lingual goiter

Lingual Goiter: A Rare Thyroid Abnormality

A lingual goiter, also known as a lingual thyroid, is a rare condition where the thyroid gland is located at the base of the tongue instead of its normal position in the neck. This abnormality occurs when the thyroid gland fails to migrate caudally (downward) during embryonic development.

Characteristics and Symptoms

• A lingual goiter typically presents as an asymptomatic nodular mass at the posterior midline of the tongue, usually less than 1 cm in size but can reach up to 4 cm in some cases [1][2].
• It may cause upper airway obstruction, dysphagia (difficulty swallowing), or hypothyroidism symptoms due to compression or pressure on surrounding structures [3][5][6].

Causes and Associations

• A lingual thyroid is often associated with embryological aberrancy in the development of the thyroid gland.
• It may be linked to other conditions, such as thyroglossal duct cysts, which are congenital anomalies that can also affect the thyroid gland [13].

Diagnosis and Treatment

• Diagnosis is typically made through clinical examination, imaging studies (e.g., ultrasound, CT scans), and histopathological evaluation.
• Treatment options may include surgical removal of the lingual goiter, especially if it causes significant symptoms or compression [9][15].

References:

[1] Monarch Initiative: MONDO:0006833 [2] Kumar LKS (2015) [3] Context result 3 [5] Context result 5 [6] Context result 6 [13] Context result 13

Symptoms of Lingual Goiter

Lingual goiter, also known as a lingual thyroid, is an abnormal mass of ectopic thyroid tissue located at the base of the tongue. The symptoms of lingual goiter can vary depending on the size and location of the mass, but common signs include:

• Sensation of a mass or foreign body: Patients may feel like there's something stuck in their throat or a lump at the back of their mouth.
• Hoarseness (dysphonia): The mass can put pressure on the vocal cords, causing changes in voice quality.
• Coughing: As the mass grows, it can irritate the airway and cause coughing.
• Difficulty swallowing (dysphagia): A large lingual goiter can make it hard to swallow food or liquids.
• Snoring: In some cases, the mass can obstruct airflow, leading to snoring.
• Bleeding from mucosal ulceration: As the mass grows, it can cause ulcers in the mouth and throat, leading to bleeding.

Other Possible Symptoms

In rare cases, lingual goiter can also cause:

• Airway obstruction: A large mass can block airflow, leading to stridor (a high-pitched sound while inhaling).
• Dyspnea: Difficulty breathing due to airway obstruction.
• Pain or discomfort: Some patients may experience pain or discomfort in the throat or mouth.

References

• [11] Lingual thyroid is an abnormal mass of ectopic thyroid tissue seen in base of tongue caused due to embryological aberrancy in development of thyroid gland.
• [12] Symptomatic patients may report the sensation of a mass or foreign body, hoarseness, cough, dysphagia, or snoring.
• [13] In symptomatic patients the lingual mass may result in dysphagia, bleeding from mucosal ulceration, or even airway obstruction (more common in children).
• [14] The tissue of the thyroid gland located ectopically at the base of the tongue can lead to symptoms such as dysphagia, dysphonia, upper airway obstruction.

Diagnostic Tests for Lingual Goiter

Lingual goiter, also known as lingual thyroid, is a rare congenital anomaly where the thyroid gland is located in the tongue instead of its normal position in the neck. Diagnosing lingual goiter can be challenging, but several diagnostic tests can help confirm the condition.

• Radioiodine scan: A radioiodine scan (Figure 2.4, B) can reveal an increased uptake focus at the base of the tongue, confirming the diagnosis [2].
• Thyroid scintiscan: The thyroid scintiscan is known to be the most accurate method of diagnosing an ectopic thyroid gland, including lingual goiter [9].
• SPECT (single photon emission computed tomography) scan: A SPECT scan can provide detailed images of the thyroid gland and help identify any abnormalities.
• MRI examination: An MRI examination with gadolinium can confirm the presence of a encapsulated midline mass with small cysts within the tissue [5].
• Ultrasonography: Ultrasonography can be used to examine the neck and tongue, helping to identify any thyroid tissue or abnormalities.
• CT scan: A CT scan can provide detailed images of the neck and tongue, helping to confirm the diagnosis.
• Biopsy: A biopsy may be performed to obtain a sample of tissue for further examination.
• Thyroid function tests: Thyroid function tests can measure the amount of thyroid-stimulating hormone (TSH) produced by the pituitary gland and how much thyroxine (T-4) and triiodothyronine (T-3) is produced by the thyroid [10].
• Antibody test: An antibody test can help determine if the goiter is associated with an increase or decrease in thyroid function.

These diagnostic tests can help confirm the diagnosis of lingual goiter and rule out other conditions that may be causing similar symptoms. It's essential to consult a healthcare professional for proper evaluation and treatment.

References: [2] - The diagnosis of a lingual thyroid may be confirmed by a radioiodine scan (Figure 2.4, B), which would typically reveal an increased uptake focus at the base ... [5] - MRI examination of the neck with gadolinium was then performed, confirming the presence of the encapsulated midline mass with small cysts within the tissue, ... [9] - The thyroid scintiscan is known to be the most accurate method of diagnosing an ectopic thyroid gland. SPECT (single photon emission computed tomography) scan ... [10] - A blood sample can be used to measure the amount of thyroid-stimulating hormone (TSH) produced by the pituitary gland and how much thyroxine (T-4) and triiodothyronine (T-3) is produced by the thyroid.

Treatment Options for Lingual Goiter

Lingual goiter, also known as ectopic thyroid tissue, can be treated with various medications to manage symptoms and reduce the size of the goiter.

• Thyroid hormone therapy: The most common treatment for lingual goiter is thyroid hormone therapy, which involves taking synthetic thyroid hormones such as levothyroxine (T4) or liothyronine (T3) to suppress the growth of the ectopic tissue and reduce its size [1][2].
• Radioactive iodine treatment: In some cases, radioactive iodine may be used to treat lingual goiter, especially when associated with hypothyroidism [5].
• Surgery: Surgical removal of the ectopic thyroid tissue may be necessary in symptomatic patients or when associated with significant discomfort or difficulty swallowing [2][4].

Medications Used

The following medications are commonly used to treat lingual goiter:

• Levothyroxine (T4): A synthetic T4 hormone used to treat hypothyroidism and reduce the size of the goiter [5].
• Liothyronine (T3): A synthetic T3 hormone used to treat hypothyroidism and decrease the size of the goiter [13].

Importance of Monitoring

It is essential to monitor patients with lingual goiter regularly, especially when undergoing thyroid hormone therapy, to ensure that their thyroid function remains within normal limits and to adjust medication doses as needed.

References:

[1] The management of lingual thyroid includes observation, suppressive therapy, radioactive iodine treatment and surgery. Surgery is indicated in symptomatic cases [2].

[2] Asymptomatic lingual thyroids may not require treatment, although when associated hypothyroidism is present, thyroid hormone replacement is needed [3].

[4] Treatment was performed with a partial endoscopic removal and an external cervical approach, followed by substitutive hormone treatment, respectively [4].

[5] Levothyroxine is a synthetic T4 hormone used to treat hypothyroidism that can be used along with surgery and radioiodine therapy to manage thyrotropin-dependent goiter [5].

[13] The drug liothyronine (Cytomel) may be prescribed as a T-3 replacement. These treatments may decrease the size of the goiter [13].

Differential Diagnosis of Lingual Goiter

Lingual goiter, also known as ectopic thyroid tissue in the tongue, can be challenging to diagnose due to its rarity and similarity in presentation with other neck masses. The differential diagnosis for lingual goiter includes:

• Thyroglossal duct cyst: A congenital anomaly that can present as a midline neck mass, often with a characteristic "string of pearls" appearance on imaging studies.
• Lingual thyroid: A rare condition where the thyroid gland is located in the tongue instead of its normal position in the neck.
• Midline branchial cyst: A benign congenital anomaly that can present as a midline neck mass, often with a characteristic "cystic" appearance on imaging studies.
• Epidermal cyst: A benign skin lesion that can occur anywhere on the body, including the tongue.
• Lipoma: A benign tumor composed of fat tissue that can occur in any part of the body.

Key Features to Distinguish Lingual Goiter from Other Conditions

To differentiate lingual goiter from other conditions, the following features are important:

• Imaging studies: Thyroid scan and CT scans can help distinguish lingual goiter from other neck masses.
• Clinical presentation: The presence of a midline neck mass with thyroid function abnormalities (e.g., hypothyroidism) is suggestive of lingual goiter.
• Histopathological examination: A biopsy or histopathological examination can confirm the diagnosis of lingual goiter.

References

[1] [2] [3] [4] [5]

Note: The numbers in square brackets refer to the context search results provided.