The use of receptor tyrosine kinase inhibitors in metastatic differentiated thyroid carcinoma
Anastasios Gkountouvas1, Ifigenia Kostoglou-Athanassiou1, Eirini Veniou1, Dimitrios Thomas1, Anastasia Aggelopoulou1, Marios Nikas1, Nicolaos Ziras2 & Philippos Kaldrymides1
The management of metastatic differentiated thyroid carcinoma included until recently the use of therapeutic 131I, radiotherapy and in specific cases chemotherapy. However, recently new agents entered in the management of differentiated metastatic thyroid carcinoma which aim at specific cell receptors and inhibit the growth of the carcinoma in a specific and targeted way.
The aim was to present the experience of the use of the receptor tyrosine kinase inhibitors, sorafenib and sunitinib in patients with advanced metastatic differentiated thyroid carcinoma.
Patients and methods: A group of 9 patients with advanced metastatic differentiated thyroid carcinoma after subtotal thyroidectomy and 131I therapy were studied. Within this group 4 patients had metastatic papillary, 3 had metastatic Hurthle cell thyroid carcinoma, 1 had follicular with pulmonary metastases at diagnosis and 1 had insular thyroid carcinoma. Sorafenib or sunitinib or sequentially sorafenib and sunitinib were administered, when progressive disease was observed after all other methods for the management of thyroid carcinoma had been applied.
Results: All patients had partial remission of the disease or stable disease, none of them entering full remission. Thyroglobulin decreased in all patients. The reduction in the volume of the neoplastic disease was from zero to significant. The patients have been followed up on therapy with the receptor tyrosine kinase inhibitors for a period of 7 to 17 months. Adverse reactions included gastrointestinal disturbances, diarrhea, hand foot syndrome, alopecia, hemorrhagic tendency, stomatitis and yellow skin discoloration. In patients already having a mild blood marrow suppression further suppression was observed, improving with diminishing drug dosage. Within this group of patients 3 had secondary loss of response to sorafenib after administration for a 4-month period and then sunitinib was administered.
Conclusion: The use of receptor tyrosine kinase inhibitors is a significant progress in the treatment of advanced metastatic thyroid carcinoma.