Endocrine Abstracts

Introduction: TKIs including anti-VEGF receptor activity have been approved for the treatment of patients with radioiodine resistant thyroid carcinomas. For lenvatinib arterial thromboembolic events are listed as adverse events of special interest. In the phase III study of SELECT trial, arterial thromboembolic events were reported in 3% of lenvatinib-treated patients and 1% in the placebo group. Most of the patients had predisposing factors. Only one myocardial infarct was reported in the lenvatinib phase III study.

Patient: We report a 67 year-old-female with metastatic folicular thyroid carcinoma at time of diagnosis (bone, hepatic, lung and renal metastasis). Total thyroidectomy was performed. Zolendronate was started and radiotherapy was administired due to spinal cord compression caused by metastasis on L3, L4, L5. NO radioidine therapy was administired as it was considered radioiodine resistant (No RAI uptake) and treatment with Sorafenib was started. Sorafenib treatment resulted in disease progression with appearence of new hepatic and lung metastasisso treatment with sorafenib was discontinued and Lenvatinib was started with partial response. During further treatment with lenvatinib with dose reduction from initially 24 to 10 mg at 6 months of lenvatinib treatment a myocardial infarction occurred after 9 months of lenvatinib treatment. Coronary angiographydid not show significant coronary stenosis or structure abnormalities and echocardiography showed normal results with preserved ejection fraction. Treatment with lenvatinib was discontinued at the time of diagnosis of the myocardial infarction. Except for well controlled hypertension there were neither predisposing diseases like diabetes nor symptoms of cardiac ischemia on exertion

Conclusion: Our case report suggests that lenvatinib should also be added to the list of TKIs with ATE potential. So far, most of the thromboembolic events appeared after short-term treatment median duration of 10.8 months with tyrosine kinase inhibitors and mostly in patients with predisposing factors. However, our patient suffered from her first myocardial infarction aftertreatment with lenvatinib for 9 months, in absence of predisposing diseases except well controlled hypertension. Therefore, as previously proposed by Conti et al. for other TKIs also patients with lenvatinib treatment should be assessed for cardiovascular risk and coronary ischemia before and during the treatment