creation date: 2025-12-08 23:36
tags: PathologiesIncomplete
Medullary Thyroid Carcinoma
Background
Definitions
Thyroid cancer is a malignancy of the thyroid parenchymal cells. The parenchyma consist of two major cell types which give rise to various variants of thyroid cancer.
The predominant thyroid cancer is differentiated thyroid cancer which accounts for 90-95% of cases.
Parafollicular or C-cells give rise to medullary thyroid carcinoma (MTC) which accounts for 1-2%.
Etiology
Pathogenesis
Clinical Presentation
Signs & Symptoms
MTC typically presents as a sporadic solitary thyroid nodule in the upper portion of each thyroid lobe.
In most patients, metastases has already occur at time of diagnosis:
- Cervical lymph node involvement
- Upper aerodigestive tract compression or invasion causing dysphagia or hoarseness
Owing to its neuroendocrine nature, systemic symptoms may occur due to secretion of calcitonin:
- Diarrhea
- Facial flushing
- Ectopic Cushing syndrome (if tumours secrete corticotropin)