Medullary Thyroid Cancer

Disclaimer:
This blog is for informational purposes only and should not be taken as medical advice. Content is sourced from third parties, and we do not guarantee accuracy or accept any liability for its use. Always consult a qualified healthcare professional for medical guidance.

What is Medullary Thyroid Cancer?

Medullary Thyroid Cancer (MTC) arises from parafollicular C-cells producing calcitonin, comprising 3-5% of thyroid cancers. It’s sporadic (75%) or hereditary (25%, linked to RET mutations in MEN2 syndromes). MTC is aggressive, metastasizing early to lymph nodes, liver, lungs, or bones. In 2025, ~1,000 US cases annually, median age 50, equal in genders.

Symptoms

Symptoms include neck lump, hoarseness, difficulty swallowing/breathing, persistent cough, diarrhea (from calcitonin excess), flushing, and weight loss. Advanced MTC causes bone pain or fractures from metastases. Hereditary cases may have associated pheochromocytoma or hyperparathyroidism symptoms.

Causes

Sporadic MTC links to RET mutations (40-60%), radiation, and age. Hereditary from germline RET mutations in MEN2A/2B or FMTC. In 2025, NGS identifies RET alterations for therapy.

Diagnosis

Diagnosis uses ultrasound for nodules, fine-needle biopsy with calcitonin staining, blood tests (calcitonin, CEA), and genetic testing for RET. Imaging (CT, MRI, PET) stages metastases. In 2025, AI ultrasound improves detection.

Treatment

Surgery (total thyroidectomy + lymph node dissection) is primary, curative for localized. Advanced uses TKIs (vandetanib, cabozantinib for RET-wild, selpercatinib for RET-mutant). Radiation palliates. In 2025, immunotherapy trials show promise.

Future Outlook

In 2025, 5-year survival is 90% localized, 40% distant. RET inhibitors improve advanced survival to 60%. By 2030, gene therapies could achieve 70% for advanced.

Sources

Cleveland Clinic’s “Medullary Thyroid Cancer: Symptoms & Treatment” for symptoms; Mayo Clinic’s “Medullary thyroid cancer – Symptoms and causes” for causes; NCI’s “Thyroid Cancer Treatment” for treatment; PMC’s “Medullary Thyroid Carcinoma: Update on Diagnosis and Treatment” for updates; OncoDaily’s “Medullary Thyroid Cancer: Symptoms, Diagnosis, Treatment” for overview; Endocrine Society’s “Medullary Thyroid Carcinoma” for genetics; Thyroid’s “Advances in Medullary Thyroid Carcinoma” for advancements; UCSF Health’s “Medullary Thyroid Cancer” for prognosis; Memorial Sloan Kettering’s “Medullary Thyroid Cancer” for care; Healthline’s “Medullary Thyroid Cancer: Causes, Symptoms, Diagnosis” for details.