Management of Sporadic Medullary Thyroid Carcinoma (MTC)

Surgery to remove the thyroid and dissection of cervical nodal compartments is the mainstay of management of MTC.

Total thyroidectomy is the treatment of choice for patients with MTC because of the high incidence of multicentricity, the more aggressive course, and the fact that 131I therapy is usually not effective.

The NCCN guidelines for MTC are outlined in Figure 1.

MTCs are also characterized by high rates of nodal metastases.

• Patients with unilateral intrathyroidal tumors are reported to have lymph node metastases in 81% of central compartment (level VI) dissections, 81% of ipsilateral lateral compartment (levels II to V) dissections, and 44% of contralateral lateral compartment (levels II to V) dissections.

• Similar numbers are reported for patients with bilateral tumors.

• In addition, the incidence of lateral neck nodal disease depends on the frequency of metastases in the central compartment.

• Preoperative neck ultrasonography and basal calcitonin / CEA levels may also be used to define the extent of nodal metastases and hence guide surgery, although this is controversial.

  • Patients with basal calcitonin levels less than 20 pg/mL are unlikely to have nodal metastases.

  • Increasing calcitonin levels are associated with metastases to the ipsilateral central and lateral neck ( > 20 pg/mL), contralateral central neck ( > 50 pg/mL), contralateral lateral neck ( > 200 pg/mL), and upper mediastinum ( > 500 pg/mL).

    • As such, biochemical cure can be achieved in patients with preoperative calcitonin levels less than 1000 pg/mL but is unlikely in patients with levels greater than 10,000 pg/mL.

The current ATA guidelines recommend that patients without nodal metastases on ultrasonography and no distant disease undergo a total thyroidectomy and bilateral level VI node dissection.

• In this scenario, no consensus was reached regarding the optimal management of the lateral compartments, and the guidelines indicate that a prophylactic lateral neck dissection may be considered based on calcitonin levels.

• In contrast, the NCCN guidelines suggest considering a prophylactic ipsilateral modified neck dissection for high-volume or gross disease in the adjacent central neck if the tumor is greater than or equal to 1 cm in size or the disease is bilateral.

• In patients with known lymph node metastases (but no distant disease), total thyroidectomy, bilateral level VI dissection, and dissection of levels II to V in the involved compartment are recommended.

  • Prophylactic dissection of the contralateral neck can be considered if the calcitonin level is greater than 200 pg/mL.

 

Rodrigo Arrangoiz MS, MD, FACS is an expert in the management of thyroid diseases and is a member of Sociedad Quirúrgica S.C at the America British Cowdray Medical Center.

Training:

• General surgery:

• Michigan State University:

• 2004 al 2010

• Surgical Oncology / Head and Neck Surgery / Endocrine Surgery:

• Fox Chase Cancer Center (Filadelfia):

• 2010 al 2012

• Masters in Science (Clinical research for health professionals):

• Drexel University (Filadelfia):

• 2010 al 2012

• Surgical Oncology / Head and Neck Surgery / Endocrine Surgery:

• IFHNOS / Memorial Sloan Kettering Cancer Center:

• 2014 al 2016