Protein Kinase Inhibitor Therapy in Advanced Thyroid Cancer: Ethical Challenges and Potential Solutions

Abstract

Protein kinase inhibitors (PKIs) have emerged as highly promising therapies in progressive metastatic radioiodine-refractory differentiated thyroid cancer and in medullary thyroid cancer; two were recently approved in the USA for use in medullary thyroid cancer (vandetanib, cabozantinib), and another for use in progressive metastatic radioiodine-refractory differentiated thyroid cancer (sorafenib). Although more than 90% of thyroid cancer patients fare well in response to conventional treatment, PKI therapy has the potential to provide benefit. Nonetheless, PKIs produce numerous side effects, may worsen quality of life, may hasten mortality (by 1–2%), require discerning clinical acumen, are not yet proven to improve thyroid cancer survival and are very costly. This raises questions about who should prescribe PKIs, and about whether their use in thyroid cancer is truly beneficent and ethically justified. Restraint should be exercised in their use in thyroid cancer, with potential risks and benefits carefully weighed and solutions devised to help ameliorate many of the problems associated with their use.

Keywords:

• beneficence
• distributive justice
• TKI
• tyrosine kinase inhibitor

Acknowledgements

The authors are indebted to C Kostelec for administrative assistance and to M Smith (Mayo Clinic, Rochester, MN, USA) for defining average retail US drug prices as indicated in Table 1. This article was presented in part at the 2013 Annual Meeting of the American Thyroid Association, San Juan, Puerto Rico, 16–20 October 2013.

Financial & competing interests disclosure

The authors have no 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. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties. No writing assistance was utilized in the production of this manuscript.