Lenvatinib and selpercatinib successfully treated RET fusion gene-positive papillary thyroid carcinoma cardiac metastases: a case report

Background: Cardiac metastasis from thyroid cancer is rare and has an extremely poor prognosis. Although some patients who undergo heart surgery survive, the therapeutic effectiveness of systemic therapy is limited. Case Description: A 53-year-old woman with a history of papillary thyroid carcinoma (PTC) presented with cough and right chest discomfort. She underwent total thyroidectomy, followed by three rounds of radioactive iodine therapy, to treat pulmonary metastasis. Metastases to the lung, chest wall, liver, heart, and lymph nodes were observed on computed tomography. Core needle biopsy of the tumor in the right chest wall revealed the recurrence of PTC. Cardiac metastasis was discovered by echocardiography and cardiac magnetic resonance imaging, and blood test indicated a thyroglobulin level of 851 ng/mL. Based on the presence of cardiac metastasis and strong clinical symptoms, the condition was assumed to be fatal, and lenvatinib was started right away. Three weeks after starting lenvatinib, every metastatic lesion shrank. Once the ERC1-RET fusion gene was identified, we switched to selpercatinib therapy. Ten weeks after starting selpercatinib, every tumor shrank and blood thyroglobulin dropped to 68.1 ng/mL. Initial symptoms such as cough and right chest pain improved. Lenvatinib- and selpercatinib-related adverse effects can be managed with supportive care. Conclusions: To the best of our knowledge, this is the first case of successful systemic therapy for cardiac metastasis from PTC. Conventionally, cardiac surgery is the main treatment for cardiac metastasis, but now systemic therapy is also an important alternative.

Automated summary

This is a case report of cardiac metastasis from thyroid cancer. A 53-year-old female patient presented with cough and right chest discomfort. After examination, it was found that she had a history of papillary thyroid carcinoma, accompanied by metastasis in the lungs, chest wall, liver, heart, and lymph nodes. After surgery and radioactive iodine therapy, the disease still progressed. Finally, the treatment plan was determined through genetic testing, and lenvatinib and selpercatinib were used for systemic therapy, which achieved significant therapeutic effects. This case indicates that systemic therapy is one of the important treatment methods for cardiac metastasis.