Which patient with thyroid cancer deserves systemic therapy and when?

Area of Science:

• Oncology
• Endocrinology
• Nuclear Medicine

Background:

• Distant metastases from differentiated thyroid cancer (DTC) occur in less than 10% of patients.
• Approximately 50% of these patients are refractory to radioiodine (RAI) therapy, facing a poor prognosis with a 10-year survival rate under 10%.

Purpose of the Study:

• To discuss the challenges in identifying RAI-refractory differentiated thyroid cancer.
• To review the role and timing of tyrosine kinase inhibitors (TKIs) in managing RAI-refractory DTC.

Main Methods:

• Review of clinical trial data and literature on differentiated thyroid cancer treatment.
• Analysis of outcomes for patients treated with radioiodine (RAI) and tyrosine kinase inhibitors (TKIs).

Main Results:

• Tyrosine kinase inhibitors (TKIs) like sorafenib and lenvatinib have shown objective response rates and improved progression-free survival in RAI-refractory DTC.
• No overall survival benefit has been demonstrated yet for TKIs in this patient population.

Conclusions:

• Defining the criteria for RAI-refractory differentiated thyroid cancer is crucial.
• Optimal timing for initiating TKI therapy in RAI-refractory DTC remains a significant clinical challenge.