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Medullary thyroid carcinoma

Updated : March 13, 2024





Background

This type of thyroid cancer arises from the parafollicular cells or C cells of the thyroid gland. Calcitonin is produced by medullary thyroid carcinoma, and a high calcitonin level is a crucial characteristic of this malignancy. It is derived from the neural crest-originating medullary C cells.

Recent developments in molecular aetiology and genetic testing have resulted in patient risk stratification and the identification of molecular therapeutic targets.

Patients having mutations that place them at a high risk should undergo preventative thyroidectomy. Multiple tyrosine kinase inhibitors are licensed for the treatment of progressive, metastatic medullary thyroid carcinoma.

Epidemiology

Between 4%-10% of all thyroid malignancies in the US are medullary carcinomas. Generally, the incidence of sporadic medullary thyroid carcinoma peaks when individuals are in their 40s or 50s, whereas when associated with MEN2B or MEN2A, the highest incidence is in the 2nd or 3rd decade.

Anatomy

Pathophysiology

In contrast to the typically unilateral medullary thyroid cancer related to sporadic MEN syndromes, the medullary thyroid cancer linked to various MEN syndromes is typically multicentric and bilateral.

Because C cells exist largely in the higher regions of the thyroid gland, these tumours typically affect the upper regions of both lobes. In addition to producing hormones including corticotropin, serotonin, prostaglandins, and melanin, paraneoplastic disorders such as Cushing syndrome and carcinoid syndrome can manifest as medullary thyroid cancer.

Etiology

Most medullary thyroid cancers are idiopathic, and only around 20%-25% are due to inherited disorders such as familial medullary thyroid cancer, MEN 2A and MEN 2B. RET mutations in thyroid neural crest tissue can result in the development of medullary thyroid cancer.

MEN2 and FMTC medullary thyroid tumours are linked to alterations in the germline. Approximately 40%-50% of medullary thyroid tumours of the sporadic origin have RET mutations.

Genetics

Prognostic Factors

The prognosis of medullary thyroid cancer is dependant on three main factors:

  • Age
  • Grade of tumor
  • Status of surgical resection

5-year survival rates for the first 3 grades of the tumor is extremely favourable at 93%, but stage 4 tumors only have a survival rate of 28%.

Clinical History

Physical Examination

Age group

Associated comorbidity

Associated activity

Acuity of presentation

Differential Diagnoses

Laboratory Studies

Imaging Studies

Procedures

Histologic Findings

Staging

Treatment Paradigm

by Stage

by Modality

Chemotherapy

Radiation Therapy

Surgical Interventions

Hormone Therapy

Immunotherapy

Hyperthermia

Photodynamic Therapy

Stem Cell Transplant

Targeted Therapy

Palliative Care

Medication

 

pralsetinib 

400

mg

Orally 

every day


Continue until the illness progresses or intolerable toxicity occurs



 

pralsetinib 

Age: > 12 years:

400

mg

orally

every day


Continue until the illness progresses or intolerable toxicity occurs



 

Media Gallary

References

https://www.ncbi.nlm.nih.gov/books/NBK459354/

Medullary thyroid carcinoma

Updated : March 13, 2024




This type of thyroid cancer arises from the parafollicular cells or C cells of the thyroid gland. Calcitonin is produced by medullary thyroid carcinoma, and a high calcitonin level is a crucial characteristic of this malignancy. It is derived from the neural crest-originating medullary C cells.

Recent developments in molecular aetiology and genetic testing have resulted in patient risk stratification and the identification of molecular therapeutic targets.

Patients having mutations that place them at a high risk should undergo preventative thyroidectomy. Multiple tyrosine kinase inhibitors are licensed for the treatment of progressive, metastatic medullary thyroid carcinoma.

Between 4%-10% of all thyroid malignancies in the US are medullary carcinomas. Generally, the incidence of sporadic medullary thyroid carcinoma peaks when individuals are in their 40s or 50s, whereas when associated with MEN2B or MEN2A, the highest incidence is in the 2nd or 3rd decade.

In contrast to the typically unilateral medullary thyroid cancer related to sporadic MEN syndromes, the medullary thyroid cancer linked to various MEN syndromes is typically multicentric and bilateral.

Because C cells exist largely in the higher regions of the thyroid gland, these tumours typically affect the upper regions of both lobes. In addition to producing hormones including corticotropin, serotonin, prostaglandins, and melanin, paraneoplastic disorders such as Cushing syndrome and carcinoid syndrome can manifest as medullary thyroid cancer.

Most medullary thyroid cancers are idiopathic, and only around 20%-25% are due to inherited disorders such as familial medullary thyroid cancer, MEN 2A and MEN 2B. RET mutations in thyroid neural crest tissue can result in the development of medullary thyroid cancer.

MEN2 and FMTC medullary thyroid tumours are linked to alterations in the germline. Approximately 40%-50% of medullary thyroid tumours of the sporadic origin have RET mutations.

The prognosis of medullary thyroid cancer is dependant on three main factors:

  • Age
  • Grade of tumor
  • Status of surgical resection

5-year survival rates for the first 3 grades of the tumor is extremely favourable at 93%, but stage 4 tumors only have a survival rate of 28%.

pralsetinib 

400

mg

Orally 

every day


Continue until the illness progresses or intolerable toxicity occurs



pralsetinib 

Age: > 12 years:

400

mg

orally

every day


Continue until the illness progresses or intolerable toxicity occurs



https://www.ncbi.nlm.nih.gov/books/NBK459354/