Heterotopic Thyroid Research Articles

Mucoepidermoid Carcinoma of the Thyroglossal Duct: Two Rare Entities in a Unique Case Report.

Mucoepidermoid Carcinoma (MEC) of the thyroid represents less than 0.5% of all thyroid neoplasms. Thyroglossal duct cyst carcinoma is a rare condition with only approximately 300 cases reported. A 34-year-old pregnant woman at 37 weeks gestation presented to an endocrinological center for primary autoimmune hypothyroidism. The thyroid ultrasound revealed a pseudonodular pattern. The patient was followed up after two years. She reported a full-term delivery without complications. A new thyroid ultrasound was performed, showing a cystic lesion in the median suprathyroid area, measuring 6 x 9 x 10 mm, not previously reported. After 4 months, the suprathyroid cystic lesion was confirmed by thyroid ultrasound, measuring 6 x 11 x 12 mm. The patient was referred for fine-needle aspiration cytology. Cytological examination showed lymphocytes, red blood cells, and some epithelial aggregates with large cytoplasm and nuclear polymetrism with oxyphilic aspects. The patient underwent the Sistrunk procedure for the suprathyroid lesion. The histological examination revealed lymphocytic thyroiditis in heterotopic thyroid tissue with solid cell nest, epidermoid epithelium, and mucus-secreting cells suggestive of low-grade mucoepidermoid carcinoma. The immunohistochemistry study was positive, exhibiting thyroid transcription factor 1 and cytokeratin-19. No positivity was observed for thyroglobulin, calcitonin, galectin-3, and Hector Battifora mesothelial antigen 1. The recent follow-up examination, 13 months after the surgery, has been found negative for disease recurrence. This is the first case of an MEC occurring within a thyroglossal duct. Considering the age of the patient, the histological diagnosis, and the absence of thyroid nodules and metastasis, we decided on the Sistrunk procedure without total thyroidectomy.

Introducing a very rare case of intra-pericardial thyroid tissue with blood supply from the aortic arch in a patient with renal cell carcinoma: A case report and review of the literature

Intra-pericardial heterotopic thyroid (IPHT) is an incidental finding during open-heart surgery. Although heterotopic thyroid has been reported in different parts of the body, only a few cases of intra-pericardium have been reported so far. In most articles, intracardiac, intrathoracic and heterotopic thymus cases are mistakenly included as IPTH cases A 57-year-old man with a history of non-Hodgkin lymphoma, who was treated 8 years ago and recovered, is now a candidate for surgery due to clear cell renal carcinoma in the left kidney with inferior vena cava (IVC) thrombus tumor that has spread into the right atrium. At the same time, he was operated on by two teams of urology and heart surgery. The patient’s kidney was removed, and then he was subjected to sternotomy by the heart surgery team to remove the thrombus tumor. After opening the pericardium inside the pericardial cavity, a pericardial mass measuring 1×2 ×3 cm, which was connected to the lower surface of the aortic arch by a 1 cm long stalk, was observed. It was resected and sent to pathology laboratory. The rest of the surgery to remove the thrombus tumor from inside the right atrium and IVC continued according to the procedure. The pathological report was benign thyroid tissue. Actual cases of IPTH are underreported, and due to the small number, it is not yet possible to comment on the prevalence of malignancy in it or its functional role; However any lesion or abnormal mass in the pericardial cavity should be respected and sent to pathology laboratory therefore by collecting information about these masses, in the future, decisions can be made and summarized.

Rat thyroid graft transplantation after cryopreservation with scintigraphic standardization for an experimental study

PurposeBudget cuts among other factors undermine the use of state-of-the-art equipment by many research groups. This doesn't mean that their scientific data are not reliable or top-notch. Resort to adaptations is a recurrent need in their reality. The aim of this study was to assess whether scintigraphy with 99mTcO4 is effective in evaluating the functionality of thyroid grafts after cryopreservation in rats. Material and methods24 rats were randomly distributed into 3 groups: Control Group (CG), without surgical procedure, Hypothyroidism Group (HTG), submitted to total thyroidectomy, and Transplanted Group (TG), with total thyroidectomy and cryopreservation of the thyroid gland for 7 days followed by grafting of a thyroid lobe. A protocol using a gamma camera imaging was conducted fourteen weeks after transplantation, and the whole body 99mTc, focusing on the topic of heterotopic thyroid uptake was evaluated. ResultsThe images acquired had good quality with no noise and artifacts that could jeopardize its analysis. On the 14th day, HTG displayed no thyroid uptake, and the TG had a clear uptake of the thyroid graft in the topography of the biceps femoris muscle. Presented data also showed that both equipment spatial resolution and alignment (4.375 mm) did not interfere with the physiological uptake of 99mTc by the thyroid graft. ConclusionThe viability and functionality of cryopreserved thyroid autotransplantation in rats who underwent total thyroidectomy were successfully accessed by the scintigraphy protocol developed.

Thyroid autotransplantation after total thyroidectomy in multi-nodular goiter—a case series analysis

Following the success of parathyroid autotransplantation, thyroid autotransplantation was introduced, aiming to avoid or reduce the severity of post-thyroidectomy hypothyroidism in noncompliant patients. While our primary aim was to assess the survival and function of heterotopic autotransplanted thyroid tissue after total thyroidectomy, our secondary aim was to establish a relationship between autotransplanted volume and euthyroid state. We conducted a case series analysis, including 40 women diagnosed with multinodular goiter for whom total thyroidectomy was considered. Patients were randomized into two groups: group A (20 patients) who received 15 g and group B (20 patients) who received 10 g of healthy non-nodular thyroid tissue. Survival and function of heterotopic autotransplanted thyroid tissue was assessed by hormonal profile and thigh ultrasound scan (site of autotransplanted thyroid graft) 2, 6, and 12 months postoperatively. We have included 40 ladies divided into two groups: group A 50 years. There was no statistically significant difference between group A and group B regarding radioactive iodine uptake after the 2nd, 6th, and 12th months. There was a statistically significant difference between results after the 2nd, 6th, and 12th months regarding free T3 (FT3; tri-iodothyronine), free T4 (FT4; thyroxine), thyroid-stimulating hormone, and pulse (p ≤ 0.001). The study revealed a highly statistically significant difference between the 2nd, 6th, and 12th months in FT3, FT4, and TSH levels and pulse (p ≤ 0.001) as well as highly statistically significant difference between group A and group B regarding FT3 and FT4 after the 2nd, 6th, and 12th months (p ≤ 0.001) (Tables 2 and 3). Autotransplanted thyroid tissue processing and injection time range was 18–20 min, and none of the patients had immediate or delayed complications. We found the procedure to be safe, successful, and not time-consuming; we also found that better results were achieved when larger volumes were implanted in younger patients.

Assessment of Survival and Function of Heterotopic Auto-transplanted Thyroid Tissue after Total Thyroidectomy for Non-toxic Multinodular Goiters

Assessment of Survival and Function of Heterotopic Auto-transplanted Thyroid Tissue after Total Thyroidectomy for Non-toxic Multinodular Goiters

Thyrolipoma: A Rare Thyroid Gland Entity

Fat-containing thyroid swellings are rare with limited differentials including lipomatous goiter, heterotopic thyroid rests, amyloid goiter, lymphocytic thyroiditis, Grave’s disease, adenolipoma, intrathyroid thymic or parathyroid lipoma, encapsulated papillary carcinoma, and liposarcoma etc. We present a case of a 60-year-old euthyroid female with a long standing thyroid swelling radiologically and pathologically diagnosed as thyrolipoma (adenolipoma). Thyrolipomas are occasionally diagnosed. However, these lesions are considered to be benign and are treated surgically.

Heterotopic thyroid autotransplantation: A preliminary clinical study.

Thyroid autotransplantation offers an attractive alternative to subtotal thyroidectomy and replacement therapy. However, it has not been sufficiently clinically investigated. Total thyroidectomy was performed for 20 patients with benign thyroid disorders, and at least 10 g of thyroid tissue were implanted intramuscularly. Graft monitoring was achieved through 99m Tc scan at 2 months, free triiodothyronine (FT3), FT4, and thyroid-stimulating hormone (TSH) measurements at 1, 2, 4, 6, 8, 10, and 12 months postoperatively, and clinical examination. Grafts survived and gradually functioned in all patients to a variable extent after a latent period (mean 99m Tc uptake = 1.28 ± 0.37%). Mean values for FT3, FT4, TSH at 12 months were 1.75 ± 0.48 pg/mL, 1.06 ± 0.26 ng/dL, and 28.08 ± 34.01 μIU/mL respectively. Thyroid autotransplantation restored euthyroid status in 33.3% of patients after 12 months. A role of age, operative time, and 99m Tc-uptake in determining the final graft outcome is possible.

Review of Heterotopic Thyroid Autotransplantation.

Total thyroidectomy is increasingly accepted for the management of bilateral benign thyroid disorders. Postoperatively, patients require lifelong levothyroxine replacement therapy to avoid postoperative hypothyroidism, which besides the burden of compliance, has been proven to be associated with several long-term side effects. Heterotopic thyroid autotransplantation was proposed several decades ago to avoid the need for life-long postoperative replacement therapy with maintaining the autoregulatory mechanism of thyroxin production inside the body according to its needs. Available data regarding this topic in literature is relatively poor. Before applying thyroid autotransplantation on humans, several studies have been done on animals, where the autologous transplantations were found to be successful in almost all the cases, proved by follow up postoperative 8-week measurements of thyroid hormones and histopathological examination of the removed autografts. Regarding the clinical application, few trials have been done using cryopreserved in vivo, in vitro or immediately autotransplanted thyroid autografts. Satisfactory results were obtained, however, the number of these studies and the number of patients per each study was very low. Besides the study methodologies were not so consistent.

CASE REPORT Heterotopic thyroid tissue of the uvula

It is acknowledged that the uvula’s “structure’s function appears in the literature in only the briefest fashion”. It has also been declared that “Disorders of the palatal uvula are one of the least highlighted areas of medical literature”. Therefore, we present a most rare case of heterotropic thyroid tissue found in this organ in Nigeria. It is an addition to the worldwide appreciation of this unique entity.

Heterotopic thyroid cancer in pelvts:a case report

Heterotopic thyroid cancer in pelvts:a case report

Thyroid Carcinomas Found Incidentally in the Cervical Lymph Nodes: Do They Arise From Heterotopic Thyroid Tissues?

Thyroid carcinomas have been found incidentally in the cervical lymph nodes during surgery for head and neck squamous cell carcinoma (SCC). Such carcinomas have been considered a metastatic focus for malignant transformation of heterotopic thyroid tissue. We report on cases of so-called occult thyroid carcinoma in the cervical lymph nodes, and review the relevant literature. We encountered 3 cases of incidental papillary carcinoma in the cervical lymph nodes of patients with oral SCC, and consequently reviewed 75 previously reported cases. Among 148 patients with oral SCC who had undergone cervical lymph node dissection, 3 were diagnosed with occult thyroid carcinoma. Papillary carcinomas were found in 3, 10, and 3 lymph nodes in cases 1, 2, and 3, respectively. Computed tomography showed 2 tumor-like shadows and 1 calcified mass in the thyroid gland in cases 2 and 3, respectively. These shadows did not enlarge during the 3 to 5 years of observation, and all patients are alive, without any events related to the neck and thyroid gland. Among the reviewed cases, approximately two fifths were histopathologically or clinically free from thyroid carcinoma. Progressive thyroid carcinoma was not detected in any patient. We propose the possibility that thyroid carcinoma in the cervical lymph nodes is not necessarily metastatic, but may occasionally arise from heterotopic thyroid tissue.

Comparative thyroidology: thyroid gland location and iodothyronine dynamics in Mozambique tilapia (Oreochromis mossambicus Peters) and common carp (Cyprinus carpio L.)

In teleosts, the thyroid gland is mostly found in the subpharyngeal region. However, in several species thyroid follicles are found in, for example, heart, head kidney and kidney. Such heterotopic thyroid follicles are active, and considered to work in concert with the subpharyngeal thyroid. In Mozambique tilapia (Oreochromis mossambicus) thyroid activity is, indeed, restricted to the subpharyngeal region; in common carp (Cyprinus carpio) the functional endocrine thyroid is associated with renal tissues. The subpharyngeal follicles of carp comprise only 10% of the total thyroid tissue, and these follicles neither accumulate iodide nor synthesize or secrete thyroid hormones to a significant degree. Although the shape and size of carp subpharyngeal and renal follicles vary, the epithelial cell height of the thyrocytes and thyroxine immunoreactivity do not differ, which suggests that the activity of the carp subpharyngeal thyroid follicles is dormant. Differences in thyroid physiology between the two fish species were further assessed at the level of peripheral thyroid hormone metabolism. Carp clears plasma of thyroid hormones faster than tilapia does. Furthermore, a significant amount of conjugated thyroid hormones was observed in the plasma of tilapia, which was preceded by the occurrence of thyroid hormone conjugates in the subpharyngeal region and coincides with the appearance of conjugates in the surrounding water. Apparently, plasma thyroid hormone conjugates in tilapia originate from the thyroid gland and function in the excretion of thyroid hormones. Our data illustrate the variability in teleostean thyroidology, an important notion for those studying thyroid physiology.

Heterotopic intrathymic thyroid tissue

Heterotopic intrathymic thyroid tissue is an extremely rare condition, but it is important to distinguish it from metastases of clinically undetected thyroid carcinoma because metastatic papillary thyroid carcinoma is often so well differentiated, simulating normal thyroid tissue. Described herein are histological findings of heterotopic intrathymic thyroid tissue that was incidentally identified in a woman with papillary thyroid carcinoma during histological examination of a radical neck dissection specimen. These findings emphasize that this rare incidence may occur and should be differentiated from metastatic papillary carcinoma. Histologically, the patient's intrathymic thyroid follicles were identical to the normal thyroid follicles, having flat cuboidal cells with uniformly small nuclei without nuclear grooves or inclusions. The follicular cells had a low Ki-67 labeling index close to zero, and immunonegativity for galectin-3, HBME-1, and RET oncoprotein, in contrast to the tumor cells in primary papillary thyroid carcinoma of the patient. To the authors' knowledge this is the first case report of intrathymic heterotopic thyroid tissue posing a diagnostic difficulty in a patient with papillary thyroid carcinoma.

Large mediastinal mass of heterotopic thyroid tissue: a case report and review of literature

Incidental detection of a mediastinal mass in a asymptomatic patient poses a not easy diagnostic problem. For solid masses or cysts, histology or cytology is often necessary. Although substernal extension of a cervical goiter is common, totally intrathoracic primary thyroidal mass is unusual. We describe a rare case of heterotopic accessory mediastinal thyroid in a patient completely asymptomatic both for signs of thyroid dysfunction and mechanical compression. Radiological and hormonal 6 and 12 months follow-up is reported.

Heterotopic Thyroid

Heterotopia of the thyroid gland is veryuncommon. Ectopic thyroid results from embryologicaberration characterized by the existence ofthyroid tissue in a site other than its usual locationanterior to the trachea. Ectopic thyroid tissue isusually found along the path of initial descent ofthe thyroid, representing a failure of the thyroidto descend completely. Thyroid ectopia mayalso be found in locations other than the typicalpathway of embryologic descent. It is importantto consider ectopic thyroid as a differentialdiagnosis when a mass is discovered in the neck,chest, or, rarely, other locations.

Ectopic thyroid tissue in the left ventricular outflow tract

Ectopic thyroid tissue in the heart (struma cordis) is rare. The only report from a hemodynamically significant obstruction of the left ventricular outflow tract (LVOT) by a heterotopic thyroid gland was published in 1988. In our patient, a 42-year-old woman with recurrent chest pain, two spheric cardiac tumors were diagnosed by transthoracal echocardiography. One of the tumors, obstructing the LVOT, could successfully be resected under cardiopulmonary bypass. The pathologic examination showed a colloid-filled ectopic thyroid gland. The second tumor, which was entirely located in the submembraneous part of the interventricular septum, had no hemodynamic influence, and was left in situ to avoid surgical damage of adjacent intraseptal structures. The midterm follow-up showed no recurrence.

Thyroid Heterotopia as a Rare Cause of Intrapericardial Tumoral Mass: Case Report and Review of the Literature

This article describes the interesting discovery of a large tumoral mass formed of heterotopic thyroid tissue inside the pericardial cavity of an elderly man who died of unrelated causes. Heterotopic thyroid tissue may be found in many locations throughout the body. Intracardiac and intrapericardial locations, however, are exceptionally rare—this is only the second report of intrapericardial thyroid heterotopia. Such cases may be explained by the proximity of the developing cardiac structures and the foregut, the latter containing thyroid primordia during early embryogenesis.

The thyroid of the sarcopterygian fishes (dipnoi and crossopterygii) and the origin of the tetrapod thyroid

The thyroid glands of the extant sarcopterygian fishes show the features which are retained in the thyroid glands of the tetrapods. Whole body scans of 131I injected dipnoans demonstrate a single thyroid area with no heterotopic thyroid present. The thyroids of all extant sarcopterygian genera are compact and encapsulated in contrast to diffuse thyroid tissue occurring in teleosts generally. The basic condition, a single median thyroid, is present in Neoceratodus forsteri and Latimeria chalumnae, while Lepidosiren paradoxa and Protopterus annectens show bifurcate thyroid glands. Cytomorphometric analysis of the thyroidal elements also reveals closer similarities to the Amphibia than to the teleosts. In addition, the Dipnoan radioiodine metabolism approximates that of the tetrapods rather than that of the teleosts. Thus, the fundamental features of the tetrapod thyroid were established in the Sarcopterygii early in the course of vertebrate evolution. Further, as in most of the higher vertebrate classes, parafollicular cells are not present in the sarcopterygian thyroid.

Heterotopic thyroid follicles in the accessory mesonephric lobes of Heteropneutes fossilis (Bloch).

The presence of heterotopic thyroid follicles is reported in the accessory mesonephric lobes of Heteropneustes fossilis. They are found rarely and singly, scattered in the substance of these lobes, in the early stages of development; but in the adult organ they occur in groups. There is no regular distribution and proper arrangement of these follicles. They are mainly located in close proximity to blood vessels and are considered to have migrated to their heterotopic positions along them. They show some signs of functional activity in the adult animal.

Histochemistry of Heterotopic Thyroid Tissue in the Human Ovary

Histochemistry of Heterotopic Thyroid Tissue in the Human Ovary