title: Advances in chemotherapy of differentiated epithelial and medullary thyroid cancers.
abstract: BACKGROUND
  Systemic chemotherapies for advanced or metastatic thyroid carcinomas have been of only limited effectiveness. For patients with differentiated or medullary carcinomas unresponsive to conventional treatments, novel therapies are needed to improve disease outcomes.
  
  
  METHODS
  The PubMed and Google Scholar search engines were used to identify publications and peer-reviewed meeting presentations addressing chemotherapy and targeted therapy for differentiated or medullary carcinoma.
  
  
  RESULTS
  Multiple novel therapies primarily targeting angiogenesis have entered clinical trials for metastatic thyroid carcinoma. Partial response rates up to 30% have been reported in single agent studies, but prolonged disease stabilization is more commonly seen. The most successful agents target the vascular endothelial growth factor receptors, with potential targets including the mutant kinases associated with papillary and medullary oncogenesis. Two drugs approved for other malignancies, sorafenib and sunitinib, have had promising preliminary results reported, and are being used selectively for patients who do not qualify for clinical trials. Randomized trials for several agents are underway that may lead to eventual drug approval for thyroid cancer.
  
  
  CONCLUSIONS
  Treatment for patients with metastatic or advanced thyroid carcinoma now emphasizes clinical trial opportunities for novel agents with considerable promise. Alternative options now exist for use of tyrosine kinase inhibitors that are well tolerated and may prove worthy of regulatory approval for this disease.
authors.affiliation: Department of Endocrine Neoplasia and Hormonal Disorders, Division of Internal Medicine, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77230-1402, USA. sisherma@mdanderson.org
authors.forename: Steven I
authors.initials: SI
authors.lastname: Sherman
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D018276:Carcinoma, Medullary / Q000188:drug therapy*; D006801:Humans; D018160:Receptors, Cytoplasmic and Nuclear / Q000187:drug effects; D013964:Thyroid Neoplasms / Q000188:drug therapy*
chemical_list: D000970:Antineoplastic Agents; D018160:Receptors, Cytoplasmic and Nuclear