Familial medullary thyroid cancer

Familial Medullary Thyroid Cancer (FMTC) is a type of thyroid cancer that is inherited in an autosomal dominant manner. It is characterized by the development of medullary thyroid carcinoma (MTC) in multiple family members. Unlike other forms of hereditary thyroid cancer, FMTC does not involve other endocrine glands.

Etiology

FMTC is caused by mutations in the RET proto-oncogene, which is located on chromosome 10. The RET gene is involved in the development of certain types of nerve cells, including those found in the thyroid gland. Mutations in this gene can lead to the uncontrolled growth and division of cells, resulting in the formation of a tumor.

Clinical Features

The primary clinical feature of FMTC is the development of medullary thyroid carcinoma. This type of cancer originates from the parafollicular cells (or C cells) of the thyroid gland, which produce the hormone calcitonin. Symptoms of MTC can include a lump in the neck, difficulty swallowing, hoarseness, and persistent cough.

Diagnosis

Diagnosis of FMTC is based on a combination of clinical findings, family history, and genetic testing. Genetic testing can identify mutations in the RET gene that are associated with FMTC. In addition, measurement of calcitonin levels in the blood can aid in the diagnosis of MTC.

Treatment

The primary treatment for FMTC is surgical removal of the thyroid gland (thyroidectomy). In some cases, nearby lymph nodes may also be removed. Following surgery, patients may require lifelong treatment with thyroid hormone replacement therapy.

Prognosis

The prognosis for individuals with FMTC varies and depends on several factors, including the age at diagnosis, the extent of the disease at the time of diagnosis, and the specific RET mutation present.

See Also

• Medullary thyroid cancer
• Thyroid cancer
• RET proto-oncogene
• Autosomal dominant