From the Guidelines
The optimum management of medullary thyroid carcinoma in multiple endocrine neoplasia type 2 (MEN 2) is total thyroidectomy with bilateral central neck dissection (level VI), as recommended by the most recent and highest quality study 1. This approach is necessary because medullary thyroid carcinoma in MEN 2 patients is typically multifocal and has a high propensity for early lymph node metastasis. Total thyroidectomy ensures complete removal of all thyroid tissue, eliminating the risk of leaving behind microscopic foci of cancer that would be missed with a lobectomy approach. The bilateral central neck dissection addresses the high likelihood of cervical lymph node involvement, even in cases where it may not be clinically apparent. This comprehensive surgical management is often performed prophylactically in MEN 2 patients identified through genetic testing, ideally before the age of 5 for MEN 2A and even earlier for the more aggressive MEN 2B variant. Some key points to consider in the management of medullary thyroid carcinoma in MEN 2 include:
- The importance of genetic testing to identify patients at risk for MEN 2 and medullary thyroid carcinoma
- The need for prophylactic total thyroidectomy in patients with certain RET mutations, such as those associated with MEN 2A and MEN 2B
- The role of bilateral central neck dissection in reducing the risk of lymph node metastasis
- The importance of regular monitoring of calcitonin and carcinoembryonic antigen levels to detect any disease recurrence
- The need for lifelong thyroid hormone replacement therapy after surgery. Radioactive iodine and conventional radiotherapy are ineffective for medullary thyroid carcinoma because these tumors arise from parafollicular C cells, which do not concentrate iodine like follicular-derived thyroid cancers, as noted in 1. Overall, the management of medullary thyroid carcinoma in MEN 2 requires a comprehensive and multidisciplinary approach, including genetic testing, prophylactic surgery, and regular monitoring for disease recurrence.
From the Research
Optimum Management of Medullary Thyroid Carcinoma in MEN 2
The optimum management of medullary thyroid carcinoma in multiple endocrine neoplasia type 2 (MEN 2) involves:
- Total thyroidectomy, which is the recommended surgical approach for patients with MEN 2, especially for those with a high risk of developing medullary thyroid carcinoma 2, 3, 4, 5
- The timing of total thyroidectomy depends on the specific RET mutation, age of the patient, and calcitonin levels 2, 4, 5
- Extensive lymph node dissection may be necessary for patients with cervical and upper mediastinal lymph node metastasis 2, 3, 4
Key Considerations
- Early diagnosis and treatment are crucial for improving outcomes in patients with MEN 2-associated medullary thyroid carcinoma 2, 6, 3, 4, 5
- Genetic screening and testing can help identify patients at high risk of developing medullary thyroid carcinoma, allowing for prophylactic thyroidectomy 2, 6, 4, 5
- The prognosis for patients with MEN 2-associated medullary thyroid carcinoma is generally better than for those with sporadic medullary thyroid carcinoma, especially if treated early 3, 5
Surgical Approaches
- Total thyroidectomy with or without radical neck dissection is the most appropriate surgical approach for patients with MEN 2-associated medullary thyroid carcinoma 2, 3, 4, 5
- Thyroid lobectomy and cervical lymphadenectomy may not be sufficient for patients with MEN 2, as multicentric disease is common in these patients 3
- Radioactive iodine and radiotherapy are not typically used in the treatment of medullary thyroid carcinoma, as they are not effective against this type of cancer 2, 6, 3, 4, 5