Ectopic thyroid tissue: anatomical, clinical, and surgical implications of a rare entity

Clinical use of thyroglobulin: not only thyroid cancer

Thyroglobulin (TG) is a dimeric glycoprotein produced exclusively by mature thyroid tissue and stored within the follicular lumen. It is essential for the organification of iodine and the production of thyroid hormones. The concentration of TG in the bloodstream varies between individuals and depends on factors such as thyroid mass, stimulation of the gland by thyrotropin or autoantibodies, and tissue destruction. TG is essential to monitor patients with differentiated thyroid cancer; however, its use is not limited only to this clinical entity. Measurement of circulating TG can provide better insight into numerous clinical scenarios, such as destructive thyroiditis, presence of ectopic thyroid tissue, thyroid trauma, factitious thyrotoxicosis, or iodine nutrition. Lately, TG has found its new clinical use in immune checkpoint-related thyroid dysfunction. TG measurement should be performed carefully in patients with antithyroglobulin antibodies due to possible laboratory interferences. In this review, we offer a summary of current knowledge about the clinical use of TG and the implications it brings to daily practice.

Ectopic thyroid in the hepatoduodenal ligament: a case report and literature review

Ectopic thyroid arises from abnormal development of thyroid primordial tissues as it migrates to the lower interstitium during the embryonic period, which can occur at various locations during the descent process. However, ectopic thyroid in the subdiaphragmatic area is extremely rare. In this case, we report a case of ectopic thyroid located in the hepatoduodenal ligament. The 60-year-old female patient was admitted to hospital with gallbladder stones and cholecystitis. Preoperative imaging showed a mass in the hepatoduodenal ligament. As the patient declined a needle biopsy of the mass, the nature of the mass remained unclear prior to surgery. The patient subsequently underwent laparoscopic cholecystectomy and exploratory resection of the mass. The histopathology of the resected mass showed the characteristics of ectopic thyroid, and immunohistochemical staining revealed positive expression of thyroid transcription factor-1 and thyroglobulin. The diagnosis of ectopic thyroid was established. Upon confirming the diagnosis, comprehensive neck examination revealed the presence of a normally functioning thyroid gland. Throughout the four-year follow-up period, the patient's thyroid ultrasonography and thyroid function tests indicated no abnormalities. Ectopic thyroid in the hepatoduodenal ligament and surrounding areas is an extremely rare clinical abnormality, achieving a clear diagnosis before initiating treatment offers diagnostic and treatment insights and clues for clinicians when differentiating masses within this region.

Radioiodine whole body scan pitfalls in differentiated thyroid cancer

PURPOSE

whole body scan (WBS) performed following diagnostic or therapeutic administration of I-131 is useful in patients with differentiated thyroid carcinoma. However, it can be falsely positive in various circumstances. We aimed to report a series of pitfalls in a clinical perspective.

METHODS

A search in the database PubMed utilizing the following terms: "false radioiodine uptake" and "false positive iodine 131 scan" has been made in January 2023. Among the 346 studies screened, 230 were included in this review, with a total of 370 cases collected. Physiological uptakes were excluded. For each patient, sex, age, dose of I-131 administered, region and specific organ of uptake and cause of false uptake were evaluated.

RESULTS

370 cases of false radioiodine uptake were reported, 19.1% in the head-neck region, 34.2% in the chest, 14.8% in the abdomen, 20.8% in the pelvis, and 11.1% in the soft tissues and skeletal system. The origin of false radioiodine uptake was referred to non-tumoral diseases in 205/370 cases (55.1%), benign tumors in 108/370 cases (29.5%), malignant tumors in 25/370 cases (6.7%), and other causes in 32/370 cases (8.7%).

CONCLUSIONS

WBS is useful in the follow-up of patients with differentiated thyroid carcinoma, however it can be falsely positive in various circumstances. For this reason, it is critically important to correlate the scintigraphic result with patient's medical history, serum thyroglobulin levels, additional imaging studies and cytologic and/or histologic result.

Primary Intrathoracic Ectopic Papillary Thyroid Carcinoma, Presenting With Thoracic Spine Metastasis: A Case Presentation and Literature Review

Thyroid cancer in ectopic thyroid tissue is a very rare entity. We report a patient with papillary thyroid cancer arising from upper mediastinal ectopic thyroid tissue. The patient presented with thoracic spine metastasis with cord compression. The patient was a 67-year-old woman, who presented with upper back pain. Magnetic resonance imaging (MRI) showed suspected metastatic disease in the second and third thoracic vertebrae (T2 and T3). She underwent laminectomy and decompression surgery at the T1-T3 level. The final pathology report showed metastatic thyroid carcinoma with papillary features. She underwent external beam radiation to the affected spine. Computerized tomography (CT) scan of the chest, abdomen, and pelvis showed a 3.0 × 2.8 × 2.3 cm soft-tissue mass in the left superior mediastinum extending into the supraclavicular region. Fluorodeoxyglucose-positron emission tomography (FDG-PET) scan showed hypermetabolic foci in the upper mediastinum. Fine needle aspiration (FNA) of the upper mediastinal mass was consistent with papillary thyroid cancer. Molecular testing from the FNA sample using Thyroseq V3 showed SQSTM1NTRK3 chromosomal rearrangement. A total thyroidectomy was performed. Pathology of the resected thyroid was benign. Pathology of the mediastinal mass showed a papillary thyroid carcinoma with focal tall cell features, forming a 4 × 2.5 × 2.5 cm mass. Surgery was followed by ablation with 100 millicuries (mci) of radioactive iodine (I-131) and external beam radiation. This case highlights the presentation of primary intrathoracic papillary thyroid cancer with SQSTM1-NTRK3 chromosomal rearrangement and the challenges in the diagnosis and management of this unique case. This patient had a very aggressive disease presentation that required multimodal treatment, including thoracic spine decompression, total thyroidectomy, primary intrathoracic goiter resection, high-dose radioactive iodine treatment, and external beam radiation to the affected spine area. SQSTM1-NTRK3 chromosomal rearrangement can be targeted by medications such as larotrectinib and endtrectinib.

Radioiodine Therapy: Alternative for the Treatment of Complicated Thyroid Ectopia

Thyroid ectopy is the presence of thyroid tissue outside its normal cervical location. Clinical manifestations of thyroid ectopy are varied. The latter complications can be life-threatening. Emergency treatment is often surgical or endoscopic. We report a case of a 26-year-old man with tracheal thyroid ectopy, complicated by respiratory distress, in whom conventional treatments were not feasible. The patient was treated with radioiodine-131 administered in liquid form. The final control showed the complete resolution of the intra-tracheal mass. Intra-tracheal thyroid ectopy is a rare anomaly in which surgery is the traditional treatment. In certain cases where surgery is not feasible or refused, treatment with iodine-131 is a safe and effective alternative for the removal of ectopic thyroid tissue. The aim of our work is to show the significant efficiency of radioiodine therapy as an alternative for the treatment of complicated thyroid ectopia.

Benign lesions of the mediastinum

Mediastinal tumours represent a heterogeneous group of entities derived from the manifold structures located in or adjacent to the mediastinum. Due to the occurrence of some of these tumours in characteristic mediastinal compartments, an anatomical subdivision of the mediastinum in the prevascular (anterior), visceral (middle), and paravertebral (posterior) is helpful for the differential diagnosis. Benign anterior mediastinal tumours linked to an enlargement of the thymic gland mainly consist of thymic cysts and several types of thymic hyperplasia: true thymic hyperplasia, rebound hyperplasia, lymphofollicular hyperplasia, and so-called thymic hyperplasia with lymphoepithelial sialadenitis (LESA)-like features. Mature teratomas, ectopic (para)thyroid tissue, and benign thymic tumours such as thymolipoma or thymofibrolipoma represent further typical tumours of the anterior mediastinum. Pericardial, bronchogenic, or oesophageal duplication cysts predominate in the middle mediastinum, whereas neurogenic tumours and myelolipomas are characteristic findings in the posterior compartment. Vascular tumours, lipomas, adenomatoid tumours, Castleman disease, or mediastinitis are further examples of less frequent tumours or tumorous lesions affecting the mediastinum. This review focuses on benign mediastinal lesions with an emphasis on benign tumours of the thymus. Besides histology, characteristic epidemiological and clinical aspects prerequisite for the correct diagnosis and patient management are discussed.

Ectopic thyroid carcinoma in the nasal septum: A case report

INTRODUCTION AND IMPORTANCE

Ectopic thyroid carcinoma often occurs in the neck, and metastatic carcinoma of the nasal cavity and sinuses is extremely rare.

CASE PRESENTATION

An 11-year-old female was admitted to the hospital for one week due to nasal pain without an obvious cause and blood in the nose. A pale red mass with a peduncle at the back end of the right nasal septum was seen during the operation. Immunohistochemistry showed low-grade papillary thyroid carcinoma.

CLINICAL DISCUSSION

Surgeons should be alert to the possibility of ectopic thyroid tissue and related diseases, Patients with suspected malignant lesions should undergo routine pathological examination, and even a normal thyroid should be checked for malignant changes to avoid negative outcomes.

CONCLUSION

Although nasal endoscopic surgery is mature, for tumors with unclear properties, it is still necessary to undergo routine pathological examination to avoid habitual errors.

Pitfalls of Iodine-131 Whole-Body Scan Mimicking Metastases in Differentiated Thyroid Carcinoma: A Case Series

Thyroid cancer is the most common endocrine malignant tumor and accounts for 1% of all cancers. Management of differentiated thyroid carcinoma is total thyroidectomy, followed by iodine-131 (I-131) radioactive iodine (RAI) therapy for thyroid remnant tissue. I-131 whole-body scan helps in the follow-up evaluation in remnant, residual, and recurrence cases. Principle of uptake of I-131 is through sodium-iodide symporter expression on the cells. Physiological uptake of iodine is usually seen in salivary glands and gastrointestinal tract, and false-positive uptakes are seen in lesions such as mucinous cystadenoma, struma ovarii, hepatic, renal, thymic, and meibomian cysts. Here, we present the review of literature of series of cases observed in our department presenting with false-positive uptake of RAI in vertebral hemangioma, lipoma, sinusitis, teratoma, and uterine leiomyoma.

The clinicopathological features, treatment outcomes and follow-up results of 47 ectopic thyroid gland cases: a single-center retrospective study

Background

Ectopic thyroid gland (ETG) is an uncommon clinical condition, presenting various challenges and limitations in its regulate diagnosis and treatment currently. This study aims to enhance our understanding of ETG and improve the strategies for its diagnosis and treatment.

Methods

The retrospective single-center study was conducted, encompassing clinical data from ETG patients screened at our institution between 2013 and 2022. Patients were categorized based on the location of the disease, and follow-ups were performed on each.

Results

This study included a total of 47 patients who were confirmed to hav confirmed to have ETG. Among them, we found 29 cases of accessory thyroid and 18 cases of aberrant thyroid. Furthermore, 42 cases exhibited the single ETG, while 5 cases displayed the double ETG. The distribution of the ETG was as follows: 20 were lingual, 10 were submandibular, 10 were lateral cervical, 4 were thoracic mediastinal, 1 was esophageal, and 7 were ovarian. Of these cases, 22 patients underwent surgery, 18 received thyroid hormone replacement therapy, and 7 were placed under observation. All patients were followed up for 59.4 (12-117) months. No significant abnormalities were detected at the conclusion of the follow-up period.

Conclusion

ETG is frequently observed in the head and neck, particularly in lingual. Accessory thyroid glands are commonly reported, with most cases being single ETG. Notably, these glands usually do not manifest specific clinical symptoms. Therefore, the appropriate and comprehensive examinations during the initial diagnosis are crucial to avoid misdiagnosis. Treatment should be individualized, and long-term follow-up is essential for managing ETG effectively.

An unusual ectopic thyroid tissue location & review of literature

Ectopic thyroid is well-known pathology for several decades. Many locations have been described. Nowadays, only three cases of skull base location have been described in literature. In our case, we reported a single case of a 39-year-old male presenting with a supra-sellar and suprachiasmatic location. He presented no clinical symptoms, no endocrine alteration on biology and no skull base invasion which make this case unique compared to actual literature. Such diagnosis should always be an exclusion diagnosis as secondary neoplastic should be first ruled out.

Ectopic thyroid tissue in the breast: A case report

Ectopic thyroid tissue is a rare condition manifested as the appearance of thyroid tissue outside the thyroid gland. Here, we report a case of ectopic thyroid tissue in the breast. A 48-year-old Chinese woman who was diagnosed with breast cancer received modified radical mastectomy. A thyroid tissue was found on subsequent pathological examination. The ectopic thyroid tissue was confirmed by immunohistochemistry staining of thyroid biomarkers, including thyroglobulin, thyroid transcription factor-1, and thyroid peroxidase. Currently, abnormal thyroid anlage descent is the main theory to explain ectopic thyroid tissue, especially lingual thyroid. However, it is far-fetched to explain the pathogenesis of ectopic thyroid tissues existed in organs or tissues far from thyroid such as iris, cardiac, pulmonary, duodenal, adrenal, and vertebral. Here, we reviewed the previous cases of ectopic thyroid tissue in breast and proposed a "entoderm migration" theory to explain distant ectopic thyroid tissues based on embryonic development perspective.

Imaging Features of Ectopic Tissues and Their Complications: Embryologic and Anatomic Approach

Ectopic tissue is an anatomic abnormality in which tissue develops in an area outside its normal location. It is primarily caused by abnormalities during the process of embryologic development. Although the majority of individuals with ectopic tissues remain asymptomatic, various symptoms and associated complications can occur. Failure in normal embryologic development leads to loss of normal physiologic function or may result in harmful functions such as ectopic hormonal secretion in the ectopic pituitary adenoma. Ectopic tissues may also frequently mimic tumors. For example, developmental abnormalities in the pharyngeal pouches may result in an ectopic parathyroid gland and ectopic thymus, both of which are frequently misdiagnosed as tumors. Adequate knowledge of embryology is essential for understanding the differential diagnoses of ectopic tissues and facilitating appropriate management. The authors summarize the embryologic development and pathogenesis of ectopic tissues by using illustrations to facilitate a deeper understanding of embryologic development and anatomy. Characteristic imaging findings (US, CT, MRI, and scintigraphy) are described for ectopic tissues of the brain, head, neck, thorax, abdomen, and pelvis by focusing on common conditions that radiologists may encounter in daily practice and their differential diagnoses. ^©RSNA, 2023 Quiz questions for this article are available through the Online Learning Center.

Ectopic intrapulmonary thyroid masquerading as metastatic carcinoma of the lung: a rare case scenario

BACKGROUND

The intrapulmonary ectopic thyroid gland is exceedingly rare since the ectopic thyroid was discovered. Only eight cases have been reported in the worldwide literature. We present a case of multiple intrapulmonary ectopic thyroid glands with nodular goiter in a 10-year-old girl.

CASE PRESENTATION

The girl was found with multiple intrapulmonary nodules in bilateral lungs during the treatment of nodular goiter. The intrapulmonary lesions were initially thought to be a high possibility of metastatic cancer. A computed tomography-guided percutaneous lung biopsy was performed, and the pathological examination confirmed that the diagnosis was ectopic intrapulmonary thyroid.

CONCLUSION

The ectopic intrapulmonary thyroid should be considered when children with nodular goiter presenting with suspected metastases in the lung.

Mediastinal papillary thyroid carcinoma treated by video-assisted thoracic surgery - Case report

INTRODUCTION AND IMPORTANCE

The mediastinal ectopic thyroid gland is rare and usually asymptomatic. Ectopic thyroid tissue has malignant potential, but ectopic thyroid cancers are extremely rare, particularly mediastinal thyroid cancer, with only five cases reported in the literature.

CASE PRESENTATION

A 73 years-old male patient diagnosed with multinodular goitre with two FLUS cytology was summited to an uneventful total thyroidectomy. Pathology revealed 8 synchronous papillary carcinomas in both thyroid lobes. Follow-up identified persistent elevation of thyroglobulin. A cervical ultrasound and cervical and thoracic CT scan were performed, identifying a mediastinal tumour of 6 × 3 cm. Resection was performed by video-assisted thoracic surgery (VATS). Pathology identified an ectopic mediastinal thyroid with a 4 mm papillary microcarcinoma. Recovery was uneventful and the patient is currently asymptomatic.

CLINICAL DISCUSSION

There is no consensus on the best treatment strategy for mediastinal ectopic thyroid, but surgical resection is advised as being the only method allowing for a complete cure. Although both thoracotomy and sternotomy approaches have been usually used for mediastinal thyroid tumours resection, the thoracoscopic approach has been used with good results in recent years. Thoracoscopy has better visualization, less morbimortality, and faster recovery. Giant masses (>10 cm) are the only limitation for VATS.

CONCLUSION

Ectopic mediastinal thyroid is extremely rare, and its malignant transformation is even rarer. There is no consensus on the best treatment strategy, but surgical resection of the mediastinal thyroid is advised. VATS is a safe and feasible minimally invasive technique with good outcomes.

Tongue Base Ectopic Thyroid Tissue-Is It a Rare Encounter?

Failure in the embryological development of the thyroid in adults is rarely seen. We present the case of a 79-year-old female patient who complained of dysphagia and progressive upper respiratory obstruction, which started 12 months prior to her admission. An ENT clinical exam revealed a tongue base, spherical, well-defined tumour covered by normal mucosa. Further assessments established the diagnosis of the tongue base ectopic thyroid tissue. Due to the patient's symptoms, a transhyoid tongue base tumour removal was performed. The selected patient gave consent for participation and inclusion in this paper, in compliance with the 1964 Helsinki declaration.

Paraganglioma of the anterior superior mediastinum: Presentation of a case of mistaken diagnosis so long and review of the literature

INTRODUCTION AND IMPORTANCE

Mediastinal paraganglioma is a rare tumor with neuroendocrine activity, highly susceptible to misdiagnosis. Herein, we present a case misdiagnosed as Castleman disease for nearly a decade, significantly enlarged, lost the opportunity of thoracoscopic surgery, and was removed by median thoracotomy.

CASE PRESENTATION

A 59-year-old woman complained of having a mediastinal mass, was diagnosed with Castleman disease for nearly a decade and was admitted to the hospital due to neck tightness. The tumor size was significantly enlarged. We proceeded to interventional angiography with gelatin sponge angioembolization, and the tumor was resected through a median sternotomy on the second day. The operation was smooth, and the tumor was gray and slightly brittle. Postoperative pathology confirmed paraganglioma; lymph node metastasis was not detected (0/3).

CLINICAL DISCUSSION

Mediastinal paraganglioma is a rare tumor and can be either functional or nonfunctional. It can be differentiated from many diseases. The SSTR-PET-CT labeled with 68Ga-somatostatin analog, plasma metanephrine, and normetanephrine are essential for the diagnosis. Surgical resection is the most effective form of treatment. Pre-operative embolization of the feeding artery is considered to have a low rate of intraoperative bleeding. We recommend making comprehensive preparations to ensure perioperative safety and long-term survival.

CONCLUSION

When a vascularized mass is discovered in the mediastinum, surgeons should consider the possibility of a paraganglioma. Multidisciplinary consultation should be involved in the formulation of treatment plans. Lifelong surveillance for residual tumor growth and recurrence is required.

An Interesting Case of Thyrotoxicosis

Ectopic thyroid tissue can be present in the embryonal path of descent of the thyroglossal duct anywhere from the foramen caecum to the thyroid gland. However, for such ectopic thyroid tissue to be hyperfunctioning is quite rare. Here, we discuss a 56-year-old female patient who presented with persistent thyrotoxicosis for over 7 years. She had undergone thyroidectomy in 1982 for thyrotoxicosis and was rendered hypothyroid (thyroid-stimulating hormone of 75 μIU/mL). Whole-body technetium scan was done twice which did not show any uptake in the neck or other parts of the body and an empirical dose of 15 mCi of radioiodine therapy was also given to treat the thyrotoxicosis. She continued to be thyrotoxic and was on carbimazole 30 mg/day along with beta-blockers. In 2021, an Iodine131 whole-body scan revealed small remnant thyroid tissue and an ectopic thyroid tissue in a thyroglossal cyst. In such cases of persistent or recurrent thyrotoxicosis despite standard treatments, an ectopic location should be sought after and treated.

Diferansiye tiroit karsinomlu olgularda nadir bir tanısal yanılgı sebebi: Lateral servikal ektopik tiroit

Ektopik tiroit genellikle boyun orta hatta izlenmekle birlikte, nadir olarak lateral yerleşimli de olabilir. Bu çalışmada diferansiye tiroit karsinomu nedeniyle total tiroidektomi uygulanan ve lateral ektopik tiroit dokusu saptanan 4 olgu sunulmaktadır. Operasyon sonrası evreleme için Tc99m perteknetat ile yapılan sintigrafi incelemesinde olguların 3’ünde submandibuler bölgede artmış tutulum izlenen alanda, ultrasonografik incelemede tiroit bezi ile eş ekojenite homojen iç yapıda ektopik tiroit dokusu saptanırken, diğer olguda alt juguler bölgede izlenen heterojen iç yapıda nodüler lezyon, yapılan santral-lateral boyun diseksiyonu sonucunda ektopik tiroit dokusu tanısı almıştır. Metastatik lenf bezi ile primer lateral ektopik tiroit dokusu ayrımı primer tiroit karsinomlu olgularda oldukça önemli olup, laboratuvar verileri, sintigrafi ve ultrasonografiyi içeren tanısal çalışma evrelemede kritik rol oynamaktadır. Oldukça nadir olmakla birlikte ektopik tiroit, lateral boyun kitlelerinin ayırıcı tanısında akılda bulundurulmalıdır.

Case report: surgical management of symptomatic pretracheal thyroid gland in a patient with dual ectopic thyroid

BACKGROUND

Dual ectopic thyroid, a very rare condition, is defined as the simultaneous presence of ectopic thyroid tissue in two abnormal locations. Here, we report the surgical management of a patient with dual ectopic thyroid.

CASE PRESENTATION

The patient was a 12-year-old boy with right para-midline swelling for 2 months. On physical examination of the upper anterior neck, there was a 4 cm × 3 cm mass that was soft, mobile, smooth, and painless. Blood examination showed euthyroidism. Neck ultrasonography showed a well-circumscribed multilocular cyst. We followed up by observation only because the patient had no local symptoms or malignancy. After 2 years, the mass gradually enlarged, so we performed surgery to improve cosmetic outcomes. Preoperative neck CT revealed both a high-density solid mass at the base of the tongue and a central low-density region surrounded by a high-density area at the pretracheal region below the hyoid. The infrahyoid mass was surgically removed, and the sublingual mass was left intact. Pathological findings showed the growth of multiple-size follicles, leading to a diagnosis of adenomatous goiter. Postoperative 123-I scintigraphy showed radioactive iodine uptake in the sublingual lesion, but none in the normal thyroid bed despite the extirpation of thyroid tissue. Postoperative thyroid hormone replacement was started for subclinical hypothyroidism. One year postoperatively, the patient became euthyroid.

CONCLUSION

Surgical excision was used to manage a symptomatic cervical infrahyoid mass related to dual ectopic thyroid. Postoperatively, thyroid hormone replacement was required both to prevent enlargement of the remaining sublingual thyroid and to maintain adequate thyroid hormone levels.

Management of Lingual Thyroid with Second Thyroid Anomaly: An Institutional Experience

Patients diagnosed with Lingual thyroid (LT) may have second thyroid anomaly (STA).Given rarity of dual ectopics/anomalies, standardized management recommendations are lacking. We aimed to describe our experience in management of LT with STA and suggest a management algorithm. We conducted a retrospectivechart review of patients diagnosed with LT between Jul-2013 and Dec-2019. Data regarding demographics, clinical presentation, endocrine-profile, associated STA treatment received, and outcomes were collected and analyzed. Eight patients (female-7 cases, male-1 case, adult-4 cases, children-4 cases, mean age-18.1 years, range 6-43 years) with LT were identified. Four(50%) cases had STA in addition to LT (thyroglossal cyst in two-cases, sublingual thyroid in one-case and sub-mental thyroid in one-case) and presented as neck mass. Diagnosis was confirmed with flexible-nasopharyngoscopy,ultrasonography,thyroid-scintigraphy and computed-tomography. Ectopic thyroid(s) was/were only functional thyroid gland with absence of normal thyroid in all cases. Two- cases had symptomatic for LT and were managed by coblation assisted excision of LT in one and I131 ablation in one-case.All adult patients were hypothyroidand received thyroxin.All pediatric cases were euthyroidand received no surgical intervention for LT.Three patients required surgery for STA; Sistrunk surgery in two and excision of submental thyroid in one. All cases were asymptomatic. These results were utilized to suggest a management algorithm for LT with STA. LT patients with STA are more symptomatic and required more surgical interventions in compare to isolated LT. When appropriate, excision of STA with/without intervention for LT and thyroxin is advocated as the treatment modality of choice in LT patients with STA.

Diagnosis and treatment of ectopic thyroid carcinoma: A case report and literature review

INTRODUCTION

Ectopic thyroid cancer (ETC) is primary thyroid cancer occurring in ectopic thyroid tissue, and its incidence rate is approximately 0.3%-0.5% of thyroid cancer. Only approximately 132 cases of ETC have been diagnosed and treated worldwide in the past 110 years, with most of them being adults. Of note, patients with ETC are prone to misdiagnosis and mistreatment.

CASE REPORT

This was a 13-year-old adolescent female who reported having a sensation of swallowing obstruction when eating blocky foods. Color Doppler Ultrasound (CDU) found a 2.3 cm ×1.7 cm × 2.1 cm hypoechoic nodule slightly to the right of the deep surface of the tongue base, with a honeycomb shape. Meanwhile, a mixed echogenic nodule of approximately 2.0 cm × 1.9 cm × 2.3 cm was seen deep in the mouth floor, and a very low echogenic region of 1.4 cm × 1.1 cm × 1.8 cm was observed in the nodule. We then performed a fine needle aspiration biopsy (FNAB) of the thyroid nodules guided by CDU, and the results showed papillary thyroid carcinoma (PTC). Then, a local extended resection of the thyroid carcinoma was performed. Bilateral cervical IA and adjacent subhyoid lymph node dissection was performed through a small anterior cervical incision. The patient recovered well, and was discharged on the fifth day after surgery. The patient only took levothyroxine tablets for replacement therapy after surgery. The patient was followed up for 36 months, and the thyroid function remained in the normal range. Reexamination by CDU showed no tumor recurrence, lymph node enlargement, or obvious change in the tongue base ectopic thyroid.

CONCLUSIONS

ETC is an extremely rare type of thyroid cancer, which is easy to be misdiagnosed. Preoperative use of CDU, nuclide scanning, computed tomography (CT)/Magnetic resonance imaging (MRI), and FNAB can significantly reduce the misdiagnosis rate of this disease. Surgery is currently the main treatment for ETC. Complete resection still has a high cure rate. For patients with advanced ETC who cannot be completely resected, external radiotherapy and targeted therapy can be tried, but the prognosis needs to be verified with more cases in the future.

Thyroid scintigraphy and hybrid SPECT/CT in a rare case of dual ectopic thyroid

Dual ectopic thyroid (DET) is a rare disorder occurring as a result of aberrant embryonic development characterized by simultaneous presence of thyroid tissue at two ectopic sites. 99mTc-Pertechnetate thyroid scintigraphy remains gold standard in confirming ectopic thyroid tissue. This case highlights the importance of thyroid scintigraphy and Single Photon Emission Computed Tomography with Computed Tomography (SPECT/CT) in evaluation of ectopic thyroid tissue and DET that manifested itself during patients' pregnancy.

Rare ectopic thyroid tissue as multiple bilateral pulmonary nodules: a case report and literature review

Background

The prevalence of ectopic thyroid tissue is 1 in every 100,000 to 300,000 persons in the general population, and ectopic thyroid tissue in the bilateral lung lobes is even rarer. Due to its rarity, there is no definitive or standard guidance on the diagnosis and treatment of ectopic thyroid tissue presenting as multiple bilateral pulmonary nodules.

Case presentation

A 56-year-old woman presented with multiple bilateral pulmonary nodules, and the patient had a history of hyperthyroidism but had no symptoms of ectopic thyroid tissue. Computed tomography (CT) demonstrated multiple solid nodules in both lungs, and the largest nodule (sized 15 × 14 mm) was located in segment 5 of the upper left lung. The initial diagnosis based on imaging was metastatic malignancies. Positron emission tomography-computed tomography (PET-CT) showed multiple bilateral intrapulmonary nodules that had slightly increased metabolism (SUVmax 1.7). The largest pulmonary nodule and another nodule in the left lung were resected by video-assisted thoracoscopy surgery (VATS). The pathological and immunohistochemical (IHC) examinations confirmed a diagnosis of ectopic thyroid tissue. No postoperative adjuvant therapy was given, and the patient was discharged 3 days after the operation and had regular follow-up examinations.

Conclusion

The diagnosis of ectopic thyroid tissue in the bilateral lung lobes is extremely difficult and should be considered carefully. PET-CT and surgical resection of intrapulmonary nodules are alternatives for clinicians in diagnosing ectopic thyroid tissue. Regular postoperative follow-up is needed.

Ectopic thyroid carcinoma in the mandible with normally located goiterous thyroid gland: A case report

BACKGROUND

The presence of ectopic thyroid tissue is a developmental disorder that affects about one per 100,000-300,000 people. It is extraordinarily rare for ectopic thyroid to be out of the lines of its descent. This case is the first to report a cancerous ectopic thyroid in the mandibular bone with a goitrous orthotopic thyroid gland.

CASE PRESENTATION

80-year-old female of free medical background presented to our clinic with painless left mandibular swelling that recent increase in size after tooth extraction. Surprisingly the diagnosis of ectopic thyroid tissue with cancerous follicular cells was reached upon histological analysis. The goitrous thyroid gland was found in its expected cervical location, and the patient was euthyroid.

CONCLUSION

Because this diagnosis extremely rare, the possibility of ectopic thyroid carcinoma in cases of a pathological mass in the mandible must always be carefully thought out. A high degree of suspicion is essential as the unusual presentation could take.

Does surgical management still play a role in the management of ectopic lingual thyroid: Institutional experience and systematic review of the literature

OBJECTIVE

Management of ectopic lingual thyroid (ELT) must balance the morbidity of disease with the morbidity of treatment. We investigate clinical outcomes associated with modern treatment options and analyze the role of transoral surgery in the treatment algorithm for ELT.

METHODS

This was a retrospective chart review of ELT patients treated at a tertiary care center from 1/1/1979 to 12/31/2019. In addition, a systematic review of the literature from 1979 to 2021 for reports of ELT was performed. Symptoms defined as high-risk were dysphagia, dysphonia, dyspnea, neck swelling, bleeding, and obstructive sleep apnea (OSA).

RESULTS

36 patients within the institutional cohort (IC) and 224 cases in the systematic review (SRC) met criteria. The most common presenting symptoms for both cohorts were dysphagia, globus sensation, and dysphonia. One third of each cohort were hypothyroid, while 3% (n = 1) and 9% (n = 21) of the IC and SRC, respectively, had clinical suspicion of malignancy at presentation. 27% (n = 10) of the IC and 55% (n = 121) of the SRC underwent surgical therapy. There was a 4% (3/72) transoral bleed rate for all patients undergoing transoral surgery. Other reported complications were minor. There were no tracheostomies, and no deaths. Among observed, medically treated, and surgically treated patients, symptoms improved during follow up for 43% or 68% in the IC and SRC, respectively. Following surgery, symptoms improved or resolved for 86% or 93% in the IC and SRC, respectively.

CONCLUSIONS

Asymptomatic ELTs with no concern for malignancy can be managed with observation. Patients with mild symptoms or hypothyroidism may trial thyroid suppressive therapy or RAI. RAI can be considered for patients with high-risk symptoms. For patients with symptoms resistant to conservative therapy, concern for malignancy or high-risk symptoms not conducive to RAI, surgery should be considered. Transoral approaches offer acceptable morbidity, and most patients experience resolution of symptoms following this approach.

[Ectopic thyroid carcinoma in front of hyoid bone misdiagnosed as thyroglossal cyst：a case report]

A clinical case of ectopic thyroid carcinoma in front of hyoid bone was reported in this paper. The patient, a 17-year-old female, presented with an enlarging neck mass of 1-week history. Physical examination revealed a 3 cm×2 cm neck mass in front of the hyoid bone. Ultrasonographic depicted as a cystic solid mixed echogenic mass with punctate strong echogenicity. CT scan showed a cystic-solid mass in front of the hyoid bone with punctate calcifications. The patient was misdiagnosed as a thyroglossal duct cyst and underwent surgery. The final pathological diagnosis was papillary thyroid carcinoma with cyst formation.

Airway management in patients with lingual thyroid: a case report and review of the literature

PURPOSE

To review the management of patients with lingual thyroid (LT) causing upper airway obstruction and to suggest a diagnostic and therapeutic workflow.

METHODS

A PubMed review of published cases from January 1980 up to December 2020 of LT causing upper airway obstruction. We selected cases of confirmed LTs that presented with non-state-dependent airway obstruction. An illustrative case report is presented.

RESULTS

Twenty-one articles fulfilling the inclusion criteria were found, reporting 24 cases (7 neonatal, 2 pediatric and 15 adults). The main presenting symptoms was dyspnea with increased work of breathing, followed by dysphagia and stridor most commonly in neonates. At least one imaging modality was performed in all patients. Thyroid function was altered in half the patients and normal in the other half. The LT was the only thyroid tissue in all cases except 2. Altogether, 5/24 patients required tracheostomies and two-thirds of the patients underwent surgical resection of the LT (mostly transoral). Also 2/3 of the patients received thyroid replacement therapy. After a median follow-up of 17 months, airway symptoms had fully resolved for all patients but one.

CONCLUSION

While rare, ectopic LTs should be considered in the differential diagnosis of stridor, dyspnea and airway obstruction. In neonates, concomitant presence of hypothyroidism on neonatal screening and airway obstruction should prompt the search for a LT. Early identification and thyroid replacement therapy seem to significantly relieve symptoms of upper airway obstruction, but severe obstruction and concomitant airway lesions may require more definitive management approaches.

Benign Ectopic Thyroid in the Lateral (Level II) Neck Compartment

Ectopic thyroid most commonly presents in the midline and is typically associated with the absence of an orthotopic thyroid. Less commonly, ectopic thyroid can present in the lateral neck, typically with a coexisting orthotopic thyroid and abnormal pathology in either the ectopic or orthotopic thyroid tissue. This paper describes a rare case of a benign, ectopic thyroid in the lateral neck (level II) associated with a normal, benign orthotopic thyroid. This report illustrates clinical pearls for the management of this unusual entity.

Ectopic thyroid nodes in the mediastinum - report of two cases

Introduction. Ectopic thyroid is rare anomaly characterized by presence of thyroid tissue outside its normal location, which could be the consequence of developmental abnormality, sequestration of thyroid nodes from nodal thyroid goiter or mechanical implantation of thyroid tissue after resection or trauma. Ectopic thyroid commonly is incidentally detected and causes differential diagnostic dilemma towards the neck and mediastinal tumors. The object of this report was to present two types of ectopic thyroid nodes located in the upper mediastinum those were incidentally discovered by computed tomography (CT). Outline of cases. In a 42-year-old woman with the adenocarcinoma of esophagogastric junction in whom CT was performed due to staging purposes, a hyper dense nodular lesion was found in the anterior upper mediastinum. Metastatic left supraclavicular lymph node was considered in the differential diagnosis. However, as node was located in front of the neck fascia and just below the thyroid gland and showed similar density to thyroid tissue, the diagnosis of accessory thyroid gland was made, which was later confirmed by multiple repeated CT scans during the two-year follow-up period. In a 52-year-old woman who was presented with intermittent chest pain and cough, contrast-enhanced CT scan revealed nodal thyroid goiter and three nodes of similar CT texture, located in the upper mediastinum, below the thyroid gland. Accordingly, the diagnosis of parasitic mediastinal goiter thyroid nodes was made. Conclusion. Ectopic thyroid nodes are presented by CT as well-circumscribed nodes of same density as the thyroid gland, typically located anteriorly in the upper mediastinum.

Ectopic Pulmonary Goiter Simulating Malignant Tumor Detected on SPECT/CT

ABSTRACT

A 46-year-old asymptomatic woman with a newly detected large pulmonary mass was admitted to our hospital. An ultrasonography-guided needle biopsy was performed based on a suspicion of malignancy, and an ectopic goiter was confirmed pathologically. Laboratory findings were unremarkable, except that thyroid function tests suggested subclinical hyperthyroidism. A 131I whole-body scintigraphy and SPECT/CT were further performed and revealed intense radioiodine uptake in the pulmonary mass, the mediastinal nodule, and thyroid gland. A diagnosis of ectopic pulmonary goiter with normally located thyroid was finally made.

Distinguishing between isthmic thyroglossal duct cyst and goitre on nuclear thyroid scan: A case report

Thyroglossal duct cysts, which are the most frequently encountered congenital cervical anomalies in children, occur due to embryologic remnants of the thyroglossal duct. Although diagnosis may be challenging, clinicians can be aided by imaging and fine-needle aspiration biopsies. We describe the clinical management of a two-year-old boy with a thyroglossal duct cyst mimicking a goitre on a pertechnetate thyroid scan.

Ectopic Mediastinal and Lumbar Thyroid Tissue

The thyroid gland is found in the neck and corresponds to the 2-4 tracheal cartilages. It is rarely found in other sites and is termed ectopic thyroid tissue (ETT) once found. In this report, we present a case of a 19-year-old female who was diagnosed with ETT in the lumbar region and posterior mediastinal region after total thyroidectomy for a large dominant thyroid nodule. ETT has a unique presentation and physicians should be vigilant to diagnose it correctly and promptly to decrease morbidity associated with the disease.

Ectopic thyroid tissue in the anterior mediastinum along with a normally located gland

Ectopic thyroid tissue is a rare developmental abnormality arising from an aberration in the normal migration of the thyroid gland, from the floor of the primitive foregut to its final position. It is usually asymptomatic, often being diagnosed as an incidental finding. However, it can present with symptoms of compression such as chest pain, cough, stridor, dysphagia, dyspnea and superior vena cava syndrome. Herein, we present the case of a 42-year-old male patient, presenting with dyspnea, chest pain and fatigue. Laboratory tests showed low serum levels of thyroid-stimulating hormone (TSH) and a thoracic computed tomography revealed a heterogeneous mass in the anterior mediastinum. The patient underwent a full surgical resection. The postoperative histopathological examination of the mass demonstrated the presence of benign ectopic thyroid tissue with no evidence of malignancy. This case report emphasizes the importance of taking Ectopic thyroid tissue into account when considering the differential diagnosis of a mediastinal mass, as other common diagnoses including lymphomas, dermoid cysts and thymic tumors, require an entirely distinct treatment approach.

Lingual thyroid with severe hypothyroidism: A case report

INTRODUCTION

Ectopic thyroid tissue presenting at the base of the tongue, called lingual thyroid, is a clinical rarity. Clinical presentation varies depending upon either the severity of regional symptoms associated with the enlargement of gland size, or the features related to thyroid dysfunction.

PATIENT CONCERNS

We reported a case of a 29-year-old female who presented with symptoms of easy fatigue and depression for 3 months.

DIAGNOSIS

After a series of diagnostic workup, the lingual thyroid with severe hypothyroidism was diagnosed.

INTERVENTION AND OUTCOME

She received conservative treatment with thyroid hormone replacement and the symptoms improved significantly.

LESSONS

Lingual thyroid is a rare entity that needs careful diagnostic workup including clinical examination, biochemical tests, imaging methods such as ultrasonography, scintigraphy, computed tomography, magnetic resonance imaging, and fine-needle aspiration cytology to plan the management. Lingual thyroid with hypothyroidism and no neck regional symptoms can be conservatively treated and requires regular follow-up for the prevention of potential risk of malignant transformation.

Case of Colloid Nodular Goitre in a Rare Submandibular Location

Ectopic thyroid gland occurs due to aberrant descent of primitive thyroid gland to the final pre-tracheal position and failure of fusion of thyroid anlages. Submandibular ectopic thyroid is a rare thyroid anomaly that can present with or without an orthotopic thyroid gland. We present a case of a young female with hypothyroidism and left submandibular swelling demonstrated to be an ectopic thyroid with the colloid nodular goitre on imaging and cytology.

Hypothyroidism following sistrunk procedure: Thyroglossal duct cyst or ectopic thyroid?

Thyroglossal duct cyst is the most common cause of anterior midline neck swelling in children, but ectopic thyroid is an important but rare differential diagnosis. Establishing the orthotopic thyroid gland status is crucial as inadvertent removal of a lone functioning ectopic thyroid tissue in young children could lead to fluttering of growth and development if not identified early. We report the case of a 2 years 10-month-old boy who had Sistrunk's procedure for 'thyroglossal duct cyst': Diagnosed using USS, defaulted follow-up and presented subsequently with growth retardation from hypothyroidism.

Mediastinal ectopic thyroid tissue, an imitator of an enlarged lymph node with metastatic pulmonary neoplasia

The prevalence of ectopic thyroid tissue, based on autopsy studies, is between 7% and 10%, but there are rare cases reported in the thoracic region. Here, we encountered a case of thoracic ectopic thyroid tissue presenting as a presumed enlarged mediastinal lymph node. A 50-year-old female with a history of lung adenocarcinoma, status post resection, presented with complaints of headache, dizziness, and nausea. Magnetic resonance imaging found two brain lesions consistent with metastasis. Computed tomography scan showed enlarged mediastinal lymph nodes and thyroid nodules. Fine-needle aspiration (FNA) of one thyroid nodule was positive for papillary thyroid carcinoma. FNA of the mediastinal lymph nodes were negative for metastatic carcinoma but revealed thyroid tissue in the 2.9 × 1.6 cm presumed 2 L lymph node. The morphological features and immunohistochemical stains confirmed thyroid tissue, and there were no cytological features of thyroid carcinoma. In patients with a history of a pulmonary tumor (such as adenocarcinoma, low-grade neuroendocrine tumor), ectopic thyroid tissue, although a rare event, could represent a pitfall in the cytologic evaluation of mediastinal lymph nodes aspirates obtained from staging procedures. Careful morphologic examination with a panel of immunohistochemical studies are useful in making the correct diagnosis, leading to appropriate patient management.

Graves' disease and recurrence in ectopic thyroid tissue after total thyroidectomy

We report a case of a 46-year-old woman who presented with a midline neck mass 2 years after total thyroidectomy for Graves' disease. Despite levothyroxine treatment withdrawal, she remained biochemically with subclinical hyperthyroidism. Her thyroid stimulating hormone receptor antibodies were consistently elevated. Neck ultrasonography revealed an infrahyoid solid nodule and pertechnetate scintigraphy confirmed an increased uptake at the same level, without any uptake in the thyroid bed. Treatment with methimazole 5 mg/day was initiated with clinical improvement and achievement of euthyroidism. After that, she received 10 mCi of radioactive iodine. Since then, she experienced regression of the neck mass and is doing well on a replacement dose of levothyroxine. Recurrence of Graves' disease in ectopic thyroid following total thyroidectomy is extremely rare. This diagnose should be considered in patients who underwent total thyroidectomy and remained with thyrotoxicosis despite decreasing the levothyroxine dose.

Causes of False-Positive Radioactive Iodine Uptake in Patients with Differentiated Thyroid Cancer

Purpose

Radioactive iodine (RAI) whole-body scan is a sensitive imaging modality routinely used in patients with differentiated thyroid cancer to detect persistent and recurrent disease. However, there can be false-positive RAI uptake that can lead to misdiagnosis and misclassification of a patient’s cancer stage. Recognizing the causes of false positivity can avoid unnecessary testing and treatment as well as emotional stress. In this review, we discuss causes and summarize various mechanisms for false-positive uptake.

Recent Findings

We report a patient with differentiated thyroid cancer who was found to have Mycobacterium avium complex infection as the cause of false-positive RAI uptake in the lungs. Using this case example, we discuss and summarize findings from the literature on etiologies of false-positive RAI uptake. We also supplement additional original images illustrating other examples of false RAI uptake.

Summary

False-positive RAI uptake may arise from different causes and RAI scans need to be interpreted in the context of the patient’s history and corresponding cross-sectional imaging findings on workup. Understanding the potential pitfalls of the RAI scan and the mechanisms underlying false uptake are vital in the care of patients with differentiated thyroid cancer.

Radiological insights of ectopic thyroid in the porta hepatis: A case report and review of the literature

BACKGROUND

Ectopic thyroid is defined as a rare developmental anomaly where thyroid tissues are atypically found in locations other than its normal anatomical position: Anterolateral to the second, third, and fourth tracheal cartilages. An intemperate descent or a migration failure of the thyroid anlage results in sub-diaphragmatic thyroid ectopia, a sparse clinical entity.

CASE SUMMARY

This case portrays a 63-year-old female patient presenting with chronic abdominal discomfort at a local hospital whereby a computed tomography (CT) scan revealed a well-defined mass in the hepatic entrance. For further examination, the patient underwent a CT scan with contrast, magnetic resonance imaging (MRI), and CT-angiography (CTA) at our department. The CT scan showed a well-defined and high attenuated mass measuring 43 mm × 38 mm in the hepatic entrance with calcification. The CTA revealed an additional finding: Blood supply to the mass from the right hepatic artery. MRI of the upper abdomen demonstrated a mass with mixed signal intensity on T1 and T2 weighted images in the hepatic entrance. The patient underwent surgery with resection of the mass which was sent for histopathology. Ectopic thyroid at the level of porta hepatis with nodules was the definitive diagnosis since histopathological report revealed presence of thyroid tissue in the resected liver mass.

CONCLUSION

This case delivers a rare insight of pre-operative radiological imaging of an ectopic thyroid located in the liver. These findings can aid in narrowing down potential differential diagnosis when managing a patient with those subsequent findings.

Adenomatous hyperplastic intratracheal ectopic thyroid tissue: a case report

Intratracheal ectopic thyroid (ITET) is a rare disease, with limited cases reported in the literature. ITET is an unusual congenital abnormality and can be easily mistaken for a respiratory illness. We present a case of a 61-year-old man with a history of slight discontinuous hemoptysis for 2 years. A tracheal mass, which appeared to be connected to the left thyroid gland, was found by chest computed tomography scan. Ultrasound revealed one suspiciously malignant, solid and hypoechoic nodule in the left thyroid gland. After the thyroid origin of the mass was confirmed by bronchoscopic biopsy, the patient underwent segmental resection and anastomosis of the trachea, together with left thyroidectomy. Histopathology of the tracheal tumor showed adenomatous hyperplastic ITET, and the orthotopic left thyroid gland showed nodular goiter with atypical adenomatous hyperplasia. Clinical suspicion is warranted in patients presenting with a tracheal tumor seemingly connected to the thyroid gland, particularly in patients who have imaging features suggestive of a malignant tumor in the orthotopic thyroid but without confirmative histopathology of malignancy before surgery.

Massive lateral neck mass: aberrant ectopic thyroid malignancy

Lateral aberrant ectopic thyroid is very rare, comprising only 1%-3% of all the ectopic thyroid tissue. Clinically, these lesions are mistaken for lymph node swelling or metastatic tumour. Primary carcinoma in lateral aberrant ectopic thyroid with normal active native thyroid is very uncommon. We report a case of papillary carcinoma in lateral aberrant ectopic thyroid tissue, with a completely normal native thyroid gland in a 53-year-old man, who presented with a massive swelling in the lateral aspect of the neck clinically and radiologically diagnosed as a malignant soft tissue tumour with differential diagnosis of malignant lymphoma. Fine needle aspiration cytology revealed metastatic papillary carcinoma. In toto excision of the soft tissue mass along with subtotal thyroidectomy was performed. Histology of the mass revealed papillary carcinoma of lateral aberrant ectopic thyroid, while the thyroid gland did not show evidence of malignancy. The postsurgical period was uneventful, and the patient underwent radioiodine ablation.