Heart failure as first sign of development of cardiac metastases in a patient with diagnosis of papillary thyroid carcinoma on treatment with tyrosine-kinase inhibitors: differential diagnoses and clinical management.

BACKGROUND: Cardiac metastases from papillary thyroid carcinoma are very uncommon. Their incidence is rising due to improvements in survival and diagnosis; nevertheless, our patient is the fourth case reported up to date. There are no clinical trials available in this scenario. Therefore, treatment choice is made based on clinical experience and case reports; notably, the largest case report series was prior to the approval for using tyrosine-kinase inhibitors in thyroid cancer. PATIENT: A 73-year-old lady had dedifferentiated papillary thyroid cancer with ongoing sorafenib. After 9 months on this treatment, she presented with dyspnea and heart failure. Differential diagnosis included infection, progression of disease and cardiotoxicity. After a comprehensive assessment (echocardiography, computed tomography, PET, magnetic resonance), we found progression of lung disease, and the appearance of heart metastases. RESULTS: After recovering from the basal status, she started on second-line treatment with sunitinib, which was well-tolerated. She achieved stable disease with a decrease in tumor marker levels. CONCLUSIONS: We should include cardiac metastases in the differential diagnosis of heart failure in cancer patients. Magnetic resonance imaging is the gold standard for assessment. Sorafenib is the mainstay of the first-line therapy in metastatic thyroid cancer, achieving long-term disease control with good tolerance. Sunitinib could be a safe second-line treatment option (not cardiotoxicity related) with promising results. Therefore, our report presents a sequence of treatment with tyrosine-kinase inhibitors in metastatic thyroid carcinoma with an encouraging outcome, which deserves further investigation.