Pharmacotherapy options for advanced thyroid cancer: a systematic review

Poor prognosis of anaplastic thyroid cancer and advanced disease in differentiated and medullary thyroid cancer, together with absence of effective therapeutic measures, has induced recent intensified basic and clinical research in this area. The aim of this article is to assess the effects of new drug treatment for advanced thyroid cancer. We searched MEDLINE and EMBASE until the end of September 2011 for relevant data. Further sources were reference lists of original publications and review articles. We included prospective studies that investigated drug interventions for advanced thyroid cancer published in any language. We did not include trials solely communicated as abstracts. For inclusion, studies had to report overall survival, progression-free survival or similar, or response outcomes. Data were extracted by one author and checked by the other. All tables are part of this publication. Because only non-comparative studies were included, we had to focus on descriptive analysis. Twenty-four studies with 715 patients were included; 18 studies investigated kinase inhibitors, the remainder various drugs. All studies reported response (only one complete response was observed; proportions of partial response were up to 49%). Median progression-free survival was about 12 months, ranging from 3.7 to 27.9 months. Adverse events (at least grade 3) of kinase inhibitors included hypertension, hand foot syndrome and diarrhoea (10%, 16% and 9%, respectively). Due to bias-prone data, any interpretation of newer pharmacotherapy options for advanced thyroid cancer is limited because only non-comparative studies could be included. Therefore, we strongly argue the need for adequate randomized controlled trials that should provide a better basis for therapeutic decision making in thyroid cancer.