OBJECTIVES: Explore epidemiology and drug treatment of radioactive iodine-refractory differentiated thyroid cancer (RR-DTC) in EU5. METHODS: Epidemiology of RR-DTC was derived from the Kantar Health (KH) CancerMPact database, sources for which include country specific cancer registries, published scientific studies and proprietary physician surveys comprising 81 doctors seeing a total  of 3,985 patients per month.  Data specific to treatment of RR-DTC was derived from patient chart review studies conducted by KH. Age and gender specific incidence rates, annual stage specific progression rates and annual stage specific survival rates are used to calculate total number of surviving patients at a specific stage up to 10 years after diagnosis. RESULTS: Incidence of thyroid cancer ranged between 5 - 20 per 100K population across EU-5 (UK-4.8, Germany-8.4, France-13.4, Italy-20.3, Spain-7.2). Among all thyroid patients, % DTC showed less variation: 76% (UK), 83% (Germany), 87% Italy, 88% (Spain), 91% (France). Among DTC, % RR was very similar (range 26% - 33%).  Among RR DTC, 23% received watch and wait,  33% non-systemic management and 44% systemic therapy.  Among those receiving systemic therapy, 48% received chemotherapy, 46% received tyrosine kinase inhibitors (TKI) and 6% BRAF inhibitors.  Among those receiving chemotherapy, 50% received doxorubicin, either as monotherapy or part of a multi drug regimen and 20% received cisplatin.  Among those receiving a TKI, 51% received sorafenib, 28% sunitinib.   CONCLUSIONS: Among RR DTC patients treated with systemic therapy, chemotherapy and TKIs are used most often.   The most common chemotherapy is a doxorubicin containing regimen and sorafenib is the most common TKI used.