familial medullary thyroid carcinoma

Familial Medullary Thyroid Carcinoma (FMTC)

Familial medullary thyroid cancer (FMTC) is a rare form of thyroid cancer that accounts for less than 1% of all thyroid cancers. It is characterized by the development of medullary thyroid cancer, which forms in the inside of the thyroid gland.

Key Features:

• Inherited condition: FMTC is an inherited condition caused by mutations in the RET (rearranged during transfection) gene.
• Equal incidence in men and women: The incidence of FMTC is equal in men and women.
• Rare subtype of MEN2: FMTC is a rare subtype of Multiple Endocrine Neoplasia Type 2 (MEN2), a hereditary endocrine disorder.

Clinical Features:

• A neck lump or neck pain
• Diarrhea due to raised calcitonin levels

Additional Information:

• Most individuals with medullary thyroid cancer do not have an inherited form of the disease.
• FMTC is distinct from other forms of medullary thyroid cancer, which may be caused by mutations in the RET gene.

References:

[3] Familial medullary thyroid cancer is a rare form of thyroid cancer accounting for less than 1% of all thyroid cancers. Incidence is equal in men and women. [7] Familial medullary thyroid cancer (FMTC) is an inherited condition and a subtype of MEN2 (multiple endocrine neoplasia type 2), a hereditary endocrine ... [8] May 9, 2021 — It is characterized by the development of medullary thyroid cancer. FMTC is the result of mutations in the RET (rearranged during transfection) ...

Familial medullary thyroid carcinoma (FMTC) is a rare type of thyroid cancer that can be inherited in families. The signs and symptoms of FMTC are similar to those of sporadic medullary thyroid cancer, but may also include:

• A family history of thyroid cancer or other related conditions such as multiple endocrine neoplasia type 2 (MEN2) [12]
• A lump or nodule in the neck that can be felt through the skin [4][14]
• Swollen lymph nodes in the neck [1]
• Difficulty swallowing or breathing due to compression of the windpipe or esophagus by a large tumor [6][10]
• Hoarseness or changes in voice due to nerve invasion by the cancer [15]

It's worth noting that many people with FMTC may not experience any symptoms at all, and the disease can be detected through genetic testing even before symptoms appear. In fact, up to 25% of cases of medullary thyroid cancer are familial, meaning they can be passed down by family members [12].

Early detection and treatment of FMTC are crucial in preventing complications and improving outcomes. Surgery to remove the thyroid gland is often the main treatment for FMTC, and may be recommended even before symptoms appear if a person has a genetic predisposition [14].

Based on the provided context, it appears that there are several diagnostic tests available for familial medullary thyroid carcinoma (FMTC). Here's a summary of the relevant information:

• Imaging tests: Computerized tomography (CT) or magnetic resonance imaging (MRI) scans of the neck and body may be carried out to identify the nodule on the thyroid gland. [13]
• Molecular Genetics Tests: Various molecular genetics tests are available, including RNA analysis, sequence analysis of select exons, targeted variant analysis, deletion/duplication analysis, and sequence analysis. These tests can help detect genetic mutations associated with FMTC. [12]
• Calcitonin levels: Serum calcitonin levels are used for detection, staging, postoperative management, and prognosis in patients with FMTC. Elevated calcitonin levels can indicate the presence of cancer. [15]

It's worth noting that a diagnosis of medullary thyroid cancer (MTC) is typically made through a combination of clinical evaluation, imaging studies, and molecular genetics tests.

References:

[12] Context result 12 [13] Context result 13 [15] Context result 15

Treatment Options for Familial Medullary Thyroid Carcinoma (FMTC)

Familial medullary thyroid carcinoma (FMTC) is a rare and inherited form of thyroid cancer that can be challenging to treat. While there are no specific treatments approved exclusively for FMTC, the following drug therapies have shown promise in managing this condition:

• Tyrosine Kinase Inhibitors (TKIs): TKIs, such as Vandetanib and Cabozantinib, have been approved for use in progressive or metastatic medullary thyroid cancer (MTC) [1]. These drugs work by targeting the RET protein, which is often mutated in FMTC patients. Selpercatinib (Retevmo) and pralsetinib (Gavreto), two other TKIs, have also been approved for use in MTC [2].
• Targeted Therapies: Targeted therapies that act on changes in DNA found in some cases of FMTC are being explored. These treatments aim to specifically target the genetic mutations responsible for the disease [7].

Key Points

• Two FDA-approved drugs, Vandetanib and Cabozantinib, have been shown to be effective in managing advanced MTC, which may also benefit FMTC patients.
• TKIs, such as Selpercatinib and pralsetinib, have also demonstrated efficacy in treating MTC.
• Targeted therapies that address specific genetic mutations associated with FMTC are being investigated.

References

[1] SR Priya et al. (2017) - Two drugs, Vandetanib and Cabozantinib, have been approved for use in progressive or metastatic MTC [1]. [2] Aug 23, 2024 - Selpercatinib (Retevmo) and pralsetinib (Gavreto) are drugs known as RET inhibitors [2]. [7] Apr 28, 2022 - Targeted therapies that act on changes in DNA found in some cases of FMTC are being explored [7].

The differential diagnosis for familial medullary thyroid carcinoma (FMTC) includes several conditions that can present with similar symptoms and characteristics. Some of the key differential diagnoses for FMTC are:

• Medullary Thyroid Carcinoma (MTC): This is a distinct subtype of thyroid cancer that originates in the parafollicular C cells of the thyroid gland [8]. MTC can occur sporadically or as part of a familial syndrome, and it shares some similarities with FMTC.
• Hyperparathyroidism: This condition is characterized by an overproduction of parathyroid hormone, which can lead to hypercalcemia. Hyperparathyroidism is specifically associated with type 2A multiple endocrine neoplasia (MEN2A), a syndrome that includes FMTC [1].
• Multiple Endocrine Neoplasia Type 1 (MEN1): This is another rare genetic disorder that can affect the endocrine system, including the thyroid gland. MEN1 can present with a range of symptoms and conditions, including hyperparathyroidism and medullary thyroid carcinoma [5].

It's worth noting that FMTC is a distinct clinical entity that requires specific diagnostic criteria to be met. A diagnosis of FMTC typically involves the presence of three or more family members with non-medullary thyroid cancer in the absence of other known associated conditions [3].