LAUSR

Abstract Background Differentiated thyroid cancer (DTC) is the commonest endocrine cancer in Malaysia. Chemotherapy and radiotherapy has limited role in managing radioactive iodine (RAI)-refractory DTC. With the understanding of the molecular profiling of DTC, various novel therapies have been developed. Lenvatinib is a multiple kinase inhibitor (MKI) with promising activities based on the randomized phase III SELECT trial. Our study was to evaluate the safety and efficacy of lenvatinib a real live experience in patients with metastatic RAI-refractory DTC from University Malaya Medical Centre. Methods RAI-refractory DTC patients with progressive disease and with good performance status (0-2) were screened and treated with lenvatinib at UMMC from November 2014 to April 2017 with Eisai Named Patient Assisted Programme (NPAP) and the data was collected and analysed. Data collection was ended on June 2018. Results There were 23 patients with a median of 65 years (31-76) were enrolled. The male: female ratio was 1:1. All patients had prior thyroid surgery with history of at least once RAI treatment. Only 2 patients (8.7%) had prior therapy with sorafenib. Commonest sites of metastases were lung and bones. 47% of patients showed positive clinical response and 8.7% showed radiological response and 82.6% has biochemical response. Median overall survival (OS) was not ready to be calculated, and median progression free survival (PFS) was 23.9 months. Common adverse events (AE) observed in all grades were hypertension (87.0%), fatigue (95.7%), proteinuria (69.6%), skin reactions (52.2%) and diarrhoea (43.5%). Almost all cases had dose interruptions and reductions due to AE and it was done within initial 2 months of therapy. 26.7% of patients are still on the treatment. Conclusions Lenvatinib is a new treatment option with significant clinical benefit for patients with metastatic RAI-refractory DTC. It has significant adverse events but manageable toxicity with dose interruptions.