Gender-based Impact on Safety and Efficacy of Lenvatinib in Patients With Differentiated Thyroid Cancer

Lenvatinib is an orally available potent inhibitor of the split-kinase family of transmembrane growth factor receptors including Flt-1/VEGFR-1 and KDR/VEGFR. Lenvatinib has been investigated in hepatocellular carcinoma and in RAI-resistant thyroid cancer (Phase III trials) and in other malignancies, showing high rates of activity. In RAI-resistant thyroid cancer, lenvatinib showed a remarkable response rate over placebo (65% vs 2), combined with a prolonged progression free survival (18.3 vs 3.6 months). It has been approved for the treatment of locally recurrent or metastatic, progressive RAI resistance-DTC in the United States, Europe, and Japan, based on the results from SELECT trial. Moreover, lenvatinib demonstrated a meaningful clinical activity (response rate 64.8% in treatment arm vs 1.5% in placebo arm, p<0.001;) significantly reducing the tumour burden, with a median maximum percentage change in tumour size of -42.9%. Response was mostly pronounced at the first assessment (median -24.7% at 8 weeks after randomization) but it has been observed even in the following months (-1.3% per month). Recently, the efficacy of lenvatinib was confirmed in specific patient population, such as elderly. Although the efficacy is remarkable toxic effects are considerable and not all patients have the same risk to benefit ratio from lenvatinib treatment. Results derived from controlled clinical trials are rarely replicable in the real-life because these trials are usually conducted in selected populations, in a highly controlled setting, optimized to show the effect of the drug.

In this context growing evidences are showing gender associated functions playing a role in cancer incidence, progression and response to therapy; gender disparities in toxicities and effectiveness of certain drugs used in the treatment of the most common cancer is already well known.The aim of the present study is to evaluate the safety and efficacy profile of Lenvatinib based on gender in patients with refractory iodine DTC.

Inclusion criteria

• Patients with refractory iodine DTC treated with lenvatinib
• Signed written informed consent

Exclusion criteria

• Age < 18 years