Endocrine DOI 10.1007/s12020-013-0100-2
ENDOCRINE IMAGING
Lingual thyroid Anda Gonciulea • David S. Cooper Roberto Salvatori
•
Received: 18 October 2013 / Accepted: 22 October 2013 Ó Springer Science+Business Media New York 2013
Keywords Thyroid Lingual Ectopia Hypothyroidism
A 19-year female presented to the Johns Hopkins Endocrine Clinic to adjust her thyroid hormone replacement therapy. She had been diagnosed with a lingual thyroid at age 3 during a routine physical examination. At that time, she had multiple diagnostic tests, including imaging (likely including a radioactive iodine scan) that reportedly confirmed the lingual mass to be thyroid tissue. At the time of diagnosis, per her mother, thyroid function tests were normal. However, to prevent the lingual thyroid tissue from growing and causing compressive symptoms, the patient was placed on thyroid hormone replacement therapy. The dose was adjusted over the next 15 years, but the patient had stopped the medication about 1 month prior to the clinic visit. She had no symptoms of hypothyroidism or compressive or obstructive symptoms. At the time of the visit, serum TSH was elevated at 36.8 mU/L (0.5–4.5) with FT4 0.9 ng/dL (0.8–1.8) and total T3 of 107 ng/dL (76–181). Physical examination revealed an easily seen erythematous round mass at the base of her tongue (Fig 1). No palpable thyroid tissue was present in the pre-tracheal region. Imaging of the neck was not performed given the already established diagnosis. Lingual thyroid is a rare embryological abnormality that occurs in approximately 1:100,000 live births [1]. It is one
A. Gonciulea D. S. Cooper R. Salvatori (&) Division of Endocrinology, Diabetes, & Metabolism, Department of Medicine, The Johns Hopkins University School of Medicine, 1830 East Monument Street #333, Baltimore, MD 21287, USA e-mail: [email protected]
Fig. 1 Lingual thyroid evident as a round mass at the base of the tongue
of the possible thyroid ectopias (including thyroglossal cysts), caused by the failure of descent of the thyroid anlage and incomplete obliteration of its vertical tract between the third and seventh week of gestation [1]. While mutations in the transcription termination factor-2, PAX8, and in the TSH receptor genes have been reported in a minority of patients with thyroid dysgenesis, the etiopathogenesis of the majority of cases remains unclear. Lingual thyroid is 4–7 times more common in females. The majority of patients are asymptomatic, but obstructive symptoms such as dysphagia, dysphonia, and dyspnea may occur. Hypothyroidism may also develop, as it did in our patient, often first diagnosed during puberty, pregnancy, or menopause. Rarely, the lingual thyroid may cause hyperthyroidism [2], or be the site of thyroid cancer development [3]. In patients with suspected lingual thyroid, the work-up should always include thyroid function tests. The need for
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radioiodine thyroid scintigraphy and computerized tomography or magnetic resonance imaging remains debatable. A subset of patients requires surgical excision of the symptomatic mass, and, in the case of insufficient eutopic thyroid tissue or coexisting autoimmune thyroid disease, long-term thyroid hormone replacement. Conflict of interest The authors declare that they have no conflicts of interest.
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References 1. J.G. Batsakis, A.K. El-Naggar, M.A. Luna, Thyroid gland ectopias. Ann. Otol. Rhinol. Laryngol. 10, 996–1000 (1996) 2. M.P. Abdallah-Matta, P.H. Dubarry, J.J. Pessey, P. Caron, Lingual thyroid and hyperthyroidism: a new case and review of the literature. J. Endocrinol. Invest. 25, 264–267 (2002) 3. R.E. Massine, S.J. Durning, T.M. Koroscil, Lingual thyroid carcinoma: a case report and review of the literature. Thyroid 11, 1191–1196 (2001)
ENDOCRINE IMAGING
Lingual thyroid Anda Gonciulea • David S. Cooper Roberto Salvatori
•
Received: 18 October 2013 / Accepted: 22 October 2013 Ó Springer Science+Business Media New York 2013
Keywords Thyroid Lingual Ectopia Hypothyroidism
A 19-year female presented to the Johns Hopkins Endocrine Clinic to adjust her thyroid hormone replacement therapy. She had been diagnosed with a lingual thyroid at age 3 during a routine physical examination. At that time, she had multiple diagnostic tests, including imaging (likely including a radioactive iodine scan) that reportedly confirmed the lingual mass to be thyroid tissue. At the time of diagnosis, per her mother, thyroid function tests were normal. However, to prevent the lingual thyroid tissue from growing and causing compressive symptoms, the patient was placed on thyroid hormone replacement therapy. The dose was adjusted over the next 15 years, but the patient had stopped the medication about 1 month prior to the clinic visit. She had no symptoms of hypothyroidism or compressive or obstructive symptoms. At the time of the visit, serum TSH was elevated at 36.8 mU/L (0.5–4.5) with FT4 0.9 ng/dL (0.8–1.8) and total T3 of 107 ng/dL (76–181). Physical examination revealed an easily seen erythematous round mass at the base of her tongue (Fig 1). No palpable thyroid tissue was present in the pre-tracheal region. Imaging of the neck was not performed given the already established diagnosis. Lingual thyroid is a rare embryological abnormality that occurs in approximately 1:100,000 live births [1]. It is one
A. Gonciulea D. S. Cooper R. Salvatori (&) Division of Endocrinology, Diabetes, & Metabolism, Department of Medicine, The Johns Hopkins University School of Medicine, 1830 East Monument Street #333, Baltimore, MD 21287, USA e-mail: [email protected]
Fig. 1 Lingual thyroid evident as a round mass at the base of the tongue
of the possible thyroid ectopias (including thyroglossal cysts), caused by the failure of descent of the thyroid anlage and incomplete obliteration of its vertical tract between the third and seventh week of gestation [1]. While mutations in the transcription termination factor-2, PAX8, and in the TSH receptor genes have been reported in a minority of patients with thyroid dysgenesis, the etiopathogenesis of the majority of cases remains unclear. Lingual thyroid is 4–7 times more common in females. The majority of patients are asymptomatic, but obstructive symptoms such as dysphagia, dysphonia, and dyspnea may occur. Hypothyroidism may also develop, as it did in our patient, often first diagnosed during puberty, pregnancy, or menopause. Rarely, the lingual thyroid may cause hyperthyroidism [2], or be the site of thyroid cancer development [3]. In patients with suspected lingual thyroid, the work-up should always include thyroid function tests. The need for
123
Endocrine
radioiodine thyroid scintigraphy and computerized tomography or magnetic resonance imaging remains debatable. A subset of patients requires surgical excision of the symptomatic mass, and, in the case of insufficient eutopic thyroid tissue or coexisting autoimmune thyroid disease, long-term thyroid hormone replacement. Conflict of interest The authors declare that they have no conflicts of interest.
123
References 1. J.G. Batsakis, A.K. El-Naggar, M.A. Luna, Thyroid gland ectopias. Ann. Otol. Rhinol. Laryngol. 10, 996–1000 (1996) 2. M.P. Abdallah-Matta, P.H. Dubarry, J.J. Pessey, P. Caron, Lingual thyroid and hyperthyroidism: a new case and review of the literature. J. Endocrinol. Invest. 25, 264–267 (2002) 3. R.E. Massine, S.J. Durning, T.M. Koroscil, Lingual thyroid carcinoma: a case report and review of the literature. Thyroid 11, 1191–1196 (2001)
