Multitargeted Kinase Inhibition in Metastatic Differentiated Radioiodine-Refractory Thyroid Cancer: A Look at New Therapeutic Options for a Rare Disease.
BACKGROUND
Metastatic differentiated thyroid cancer (DTC) is a rare disease that is in the first line treated with iodine-131 radioisotope therapy. Until recently, options were very limited in the case of progressive radioactive-iodine (RAI)-refractory disease. Based on new study results, tyrosine kinase inhibitors (TKIs) have attracted attention. The TKI sorafenib demonstrated significantly improved progression-free survival (PFS) in a phase III trial. Recent data from another phase III trial showed that the TKI lenvatinib achieved high response rates and a large improvement in PFS in metastatic RAI-refractory DTC patients in the first-line setting and after 1 prior line of TKI. However, little is known about the response to lenvatinib in patients pretreated with multiple lines of TKIs.


METHODS
We present the case of a 45-year-old man with metastatic RAI-refractory DTC progressing after multiple prior treatments with TKIs and chemotherapy. A very good and long-lasting response to lenvatinib was observed. Careful and prospective monitoring as well as management of side effects including dose adaptation were necessary to ensure success of treatment.


CONCLUSIONS
Here, we review different novel treatment options for patients with metastatic RAI-refractory DTC.
Onkologie, Kantonsspital Graubünden, Chur, Switzerland.
Katharina
K
Mischler
Stefan
S
Kneifel
Richard
R
Cathomas
D000970:Antineoplastic Agents / Q000008:administration & dosage; D004307:Dose-Response Relationship, Radiation; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D058990:Molecular Targeted Therapy / Q000379:methods*; D010671:Phenylurea Compounds / Q000008:administration & dosage*; D047428:Protein Kinase Inhibitors / Q000008:administration & dosage; D011804:Quinolines / Q000008:administration & dosage*; D019275:Radiopharmaceuticals / Q000627:therapeutic use; D035583:Rare Diseases; D013964:Thyroid Neoplasms / Q000175:diagnosis / Q000556:secondary* / Q000628:therapy*; D017211:Treatment Failure; D016896:Treatment Outcome
D000970:Antineoplastic Agents; D007457:Iodine Radioisotopes; D010671:Phenylurea Compounds; D047428:Protein Kinase Inhibitors; D011804:Quinolines; D019275:Radiopharmaceuticals; C531958:lenvatinib