Increasing interest in the treatment of locally advanced and already metastasized thyroid cancer is reflected in the high number of submitted and accepted conference papers at the annual meeting of the American Society of Clinical Oncology (ASCO Congress) 2011. Many patients suffering from differentiated, undifferentiated and medullary thyroid cancer do not respond to established therapeutic procedures, so that new strategies have to be developed. Targeted biological agents are a new and promising therapeutic method that selectively affects complex signaling cascades, especially angiogenesis, of the malignant cells. Clinicians and researchers should understand the potential of these therapeutic strategies and be aware of the typical side effects.