Thyroid tissue outside the thyroid gland: Differential diagnosis and associated diagnostic challenges.

The presence of thyroid tissue outside of the thyroid gland may occur in various clinical settings and anatomic locations and includes both benign and malignant differential diagnoses. Some of these entities include thyroglossal duct cyst, lingual thyroid, parasitic nodule, thyroid tissue within a lymph node and struma ovarii. In routine daily practice, these entities do pose diagnostic challenges for the pathologists. Differential diagnostic considerations depend largely on the location of lesion and the histologic features. A definitive diagnosis may remain unclear in some cases while knowledge is still evolving in others i.e., incidentally detected bland appearing thyroid follicles in a lateral neck lymph node. This article aims to elaborate on the various entities characterized by thyroid tissue outside of the thyroid gland, both benign and malignant, and the relevant differential diagnostic considerations.

TORS excision of lingual thyroid carcinoma: Technique and systematic review.

OBJECTIVE: Clinically significant lingual thyroid tissue has a prevalence of 1/3000-10,000, and in 70% of these individuals, the lingual thyroid is their only thyroid tissue. Malignant transformation is exceedingly rare. Herein, we present a case of lingual thyroid carcinoma with a systematic literature review and description of our treatment technique. DATA SOURCES: PubMed, Ovid. REVIEW METHOD: The primary author performed a search of the literature for reports of lingual thyroid carcinoma or ectopic thyroid carcinoma associated with the tongue. Articles that did not present novel data, presented cases of ectopic thyroid carcinoma outside the tongue, non-malignant cases, non-thyroid carcinomas, or were non-English articles were excluded. Studies were limited to those published in the last 60 years. RESULTS: There are 39 cases reported in the literature. 23 cases occurred in females. Age at diagnosis ranged from 12 to 86; cases were more commonly diagnosed in the second decade of life, then in the 5th and 6th decades of life. Dysphagia, globus sensation, episodes of bleeding, voice changes, and presence of a neck mass were common symptoms at initial presentation. Nearly all patients underwent some form of pre-operative imaging, but practices varied as to the type of imaging. Treatment included surgical excision of the tumor in all but one case that was successfully treated with radioactive iodine therapy alone. CONCLUSIONS: Surgeons should be aware of lingual thyroid, its presentation, workup, and carcinoma treatment. Tumors are amenable to surgical excision, possibly followed by radioactive iodine therapy. Advances in robotic and endoscopic surgery over the past decade now allow for less morbid excisions of lingual thyroid tumors.

[Ectopic thyroid basi-lingual: A case report].

Introduction: The thyroid ectopic gland is a rare anomaly, especially when it's a lingual thyroid. It is characterized by aspecific clinical presentation, causing a diagnostic problem. The diagnosis is based on a combination of imaging techniques as well as histological examination. Case presentation: We are presenting a case of a patient with thyroid basi-lingual treated surgically. Discussion: The low incidence of ectopic lingual thyroid , and their clinical variability requires radiological and isotopic investigations. Conclusion: The diagnosis of this disease is primarily histological. The management of these ectopic thyroid is surgical.

Ectopic lingual thyroid with subclinical hypothyroidism in children.

OBJECTIVES: Lingual thyroid is a rare condition that affects approximately 1 in 100,000 individuals. Although it is usually detected in the pediatric population through newborn screening tests or evaluation of congenital hypothyroidism, there are cases in which it remains undetected until adulthood or until symptoms arise because of glandular enlargement. The possible symptoms of lingual thyroid include foreign body sensation in the throat, dysphagia, dyspnea, and hemorrhage. Several cases of lingual thyroid are asymptomatic and accompanied by subclinical hypothyroidism. Herein, we present three cases of lingual thyroid treated with thyroid hormone suppressive therapy. CASE PRESENTATION: The three patients sought medical attention because of a sore throat or foreign body sensation in the throat. Their newborn screening tests and developmental histories were normal. These patients exhibited subclinical hypothyroidism and were treated with hormone suppression therapy. CONCLUSIONS: Patients with lingual thyroid frequently exhibit subclinical hypothyroidism. Hormone treatment may help to reduce the size of the ectopic thyroid and improve symptoms. If an increase in size is noted during follow-up or symptoms do not improve, surgical treatments may be considered.

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.

Obstructive lingual thyroid; suprahyoid intracervical surgical procedure - A case report. / Tiroides lingual obstructivo, intervención quirúrgica vía transcervical suprahioidea: reporte de un caso.

INTRODUCTION: The treatment of lingual thyroid is controversial and should be individualized. Options include hormonal replacement, surgery in the presence of bleeding and obstruction of the airway and the digestive tract, and radioisotope therapy. CLINICAL CASE: 8-year-old girl presenting with discomfort when swallowing. A pink, well-vascularized mass, not painful or ulcerated, protruding from the base of the tongue and virtually closing the whole oropharynx, was observed. Absence of thyroid tissue in its normal position was reported by the ultrasound department. Cervical computed axial tomography confirmed the diagnosis and the presence of pharyngeal obstruction. Thyroid hormone replacement was established. As a result of dysphagia symptom progression, surgery was indicated. Thyroid removal was performed by means of a cervicotomy, with re-implantation of thyroid tissue laminas. The postoperative course was uneventful and replacement treatment was maintained, with an excellent clinical status four years later.

INTRODUCCION: El tratamiento de la tiroides lingual es controvertido y debe individualizarse. Las opciones incluyen el reemplazo hormonal, cirugía en presencia de hemorragia y obstrucción de la vía aérea o digestiva, y la terapia con radioisótopos. CASO CLINICO: Niña de 8 años de edad, con molestias a la deglución. Se observa masa rosada, muy vascularizada, no dolorosa ni ulcerada, que protruye desde la base de la lengua y cierra prácticamente toda la orofaringe. Ecografía informa ausencia de tejido tiroideo en su posición normal. Tomografía axial computarizada cervical comprueba el diagnóstico y la obstrucción faríngea. Se indicó tratamiento sustitutivo de las hormonas tiroideas. Ante la progresión de los síntomas de disfagia, se indicó cirugía. Se describe la exéresis tiroidea por vía cervical, suprahioidea, con reimplante de láminas de tejido tiroideo. Evolucionó sin complicaciones y se mantiene tratamiento sustitutivo, con excelente estado clínico después de cuatro años.

Lingual ectopic papillary thyroid carcinoma: Two case reports and review of the literature.

Ectopic thyroid occurs when it is not located on the normal thyroid compartment. While 90% of the ectopic thyroids were located at the base of the tongue, only 1% were lingual thyroid carcinoma (LTC). Only 56 LTC cases have been reported so far. Here we reported two cases of LTC. Patient 1 was a 47-year-old female with LTC and co-current sub-hyoid ectopic thyroid. She experienced major hematemesis and dyspnea requiring emergent tracheotomy. Patient 2 was a 61-year old female who was presented with LTC with multiple lymph node metastasis and bilateral lung metastasis. Both of the patients' lingual masses were removed via trans-submaxillary excisions. Pathology revealed ectopic papillary thyroid carcinoma. Then they were treated with radio-active iodine (RAI). These patients had full recovery and there were no complications. A review of literature was also presented.

Modified approach for lingual thyroid transposition: report of two cases.

Lingual thyroid is a rare congenital anomaly of thyroid development resulting from failure of the thyroglossal duct to migrate from the foramen cecum to the prelaryngeal site. The lingual thyroid associated with a fetal adenoma is even more unusual. We presented two cases of lingual thyroid, one associated with fetal adenoma. The ectopic gland was transposed into the muscle space at the floor of the mouth using an extraoral midline lower lip, mandible and tongue-splitting approach in case 1, and a transoral lower lip degloving and midline mandibulotomy and tongue-splitting approach in case 2. Sixteen-year follow-up of case 1 and 6-month follow-up of case 2 showed that the transposed thyroids achieved normal function. Case 2 had no visible scar in the lower lip and mental area. Surgical transposition of the lingual thyroid to the floor of the mouth with the vascular supply intact offers a promising approach for the treatment of this anomaly. The transoral lower lip degloving and midline-splitting approach is recommended because of its better cosmetic outcome.

Transoral videolaryngoscopic surgery for papillary carcinoma arising in lingual thyroid.

Carcinoma arising in lingual thyroid is an extremely rare entity accounting for only 1% of all reported ectopic thyroids. Here, we report a case of carcinoma arising in lingual thyroid, which has been successfully managed by transoral resection and bilateral neck dissections. A lingual mass 4-cm in diameter with calcification was incidentally detected by computed tomography at medical check-up. No thyroid tissue was observed in normal position. Ultrasound examination showed bilateral multiple lymphadenopathies. Fine needle aspiration biopsy from lymph node in his right neck was diagnosed as Class III and thyroglobulin level of the specimen was 459ng/ml. Due to the difficulty in performing FNA of the lingual masses, right neck dissection was performed in advance for diagnostic purpose. Pathological examination showed existence of large and small follicular thyroid tissues in several lymph nodes, suggesting lymph node metastasis from thyroid carcinoma. Two months after the initial surgery, video-assisted transoral resection of lingual thyroid with simultaneous left neck dissection was performed. Postoperative course was uneventful. Papillary carcinoma was found in the lingual thyroid and thyroid tissues were also found in left cervical lymph nodes. Video-assisted transoral resection was useful for the treatment of thyroid cancer arising in lingual thyroid.

Is it possible to determine the origin of cyst in empty thyroid bed in patient with lingual thyroid?

Some patients with ectopic thyroid gland or athyreotic patients have one or more cysts in empty thyroid bed. The origin of these cysts is uncertain. We present the patient with lingual thyroid gland and small cyst in empty thyroid bed featuring the diagnostic algorithm used and discussing the possible etiologic scenarios.

[Vesicular carcinoma in lingual thyroid: a rare case]. / Carcinome vesiculaire sur thyroïde linguale: cas rare.

Lingual thyroid is secondary to the absence of migration of the thyroid diverticulum. The latter develops locally, that is, at the level of the foramen caecum. It may be the only thyroid tissue present, or it may be associated with a normal thyroid. The occurrence of a lingual thyroid carcinoma is rare accounting for about thirty cases described in the literature. This study reports a case of vesicular carcinoma in lingual thyroid.

Obstructive lingual thyroid causing sleep apnea: a case report and review of the literature.

Lingual thyroid has been reported to cause obstructive sleep apnea (OSA) only once in the literature. We present a case of a 49-year-old nonobese female with a 2-year history of progressive snoring, apneas, snort arousals, and daytime somnolence associated with the sensation of an 'enlarging tongue'. She was found to have severe OSA caused by a large lingual thyroid. While positive airway pressure therapy was not successful, surgical resection of the thyroid was curative. OSA caused by lingual thyroid and other oropharyngeal/parapharyngeal tumors are discussed. A careful oropharyngeal examination is important in evaluating patients with complaints of OSA.

Evidence for calcitonin-producing cells in human lingual thyroids.

CONTEXT: The thyroid contains two types of cells, the thyroid follicular cells and the calcitonin-producing cells. The site of origin of the thyroid follicular cells is the median thyroid anlage, an endothelial diverticulum in the midline of the ventral pharynx between the first and the second pharyngeal pouches. The ultimobranchial bodies (UBB), a pair of transient embryonic structures evaginated from the fourth pharyngeal pouch and located symmetrically on the sides of the developing neck, are the source of calcitonin-producing cells. In human embryos, the thyroid bud starts its migration at embryonic day 24 and reaches its final location in front of the trachea at embryonic day 45-50. The UBB fuse with the primitive thyroid when thyroid migration is completed. Lingual thyroids result from the failure of the thyroid precursor cells to migrate from the primordial pharynx to the anterior part of the neck. Therefore, calcitonin-producing cells are not expected to be present in lingual thyroids. OBJECTIVE: Our objective was to determine whether calcitonin-producing C cells are present in ectopic lingual thyroids. DESIGN, SETTING, PATIENTS, AND MAIN OUTCOME MEASURE: We performed calcitonin immunolabeling and transcript detection on four flash-frozen ectopic lingual thyroids. Additional calcitonin immunolabeling was performed on two other paraffin-embedded ectopic lingual thyroids. RESULTS: We report evidence of calcitonin-producing cells in six independent cases of ectopic lingual thyroids. CONCLUSION: The UBB are not the only source of calcitonin-producing cells in humans. Interactions between calcitonin-producing and thyroid follicular cells occur earlier than previously accepted.

Papillary carcinoma in a lingual thyroid: an unusual presentation.

A lingual thyroid is a mass of ectopic thyroid tissue located in the midline of the base of the tongue. Its estimated prevalence ranges from 1 in 3,000 to 1 in 10,000 population. We report the interesting case of a 28-year-old woman who presented with a primary papillary carcinoma in a lingual thyroid and a histologically normal thyroid gland. To the best of our knowledge, this case probably represents only the second reported case of a follicular variant of a papillary carcinoma arising in a lingual thyroid.