Ectopic thyroid gland. A clinical study of 30 children and review

Da Vinci robot-assisted resection to treat abdominal ectopic thyroid: a case report and literature review

Although ectopic thyroid can be found in thoracic locations, the discovery of abdominal ectopic thyroid is often an accidental event. Moreover, abdominal ectopic thyroid is easily misdiagnosed due to the rarity of these cases and the difficulties in the preoperative diagnosis process. Thus, we aimed to assess the prevalence and features of abdominal ectopic thyroid and to highlight the current knowledge about the clinical characteristics and management of this condition by analyzing a case report of abdominal ectopic thyroid and reviewing the literature. A 70-year-old woman with a 3-year history of gradually increasing abdominal distension in the right lower quadrant of the abdomen was admitted to the hospital. Contrast-enhanced computed tomography (CT) of the abdomen revealed a retroperitoneal mass. The patient underwent Da Vinci robotic surgery, and the retroperitoneal mass was completely resected. Subsequently, the pathologic diagnosis of the mass was ET. The patient had no discomfort or symptoms when she was discharged from the hospital and at the postoperative 1, 3, 6, 9 and 12 months follow-up. The summary of literature review suggested that abdominal ectopic thyroid is still rare although there are some reports. Nonetheless, the cause of abdominal ectopic thyroid is unclear, and abdominal ectopic thyroid has the following characteristics: more common in women than in men, asymptomatic in the majority of the cases, difficult to diagnose, and found by excluding metastasis. Most ectopic thyroid is treated with surgery, and minimally invasive techniques have been increasingly performed. This is the first report on Da Vinci robotic resection for large rare retroperitoneal ET, and this case highlights that ET should be considered when patients present with similar imaging findings in the abdomen.

The role of ¹²³I imaging in the evaluation of infants with mild congenital hypothyroidism

BACKGROUND/AIMS

Controversy exists regarding the diagnosis and treatment of mild congenital hypothyroidism (MCH). We studied the value of (123)I imaging in patients with MCH.

METHODS

Retrospective chart review of infants and children <4 years of age who underwent (123)I imaging: group 1 = MCH [thyroid-stimulating hormone (TSH) <25 µIU/ml, normal free T4/T3], group 2 = severe congenital hypothyroidism (TSH ≥25 µIU/ml), and group 3 = MCH in infancy imaged after treatment withdrawal at age 3 years. Data collected included 4- and 24-hour (123)I uptake, TSH, free T4/total T3 at imaging, age at imaging, and levothyroxine (L-T4) dose at 1 year of.

RESULTS

Thirty-six patients underwent (123)I imaging. In group 1 (n = 20, median TSH: 8.49 µIU/ml), 85% had abnormal imaging consistent with dyshormonogenesis. Two patients were referred after 1 year of age. The median age at imaging for the remaining 18 patients was 54 days. Median L-T4 dose at 1 year of age for these 18 patients was 2.8 μg/kg, which is consistent with dyshormonogenesis. Ninety-one percent of group 2 (n = 11, median TSH: 428.03 µIU/ml) had abnormal imaging. The median age at imaging was 13 days. Four patients in group 3 had abnormal (123)I imaging and restarted treatment.

CONCLUSION

(123)I imaging is a valuable tool for evaluation, diagnosis, and treatment of MCH.

Lingual Thyroidectomy

Objectives:

We report the clinical findings, surgical management, and outcomes for lingual thyroidectomy.

Methods:

We performed a retrospective case review of lingual thyroidectomy performed at 3 tertiary-care academic referral centers between 1994 and 2012.

Results:

Nine patients underwent lingual thyroidectomy for symptoms including globus sensation (6 patients), dysphagia (5 patients), and airway obstruction (5 patients). Before surgery, 3 patients had attempted medical suppressive therapy. Lingual thyroidectomy was performed by transoral laser microsurgery in 4 patients, transoral robotic surgery in 3 patients, transoral surgery without microscopic assistance in 1 patient, and an open approach with a modified Sistrunk procedure in 1 patient. Total thyroidectomy was attained in 7 patients, and subtotal resection in 2. The follow-up averaged 8 months, and all patients reported significant improvement in their symptoms. One patient had a recurrence. Complications included postoperative bleeding and epiglottic perforation in 1 patient and airway obstruction secondary to angioedema in another patient. There was no significant difference in operative times between transoral laser microsurgery (91 ± 16 minutes) and transoral robotic surgery (109 ± 35 minutes). Transoral surgery without microscopic assistance and open resection had longer operative times (206 and 246 minutes, respectively).

Conclusions:

Surgical resection of lingual thyroid glands achieves significant improvement in patient symptoms, with low rates of recurrence. We favor a total lingual thyroidectomy approach with use of either a microscope or a robotic endoscope for optical assistance.

Primary Intrathoracic Goiter

Nodular goiter is a common disease in Taiwan, and substernal or intrathoracic goiters are not infrequent. However, intrathoracic goiters are mainly of the secondary type and primary intrathoracic goiters are rarely seen. We report a 55-year-old woman who was incidentally found to have an ectopic goiter located in the anterior upper mediastinum with the initial presenting symptom of productive cough. Imaging studies including chest X-ray and computed tomography identified the lesion, and 131I-uptake scan showed weak uptake in the thorax. Surgical removal via thoracotomy was performed and the diagnosis was confirmed by pathology. A primary intrathoracic goiter, although rare, should also be considered in the differential diagnosis of mediastinal tumor.

Ectopic thyroid

Primary mediastinal ectopic goiters are very rare. We report a case in which an ectopic goiter with blood supply from the thoracic vessels necessitated a transternal approach for removal, resulting in a favorable outcome.

Lingual thyroid and hyperthyroidism: a new case and review of the literature

Lingual thyroid is the result of a defective migration of the thyroid anlage occurring between the 3rd and 7th week of gestation. Whereas mutations in the transcription factor-2 (TTF-2) and PAX8 and in the TSH receptor genes (TSH-R) have been reported in a minority of patients with thyroid dysgenesis, the etiopathogeny of the majority of cases, and in particular of thyroid ectopy, remains unclear. The majority of patients with thyroid ectopy are asymptomatic, but obstructive symptoms as well as hypothyroidism have been observed. Hyperthyroidism is an exceptionally rare finding. To our knowledge, only 2 cases have been reported in the literature to date. Herein, we describe an unusual case of thyrotoxicosis related to a nodular lesion in a lingual thyroid. Treatment consisted in restoration of a euthyroid state with thionamide followed by surgical removal of the ectopic gland. The underlying molecular cause of the ectopic lingual thyroid and the toxic adenoma in this case could not be identified. We speculate that abnormally early differentiation of the thyroid gland could interfere with the migration process, a hypothesis yet to be confirmed.

Ectopic lingual thyroid: an otolaryngologic emergency beyond childhood

Ectopic thyroid is rare and occasionally presents suddenly in childhood. Adult patients with thyroid ectopy who develop local symptoms commonly have an enlarged ectopic gland and hypothyroidism. We describe the first case of an adult patient who sudden presented with sudden dysphagia and dyspnea caused by a large lingual thyroid in clinical and biochemical euthyroidism. Treatment consisted of surgical removal of the ectopic gland and thyroid hormone replacement therapy.

Graves' disease and recurrent ectopic thyroid tissue

Ectopic thyroid tissue is the result of abnormal migration of the gland as it travels from the floor of the primitive foregut to its destined pretracheal position. The prevalence of ectopic thyroid tissue ranges between 7%-10%. Patients with ectopic thyroid tissue are usually euthyroid, but can present with signs and symptoms of upper aerodigestive tract obstruction. We report a case in which ectopic mediastinal thyroid tissue was removed surgically because of substernal chest pain. It recurred 9 years later when the patient developed Graves' disease. We propose that the recurrence of the ectopic thyroid tissue was due to the influence of thyroid stimulating immunoglobulins (TSI).

Thyroglossal duct cyst or ectopic thyroid gland?

We report a 16-year-old boy with an anterior midline neck mass clinically diagnosed as a thyroglossal duct cyst. An ultrasound scan performed prior to surgery suggested a normally located thyroid gland. Following surgical excision of the presumed thyroglossal duct cyst the patient became hypothyroid. A radioisotope scan confirmed no active thyroid tissue. A pitfall in the ultrasonographic identification of the thyroid gland is discussed.

Transient iodine organification defect in infants with ectopic thyroid glands

BACKGROUND

Thyroid gland ectopy is the most common cause in infants with congenital hypothyroidism (CH). Its association with iodine organification defect, as suggested by positive perchlorate discharge test (PDT) has been reported. However, whether such an association represents a true or transient defect has not yet been determined. This finding has an important clinical, epidemiological, and genetic implications.

OBJECTIVE

To determine the natural history of iodine organification defect in patients with CH caused by thyroid ectopy detected by neonatal screening.

DESIGN

Prospective longitudinal study.

SETTING

King Khalid University Hospital, Riyadh, Saudi Arabia.

PATIENTS AND METHODS

PDT was performed, at the time of diagnosis and follow-up, in infants who showed an enlarged ectopic thyroid gland with a Tc-99m pertechnetate uptake of 2% or more.

RESULTS

Of 115 neonates with ectopic thyroid glands, 19 showed an enlarged gland with Tc-99m uptake ranging from 2 to 3.2%. Perchlorate discharge test was performed in 13 of these and was consistent with iodine organification defect in nine. Repeated PDT in seven patients showed normal values.

CONCLUSION

The results of the authors' study indicate the transient nature of the iodine organification defect and suggest that a delay in the developmental of synthetic mechanisms occur in the dysgenetic glands.

Ectopic thyroid tissue presenting as a midline neck mass

Ectopic thyroid tissue can be found anywhere between the foramen cecum and the normal position of the thyroid gland. Although very uncommon, it is most often found in the region of the foramen cecum, in patients in whom the gland fails to descend. Extralingual thyroid tissue is most commonly located in the anterior cervical area, the region of the thyroglossal duct. It must be differentiated from thyroglossal duct cyst, in that it frequently represents the only source of thyroid tissue. In the majority of patients with lingual thyroid tissue, this is the only functioning thyroid. We present the case of a thirteen year old male child with a midline cervical mass first noted at one year of age. Since its early presentation, this midline mass had increased and decreased in size, and over the last three months had been associated with odynophagia and anterior neck swelling. A presumptive diagnosis of thyroglossal duct cyst was made. A preoperative thyroid scan revealed that this midline mass was in fact the only functioning thyroid tissue; therefore no surgery was performed. This case demonstrates the essential role of a thyroid scan in the preoperative evaluation of a midline neck mass. Recognizing that ectopic thyroid tissue may present as a thyroglossal duct cyst and may be the only functioning thyroid avoids subjecting the child to inappropriate surgery and a life of replacement therapy.

Relationship between height, sitting height and subischial leg length in Dutch children: presentation of normal values

A widely used method of judging body proportions is to consider the ratio of sitting height to height (SH/H) related to age. A drawback of this method is that only one derived variable is used. A pairwise consideration of the original measurements provides more information. In this study data from the cross-sectional Oosterwolde I growth study are used to present normal values for the ratio SH/H for age, as well as values for sitting height related to height and subischial leg length. A comparison is made with other studies.

Lingual thyroid: a new surgical approach--a case report

Ectopic lingual thyroid is a rare developmental anomaly, presenting in the adult with obstructive symptoms during respiration, deglutition and speech. The main therapeutic issue after exact diagnosis is the restoration of thyroid function, and surgical intervention, when necessary, has to deal with problems related to the site and function of the ectopic gland. A case of a 25-year-old female with dyspnoea and dysphagia due to a 3 x 4 cm ectopic lingual thyroid, excised by an original peroral approach via a mandibular midline osteotomy, is reported. Our surgical technique is described and the diagnostic and therapeutic problems are reviewed.

Dual-site thyroid ectopy in a mother and son

We found familial thyroid ectopy in a mother and son, each of whom had an anterior neck mass corresponding to a perihyoid ectopic thyroid. In addition, technetium scintigraphy revealed another focus of aberrant uptake at their tongue roots. Neither patient showed hypothyroid symptoms or abnormal biochemical data other than a mildly elevated TSH level in the son. No other member of the family had a thyroid disorder. To our knowledge this is the first documented instance of familial thyroid ectopy in multiple sites. The observed similarity in distribution of ectopic tissue suggests a hereditary pathogenic factor.

Pituitary enlargement due to lingual thyroid gland and primary hypothyroidism

Pituitary enlargement can occur as a result of primary hypothyroidism. We present a newborn with pituitary enlargement and congenital hypothyroidism secondary to a lingual thyroid gland. Thyroid hormone therapy caused a regression of pituitary enlargement.

Ectopic thyroid: residual function after withdrawal of treatment in infancy and later childhood

Plasma thyroxine (T4) and thyrotrophin (TSH) were estimated in 34 children identified by neonatal hypothyroid screening and subsequently found to have ectopic thyroid tissue on isotope scan. Before treatment plasma T4 ranged from 8-143 nmol/l and TSH from 39-1,230 mU/l. After one week off treatment during their second year, repeat T4 in 26 of these cases showed a significant correlation with the pre-treatment values (r = 0.57). However, only 3 of the 5 children with pre-treatment T4 levels over 100 nmol/l at diagnosis had normal T4 values when retested. Similarly, when 10 children with pre-treatment T4 values over 65 nmol/l were retested off treatment at the ages of 5.8-8.2 years, only 4 had plasma T4 levels in the normal range. These results illustrate the wide range of thyroid function which can occur in children with ectopic thyroid tissue and indicate that some continue to have near-normal thyroid function for considerable periods. However, pre-treatment T4 results do not allow accurate identification of these latter cases.

Neonatal hypothyroidism: recent developments

This chapter summarizes recent developments in the field of sporadic congenital hypothyroidism (CH) and transient neonatal hypothyroidism detected by systematic neonatal thyroid screening. The incidence of CH detected by screening is about 1 in 4000 births in North America, Europe and Australia; it is lower (1 in 7000) in Japan. The aetiology remains unknown; genetic and environmental factors are possibly involved. The role of autoimmunity has recently been studied extensively. Antithyroglobulin (ATA) and antimicrosomal antibodies are not involved; the possible role of thyroid growth blocking antibodies (TGBAb) of maternal origin remains controversial. Evaluation of clinical signs, bone maturation, serum T4 and the position and size of the thyroid by scintigraphy at the time of diagnosis in CH infants are important because these variables are related to the final psychoneuro-intellectual prognosis, irrespective of the adequacy of therapy. Thyroid echography always distinguishes a normal thyroid in the neonate but cannot define precisely the type of thyroid dysgenesis, if present (e.g. ectopic, athyreosis). The determination of serum Tg contributes to the diagnosis but its specificity and sensitivity are insufficient to replace thyroid scintigraphy. Therapy by LT4, at an initial dose of 25-50 micrograms/day in full-term infants, is universally recommended. The objective of therapy is to reach as soon as possible and to maintain serum concentrations of total and free T4 at the upper limits of normal for age. Serum TSH should decrease as rapidly as possible below 20 microU/ml and then remain within the normal range. Persistent hyperthyrotropinaemia in spite of normal serum T4 has to be avoided as it could represent poor compliance and/or insufficient therapy. Programmes of 10 to 14 years of follow-up of CH infants have now shown that the neuropsychointellectual prognosis of CH is excellent in all cases when therapy and psychosocial environment are adequate. Although still within the normal range, IQ is somewhat lower in spite of appropriate therapy in cases of severe prenatal hypothyroidism and some transient and correctable neurological signs occasionally occur. In Western countries transient neonatal hypothyroidism is usually due to iodine deficiency or iodine excess; the newborn infant is hypersensitive to the antithyroid action of an extraphysiological supply of iodine. TSH binding inhibitor immunoglobulins (TBII) of maternal origin occasionally cause transient neonatal hypothyroidism. In developing countries with severe iodine deficiency and endemic goitre, the incidence of thyroid failure in the newborn can be as high as 1 in 10.(ABSTRACT TRUNCATED AT 400 WORDS)

Cretinism and lingual thyroid presenting in an adult

A 29 year old woman presented with menorrhagia secondary to hypothyroidism. Subsequent investigation confirmed the presence of a lingual thyroid. Features of cretinism were present despite the late presentation. This unusual case is discussed with reference to previous publications.

Preliminary results on the mental development of hypothyroid infants detected by the Quebec Screening Program

A prospective study of the mental development of hypothyroid infants detected by the Quebec Network for Genetic Medicine began in January, 1976. The mean age at initiation of thyroid hormone therapy was 27 days. Forty-five hypothyroid infants and 37 normal control subjects were assessed at age 12 months with the Griffiths mental development test; 77 and 41, respectively, were assessed at age 18 months, and 59 and 40, respectively, at 36 months. There were no statistically significant differences in the various test scores between the two populations at age 12 months, but at age 18 and 36 months the hypothyroid infants had lower scores in hearing-speech performance scales and practical reasoning (36 months) which also decreased their global quotient. The mean scores were still above 100 and only nine were below 85. Further assessment of the influence of early therapy on mental development at age 6 years is needed before definitive statements can be made about the long-term mental development in these subjects.

Growth, development, and reassessment of hypothyroid infants diagnosed by screening

Thirty]six neonates in whom hypothyroidism was diagnosed after thyroid stimulating hormone screening were reassessed at 1 year. All had grown satisfactorily and the mental development scores were normal in all except two. Treatment was withdrawn in 32 and persistent hypothyroidism was confirmed in 31 cases. Thyroid stimulating hormone concentrations were raised in one-third of cases before the withdrawal of treatment and this was associated with generally lower concentrations of serum thyroxine (T4) and smaller doses of L-thyroxine than in those cases with normal concentrations of thyroid stimulating hormone. In treating congenital hypothyroidism, serum T4 concentrations should be monitored regularly and the dose of thyroxine adjusted to maintain serum T4 in the upper part of the reference range.

Congenital hypothyroidism in Denmark

Among 436 959 live infants born between 1970 and 1975 in Denmark were 72 (49 girls and 23 boys) who developed primary hypothyroidism, giving an incidence of 1 in 6064 live births. In the oldest group (6 to 8 years of age) the incidence was 1 in 5100. The age at diagnosis ranged from 1 week to 5 years 4 months; 10% were diagnosed within the first month, 40% within the first 3 months, and 70% within the first year of life. Thyroid scintigrams were available for 43 patients, 72% had aplastic or hypoplastic thyroid glands, 12% had ectopic thyroid glands, 16% had goitres. Patients with aplastic or hypoplastic thyroids tended to be diagnosed earlier than those with ectopic thyroid glands. The calculated incidence in the presence study is lower than that suggested by the Danish neonatal screening programme.

Population screening for congenital hypothyroidism

A pilot screening programme for congenital hypothyroidism covering most of North London, Essex, Bedfordshire, and Hertfordshire entailed carrying out an assay of thyroid-stimulating hormone on single Guthrie dried blood spots. During one year 87 444 babies were screened and 26 cases of primary congenital hypothyroidism detected, giving an incidence of 1:3363. Only two cases (7.7%) had already been diagnosed on clinical grounds before the results of screening became available. In two other babies the diagnosis was delayed. The programme thus resulted in the early treatment of 22 babies, eight of whom already had pronounced features of hypothyroidism that had not been detected on routine clinical examinations. Although definitive evidence will not be available for some years, the results suggest that the prognosis for most of these babies is likely to be improved by early diagnosis; thus the introduction of national screening should be delayed no longer.