Treating Medullary Thyroid Cancer in the Age of Targeted Therapy

Abstract

Medullary thyroid carcinoma (MTC) is a rare neuroendocrine tumor deriving from the thyroid parafollicular cell. Thyroidectomy continues to serve as the primary initial treatment for this cancer. Because standard cytotoxic chemotherapy has proven ineffective, reoperation and external beam radiation therapy had been the only tools to treat recurrences or distant disease. The discovery that aberrant activation of RET, a receptor tyrosine kinase, is a primary driver of MTC tumorigenesis led to clinical trials using RET-targeting tyrosine kinase inhibitors. The successes of those trials led to the approval of vandetanib and cabozantinib for treating patients with progressive or symptomatic MTC. The availability of these drugs, along with additional targeted therapies in development, requires a thoughtful reconsideration of the approach to treating patients with unresectable locally advanced and/or metastatic progressive MTC.

Keywords:

• adverse events
• cabozantinib
• tyrosine kinase inhibitor
• vandetanib

Acknowledgements

The authors would like to thank Sarah Bronson, associate scientific editor from the department of scientific publications at MD Anderson Cancer Center for her editorial assistance.

Financial & competing interests disclosure

ME Cabanillas has served on the Exelixis advisory board and has received research funding and consulting fees from Exelixis. MI Hu has received research funding from AstraZeneca Pharmaceuticals. Supported by the NIH/NCI under award number P30CA016672. C Jiminez, EG Grubbs and GJ Coter have nothing to disclose. The University of Texas MD Anderson Cancer Center is supported in part by the National Institutes of Health through Cancer Center Support Grant CA16672. Supported by the NIH/NCI under award number P30CA016672. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.