Dr. Kunadharaju and Dr. Goyal are house officers in the Department of Internal Medicine, and Dr. Silberstein is a professor and chief of hematology/oncology, all at CHI Creighton University Medical Center in Omaha,Nebraska. Dr. Rudraraju is a house officer at MacNeal Hospital in Berwyn, Illinois. Dr. Silberstein is also chief of oncology at the VA Nebraska-Western Iowa Healthcare System in Omaha.
References
were diarrhea, stomatitis, hand and foot syndrome, hypertension, and abdominal pain. Although uncommon, clinically significant AEs also included fistula formation and osteonecrosis of the jaw.
Summary
Patients with progressive or symptomatic metastatic disease who are not candidates for surgery or radiotherapy should be considered for TKI therapy. Though not curative, TKIs can only stabilize disease progression. Initiation of TKIs should be considered in rapidly progressive disease, because these drugs are associated with considerable AEs affecting the quality of life (QOL).
Patients who progressed or were unable to tolerate vandetanib or cabozantinib can choose to participate in clinical trials with investigational multitarget inhibitors. Other alternatives include pazopanib, sunitinib, and sorafenib, which finished phase 2 trials and showed some partial responses. 29,52-57 If patients are unable to tolerate MKIs, they can try conventional chemotherapy consisting of dacarbazine with other agents or doxorubin. 58-60
Conclusions
Molecular targeted therapy is an emerging treatment option for patients with metastatic thyroid cancer (Table 2). The authors suggest that such patients participate in clinical trials in the hope of developing more effective and tolerable drugs and recommend oral TKIs for patients with rapidly progressive disease who cannot participate in a clinical trial. For patients who cannot tolerate or fail one TKI, the authors recommend trying other TKIs before initiating cytotoxic chemotherapy.
Before initiation of treatment for metastatic disease, an important factor to consider is the pace of disease progression. Patients who are asymptomatic and have the very indolent disease may postpone kinase inhibitor therapy until they become rapidly progressive or symptomatic, because the AEs of treatment will adversely affect the patient’s QOL. In patients with symptomatic and rapidly progressive disease, initiation of treatment with kinase inhibitor therapy can lead to stabilization of disease, although at the cost of some AEs. More structured clinical trials are needed, along with an evaluation of newer molecular targets for the management of this progressive metastatic disease with a dismal prognosis.
Author disclosures The authors report no actual or potential conflicts of interest with regard to this article.
Disclaimer The opinions expressed herein are those of the authors and do not necessarily reflect those of Federal Practitioner, Frontline Medical Communications Inc., the U.S. Government, or any of its agencies. This article may discuss unlabeled or investigational use of certain drugs. Please review complete prescribing information for specific drugs or drug combinations—including indications, contraindications, warnings, and adverse effects—before administering pharmacologic therapy to patients.
