor; neoplastic cells showed strong immunoreactivity to chromogranin A and synaptophysin, but the immunohistochemical profile was inconsistent with medullary thyroid carcinoma in that the tumor was negative for calcitonin, carcinoembryonic antigen, and thyroid transcription factor-1.Case 2 was a 54-year-old Turkish woman who presented with a 3-cm nodule on her right thyroid lobe. She had undergone surgery for a right lung mass four years previously. After a right pneumonectomy, thymectomy and lymph node dissection, a typical carcinoid tumor was diagnosed. Under ultrasonographic guidance, fine needle aspiration biopsy of her right thyroid pole nodule was performed and the biopsy was compatible with a neuroendocrine tumor metastasis. She was treated with a bilateral total thyroidectomy. Histopathological examination indicated three nodular lesions, 5 cm and 0.4 cm in diameter in her right lobe and 0.1 cm in diameter in her left lobe. The tumors were consistent with a neuroendocrine phenotype, showing strong immunoreactivity to chromogranin A and synaptophysin.

CONCLUSION

Thyroid nodules detected during follow-up of neuroendocrine tumor patients should be thoroughly investigated. A fine needle aspiration biopsy of the thyroid confirms the diagnosis in most cases and leads to appropriate management of those patients and may prevent unnecessary treatment approaches.

Thyroid cyst wall atypia in a patient with a history of malignant melanoma: a pitfall in fine-needle aspiration cytology

We present an interesting case report from a patient with a history of desmoplastic malignant melanoma (MM), who presented with a thyroid nodule. The patient's clinical diagnosis included a benign thyroid nodule versus a primary thyroid malignancy or metastatic MM. Fine-needle aspiration biopsy showed highly atypical spindle cells suspicious for metastatic MM. The acellular cell block prevented further studies such as immunohistochemical analysis. The patient underwent surgical excision of the mass, which showed a benign cystic thyroid nodule with an atypical cyst lining. Here, we report the presence of atypical cyst-lining cells in a patient with diagnosis of MM. The atypical cytology of the cyst-lining cells has been reported in the English literature; however, presence of significant cytological atypia, especially in a patient with a history of another malignancy, can be problematic. The cytopathologist should be aware of this entity and its diagnostic pitfalls.

Thyroid gland metastasis arising from primary liver cholangiocarcinoma: The first case report involving surgical operation

INTRODUCTION

A primary cancer causing thyroid metastasis is extremely rare. In western countries, the most common primary tumors causing thyroid metastases include kidney, lung, breast, and gastrointestinal cancers. In contrast, breast is the most common primary site, followed by kidney, colon, and lung cancers in Korea. To the best of our knowledge, surgically confirmed thyroid metastasis from cholangiocarcinoma has not been reported. Herein, we report the first case of thyroid metastasis secondary to cholangiocarcinoma on which surgery was performed.

PRESENTATION OF CASE

A 55-year-old man was diagnosed with hepatic malignancy in December 2008. He subsequently received 2 cycles of transarterial chemoembolization and 4 cycles of radio-frequency ablation between 2008 and 2010. At follow-up in January 2011, brain metastasis was identified in the right parietal area secondary to cholangiocarcinoma. In April 2011, the patient was found to have palpable masses on the left thyroid and lateral neck. The patient subsequently underwent total thyroidectomy followed by left radical neck dissection. Intraoperatively, an ill-defined mass measuring 6.0 cm was found infiltrating the subcutaneous tissue into the prevertebral fascia. Microscopic and immunohistochemical findings confirmed that the thyroid masses and lymph nodes were metastatic cholangiocarcinoma.

DISCUSSION

Positive immunohistochemical staining for cytokeratin 7, cytokeratin 19, and AFP and negative results for TG, TTF-1, and cytokeratin 20 can be definitely helpful in arriving at a correct diagnosis.

CONCLUSION

To the best of our knowledge, this is the first case report on surgically resected thyroid and lateral neck metastases secondary to cholangiocarcinoma.

Detection of Thyroid Metastasis of Renal Transitional Cell Carcinoma Using FDG PET/CT

A 69-year-old man who was diagnosed with renal transitional cell carcinoma (TCC) underwent F-18 fluorodeoxyglucose (FDG) positron emission tomography with computed tomography (PET/CT) for detecting recurrence after chemotherapy. FDG PET/CT revealed multiple new hypermetabolic lesions in many places, including the right thyroid gland. Biopsy of the thyroid lesion was performed, and a diagnosis of metastatic TCC was made. We could detect thyroid metastasis of renal TCC by FDG PET/CT.

Surgical management of metastases to the thyroid gland

BACKGROUND

Metastases to the thyroid gland are uncommon, with rates reported between 0.02% and 1.4% of surgically resected thyroid specimens. Our goal was to present our experience with surgical management of metastases to the thyroid gland.

METHODS

Twenty-one patients with metastatic disease to the thyroid were identified from a database of 1,992 patients with thyroid cancer who had surgery during 1986-2005. Patient, tumor, treatment, and outcome details were recorded by analysis of charts. The median age at time of surgery was 68 (range, 39-83) years; 12 were men and 9 were women.

RESULTS

All patients were managed by surgery, including lobectomy in ten patients, total thyroidectomy in six, completion thyroidectomy in two, and subtotal thyroidectomy in one. In two patients, the thyroid lesion was found to be unresectable at the time of surgery. Histopathology revealed renal cell carcinoma in ten, malignant melanoma in three, gastrointestinal adenocarcinoma in three, breast cancer in one, sarcoma in one, and adenocarcinoma from an unknown primary site in three patients. Seventeen patients have died. The cause of death in all 17 was widespread metastatic disease from their respective primary tumors. The median survival from surgery to death or last follow-up was 26.5 (range, 2-114) months.

CONCLUSIONS

In patients with metastases to the thyroid gland, local control of metastatic disease in the central compartment of the neck can be successfully achieved with minimal morbidity with surgical resection in selected patients.

Squamous cell carcinoma of the thyroid gland: primary or secondary disease?

OBJECTIVE

To review the aetiopathogenesis, clinical characteristics, immunohistochemical profile, prognosis and treatment options for primary thyroid squamous cell carcinoma, and to compare it with squamous cell carcinoma metastatic to the thyroid, thus providing the reader with a framework for differentiating primary and secondary disease.

METHOD

Review of English language literature from the past 25 years.

SEARCH STRATEGY

A search of the Medline, Embase and Cochrane databases (April 1984 to April 2009) was undertaken to enable a comprehensive review.

RESULTS

After applying strict criteria for the diagnosis of primary thyroid squamous cell carcinoma, 28 articles were identified reporting 84 cases. When reviewing secondary thyroid squamous cell carcinoma, we only analysed cases of squamous cell carcinoma metastatic to the thyroid gland, and found 28 articles reporting 78 cases.

CONCLUSION

It is possible to differentiate between primary and secondary thyroid squamous cell carcinoma, on the basis of combined evidence from clinical examination and endoscopic, pathological and radiological evaluation. Such differentiation is important, as the prognosis for primary squamous cell carcinoma is uniformly poor irrespective of treatment, and the most suitable option may be supportive therapy. Treatment for secondary squamous cell carcinoma of the thyroid varies with the site and extent of spread of the primary tumour.

Tumor-to-tumor metastasis: Renal cell carcinoma metastatic to papillary carcinoma of thyroid-report of a case and review of the literature

Metastatic disease to thyroid gland is a rare event. Although renal cell carcinoma (RCC) has been reported to metastasize the thyroid gland, metastatic RCC to a thyroid neoplasm is very unusual. We report a case of a 68-year-old man with history of RCC who presented with a 2.5-cm thyroid nodule. Histologic examination demonstrates a renal cell carcinoma metastatic to a papillary carcinoma of the thyroid. The clinicopathologic features of metastatic disease into a thyroid gland neoplasm are shown, and a review of the literature is presented.

Restriction of drinking water abrogates splanchnic vasodilation and portal hypertension in portal vein-ligated rats

Portal hypertension is associated with splanchnic vasodilation which is claimed responsible for the maintenance of chronically elevated portal pressure. Vasopressin analogues are used in the treatment of acute variceal bleeding, since they effectively reduce splanchnic blood flow and portal pressure. Dehydration stimulates the release of endogenous vasopressin release. Here we compared the effects of deprivation of drinking water for 18 h with those of vasopressin infusion on mesenteric hemodynamics in portal vein-ligated (PVL) and sham-operated (SHAM) rats. Blood flow in the superior mesenteric artery was measured with the ultrasonic transit time shift technique. Deprivation of drinking water had no hemodynamic effects in SHAM rats, but completely reversed the mesenteric hyperemia and portal hypertension in PVL rats to figures measured in SHAM rats, without altering blood pressure. Similarly, intravenous infusion of low doses of arginine vasopressin (1-10 pmol/min) selectively reduced mesenteric blood flow in PVL rats but had little effect in SHAM rats. These data suggest that control of water balance or aquaretic drugs might have beneficial effects on splanchnic hemodynamics and portal pressure in advanced liver disease, possibly by stimulating endogenous vasopressin release.

Solitary intrathyroidal metastasis of renal clear cell carcinoma in a toxic substernal multinodular goiter

Introduction

Thyroid gland is a rare site of clinically detectable tumor metastasis.

Case report

A 71-year-old woman was referred to our department for an evaluation of toxic multinodular substernal goiter. She had a history of renal clear cell carcinoma of the left kidney, which had been resected 2 years previously. US confirmed the multinodular goiter. Total thyroidectomy with neuromonitoring was performed on March 2008. A histological examination revealed a solitary metastasis of a clear cell renal cancer in a diffuse multinodular goiter. No distant metastases are detected.

Conclusion

Although uncommon, it is important for the endocrine surgeon and endocrine oncologist to be able to recognize and differentiate intrathyroid metastases from more primary common thyroid neoplasms. The diagnosis can be suspected if the patient has a thyroid tumor and a past history of extrathyroid cancer. These tumors, on the whole, tend to behave more aggressively and, in most cases, the use of multimodality therapy is recommended.