Colloid nodular goitre associated with hemiagenesis of the thyroid gland.

Hemiagenesis of the thyroid gland is a rare congenital abnormality usually left unnoticed without associated thyroid disorders. The most common congenital anomaly of the thyroid gland is a thyroglossal cyst, followed by ectopic thyroid tissue and thyroid dysgenesis, which may be agenesis or hemiagenesis. Preoperative underevaluation of the thyroid hemiagenesis (THA) associated with other thyroid disorders may cause intraoperative difficulty in identifying the gland and difficulty in preservation or even identification of major neurovascular structures during neck exploration. We report a patient who presented to us with right-sided neck swelling. On further evaluation and neck exploration, the patient was diagnosed with THA of the left lobe with right colloid goitre.

Parapharyngeal space ectopic thyroid with eutopic papillary thyroid cancer: A case report.

BACKGROUND: Ectopic thyroid is a rare condition. Here we report an extremely rare case of parapharyngeal space ectopic thyroid, which has simultaneously found the papillary thyroid carcinoma of the eutopic thyroid. CASE PRESENTATION: A 54-year-old woman was admitted to our hospital for a thyroid tumor and neck lymph nodes. CT and MR imaging revealed the presence of a thyroid right node, as well as a right parapharyngeal mass with a diameter of 2.5 × 2.3 cm. PET-CT was also performed to diagnose further, revealing that the suv metric of the PPS mass was 4.03. Considering that the mass was asymptomatic, we did not handle it at the first thyroid surgery. However, when the patient underwent a radioactive iodine scan before the radioactive iodine treatment, the imaging showed that the mass could intake the iodine. So, we arranged the second surgery for this mass, and the postoperative pathological examination confirmed the mass was well-differentiated thyroid tissue. CONCLUSION: Parapharyngeal ectopic thyroid with eutopic thyroid cancer is extremely rare. Preoperative imaging examination can significantly avoid the missed diagnosis of this disease. Surgical resection is recommended for the ectopic thyroid while the eutopic thyroid is found to be malignant.

Robotic Resection of Ectopic Thyroid Tissue of the Mediastinum - Case Report and Literature Review.

Introduction: Ectopic thyroid tissue (ETT) is a rare cause of mediastinal masses, representing less than 1% of all mediastinal tumors (1). ETT could be detected anywhere along the path of the first embryonic descent of the thyroid gland from the primordial foregut floor to its usual pre-tracheal position. ETT mediastinal localization accounts for fewer than 1% of all ectopic thyroid cases (2,3). Various surgical methods for approaching mediastinal masses have been documented in the literature, including median sternotomy, posterolateral thoracotomy, and, video-assisted thoracoscopic surgery (VATS) (4). More recently, robotic-assisted thoracoscopic surgery (RATS) has been proposed for these masses. The aim of this article is to present the use of robotic-assisted thoracoscopic surgery (RATS) for a rare case of a mediastinal ETT. Case presentation: We present the case of a 40-year-old male with no significant medical history who discovered a mediastinal mass on a thoracic CT scan following COVID-19 infection. Symptoms were dysphagia and anterior thoracic pain with cervical extension. Scintigraphy confirmed the presence of ectopic thyroid tissue in the mediastinum as well as a normal cervical thyroid gland. ETT was histologically confirmed by endoscopic ultrasound guided biopsy. Robotic assisted surgery was the chosen approach to surgically treat this mass and the technical details are presented. The mass was extracted through the cervical incision. Total surgical time was 230 minutes, and the blood loss was 60 ml. The patient was discharged after 48 hours with follow up showing a full recovery with no residual pain or respiratory symptoms. Conclusion: Ectopic thyroid tissue (ETT) is a rare cause of mediastinal masses, and the diagnosis is always a challenge. Robotic assisted thoracoscopic surgery was proved to be safe and efficient in this rare case of ETT developed in the superior mediastinum.

Dual Ectopic Thyroid: A Case Report.

Background: Ectopic thyroid gland is an uncommon disorder in which thyroid tissue is located along the line of migration, dual ectopic thyroid is a rare entity where parts of the gland are located in two different locations. Case: A 14-year-old girl presented with dysphagia and odynophagia of six years duration with worsening of two weeks. Physical exam showed tongue base mass. Imaging revealed two enhancing masses at the tongue base and inferior to the hyoid bone. A diagnosis of dual ectopic thyroid was made. Conclusion: Dual ectopic thyroid is a rare occurrence and proper diagnosis is essential for proper management.

Accessory Thyroid Tissue Detected Using 131 I SPECT/CT Imaging.

ABSTRACT: Thyroid ectopia has been described as a rare congenital anomaly, characterized by the presence of a thyroid gland in locations other than the orthotopic pretracheal location. The prevalence of accessory thyroid tissue in patients undergoing postablative radioiodine therapy in a 12-month period at a tertiary hospital nuclear medicine department was assessed. Fifty-seven patients were treated between September 2020 and September 2021. Retrospective analysis identified the presence and location of all accessory thyroid tissue separate from the orthotopic pretracheal thyroid gland. Accessory thyroid tissue was present in 21.1% (12/57) of the patients. Accessory thyroid tissue was most commonly located in the lingual region.

Thyroid Scintigraphy of a Rare Case of Left Thyroid Lobe Hemiagenesis With Subacute Thyroiditis.

ABSTRACT: Thyroid hemiagenesis is a rare developmental anomaly. Patients with thyroid hemiagenesis have higher incidence of coexisting thyroid disorders in the remaining lobe. We present a rare case of a 21-year-old woman with subclinical hyperthyroidism incidentally found to have thyroid hemiagenesis on thyroid 123I-Na scan, which is confirmed on thyroid ultrasound. On scintigraphy, only the right lobe showed activity. Thyroid ultrasound demonstrated that the right lobe was normal without any nodule. The left lobe was not visualized. This patient's thyroid uptake and scan also revealed low uptake in the remaining right thyroid lobe in keeping with subacute thyroiditis.

Papillary Thyroid Carcinoma in Ectopic Thyroid Tissue Within a Suspected Cervical Paraganglioma.

ABSTRACT: Ectopic differentiated thyroid carcinoma represents less than 1% of all thyroid carcinoma cases, which usually arises along the cervical midline, and (delving into literature) there are scarce reports of such entity in nuclear medicine imaging studies. We present a rare case of a confirmed synchronous, orthotopic, and heterotopic (in lateral ectopic thyroid tissue) differentiated thyroid carcinoma in a patient who was previously misdiagnosed as having a cervical paraganglioma, based on compatible clinical, analytical, and imagenological (both structural and functional) findings.

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.

An Unusual Posterior Mediastinal Mass - Ectopic Thyroid within the Oesophagus.

Presence of ectopic thyroid tissue in unusual locations is a rare phenomenon. Herein we present the case of a 55 year old lady, who on evaluation of dyspnoea was detected to have a mediastinal mass. Initial radiological evaluation showed the presence of a mass arising from the wall of the oesophagus which was presumed most likely to be leiomyosarcoma. She underwent surgical resection of the mass, but on histopathological examination, it turned out to be a nodular goiter which was lying within the smooth muscle layer of the oesophageal wall.

A rare presentation of ectopic thyroid gland at right axilla.

The thyroid gland and its hormones play important roles in organ development and in the homeostatic control of physiological mechanisms in human beings. As a result of embryogenic descent of thyroid gland, it commonly resides along the midline - from tongue to mediastinum (90%). Ectopic thyroid gland is a rare occurrence, with extra-lingual ectopic thyroid gland being even rarer. Thus, there is a concern for malignant metastasis. Madam H, a 56-year-old healthy woman presented to the Hospital Sultanah Nora Ismail, Johor, Malaysia in April 2020 with an increasing size of right axilla mass and history of weight loss. She was having right axilla mass for the previous 7 years but only noticed the increase in size about 1 year ago. She has no other constitutional symptoms. A tru-cut biopsy performed demonstrated a benign ectopic thyroid tissue. Thyroid function test showed primary hypothyroidism. Serum Chromogranin A and other thyroid antibodies were within the normal value. Further radiological imaging showed the normal thyroid gland at neck, with no signs of distant malignancy. There was no other axillary, mediastinal or hilar lymph node enlargement. She was started on regular T. L Thyroxine 100mcg daily and given regular follow-up in endocrine clinic. Benign ectopic thyroid gland is an unusual finding. As such, follow up is needed with possibility of carcinomatous transformation such as papillary carcinoma should be considered.

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.

Infants Diagnosed with Athyreosis on Scintigraphy May Have a Gland Present on Ultrasound and Have Transient Congenital Hypothyroidism.

Scintigraphy using technetium-99m (99mTc) is the gold standard for imaging the thyroid gland in infants with congenital hypothyroidism (CHT) and is the most reliable method of diagnosing an ectopic thyroid gland. One of the limitations of scintigraphy is the possibility that no uptake is detected despite the presence of thyroid tissue, leading to the spurious diagnosis of athyreosis. Thyroid ultrasound is a useful adjunct to detect thyroid tissue in the absence of 99mTc uptake. AIMS: We aimed to describe the incidence of sonographically detectable in situ thyroid glands in infants scintigraphically diagnosed with athyreosis using 99mTc and to describe the clinical characteristics and natural history in these infants. METHODS: The newborn screening records of all infants diagnosed with CHT between 2007 and 2016 were reviewed. Those diagnosed with CHT and athyreosis confirmed on scintigraphy were invited to attend a thyroid ultrasound. RESULTS: Of the 488 infants diagnosed with CHT during the study period, 18/73 (24.6%) infants with absent uptake on scintigraphy had thyroid tissue visualised on ultrasound (3 hypoplastic thyroid glands and 15 eutopic glands). The median serum thyroid-stimulating hormone (TSH) concentration at diagnosis was significantly lower than that in infants with confirmed athyreosis (no gland on ultrasound and no uptake on scintigraphy) (74 vs. 270 mU/L), and median free T4 concentration at diagnosis was higher (11.9 vs. 3.9 pmol/L). Six of 10 (60%) infants with no uptake on scintigraphy but a eutopic gland on ultrasound had transient CHT. CONCLUSION: Absent uptake on scintigraphy in infants with CHT does not rule out a eutopic gland, especially in infants with less elevated TSH concentrations. Clinically, adding thyroid ultrasound to the diagnostic evaluation of infants who have athyreosis on scintigraphy may avoid committing some infants with presumed athyreosis to lifelong levothyroxine treatment.

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.

Ectopic thyroid tissue at the skull base: a case report.

Ectopic thyroid tissue is a rare entity, resulting from developmental abnormality during the migration of the embryonic thyroid germ from the floor of the primitive foregut to its final pre-tracheal position. Although ectopic thyroid tissue may be located anywhere, its location at the skull base is extremely rare. We report a case of ectopic thyroid tissue at the skull base in a 19-year-old man with multimodality imaging findings.

Three-dimensional microscopy and image fusion reconstruction analysis of the thyroid gland during morphogenesis.

Thyroid dysgenesis (TD) is a major cause of primary congenital hypothyroidism; however, the molecular mechanism underlying this process is unclear. Current knowledge regarding the morphogenesis of the thyroid gland and vascular anomalies affecting thyroid development is limited. To monitor the early stages of thyroid gland development, we generated double transgenic zebrafish embryos Tg(tg:mCherry/flk1:EGFP). We described the volume of the thyroid from 2 days postfertilization (dpf) to 5 dpf using 3D reconstruction images. We treated zebrafish embryos with the fibroblast growth factor (FGF) inhibitor PD166866 to better understand the impact of vascular defects on thyroid development and the effects of drug administration at specific time periods on different stages of thyroid development. The 3D reconstruction data revealed that the thyroid glands underwent significant transformation at critical time points. PD166866 treatment from 48 to 72 hours postfertilization (hpf) and from 72 to 96 hpf did not cause obvious reductions in thyroid volume but did result in observable abnormalities in thyroid morphology. The treatment also affected thyroid volume from 36 to 48 hpf, thus indicating that there are time-point-specific effects of drug administration during thyroid development. Three-dimensional image reconstruction provides a comprehensive picture of thyroid anatomy and can be used to complement anatomical fluorescence information. The effects of an FGF pathway inhibitor on thyroid development were determined to be time-point-dependent.