ESMO 2020: Multikinase Inhibitors for Asymptomatic Radioiodine-Refractory Thyroid Cancer
Posted: Friday, October 9, 2020
Although multikinase inhibitors prolong progression-free survival in patients with asymptomatic radioactive iodine–refractory differentiated thyroid cancer, there is no consensus on when systemic treatment should be initiated in this population. The RIFTOS MKI study, presented during the European Society for Medical Oncology (ESMO) Virtual Congress 2020 (Abstract 1918P), “provides baseline characteristics and treatment practices for patients with asymptomatic radioactive iodine–refractory differentiated thyroid cancer under real-life conditions,” explained Marcia S. Brose, MD, PhD, of the Abramson Cancer Center of the University of Pennsylvania, Philadelphia, and colleagues.
The global, noninterventional study enrolled 656 patients with asymptomatic radioactive iodine–refractory differentiated thyroid cancer to evaluate the outcomes of patients treated with and without multikinase inhibitors at study entry. The median patient age was 67 years, and 45% of participants were male. The most frequent histology type was papillary (74%), and most patients were radioactive iodine–refractory due to the lack of radioactive iodine uptake (64%). Almost all patients (91%) had metastatic disease at the time of enrollment.
The median time from the diagnosis of initial differentiated thyroid cancer to enrollment in the study was 6.7 years. Overall, 205 patients (31%) received sorafenib, and the median duration of sorafenib exposure was 13.1 months. One-third of patients received another multikinase inhibitor during the study, most often lenvatinib (30%).
Safety data from patients treated with sorafenib were consistent with sorafenib’s known safety profile; 181 patients (88%) had at least one adverse event, and 68 (33%) had one or more serious adverse events. The authors noted that a hand-foot skin reaction, reported in 42% of patients who received sorafenib, seemed to be noted less frequently in real-life practice than in phase III clinical trials. The effectiveness results of the RIFTOS MKI study will be forthcoming.
Disclosure: For full disclosure of the study authors, visit esmo.org.