Sorafenib Stops Growth of Thyroid Cancer When Radioactive Iodine Has Stopped Working

ASCO Annual Meeting
June 2, 2013

In a recent study, researchers found that the drug sorafenib (Nexavar) keeps metastatic differentiated thyroid cancer from worsening when treatment with radioactive iodine has stopped working. Differentiated thyroid cancer is the most common type of thyroid cancer; it is called “differentiated” because the cancerous thyroid cells look like normal thyroid cells when viewed under a microscope. Metastatic cancer means the thyroid cancer has spread outside of the thyroid.

Thyroid cancer is generally successfully treated with surgery and radioactive iodine. However, about 5% to 15% of patients develop radioactive iodine resistance, meaning that this treatment stops working. For these patients, the drug doxorubicin (Adriamycin) is the standard treatment option, but it does not work well and causes many side effects. Sorafenib is a type of targeted treatment, which is a treatment that targets the cancer’s specific genes, proteins, or the tissue environment that contributes to cancer growth and survival, and is in the form of a tablet that is taken orally (by mouth).

As part of this study, 417 patients with metastatic, radioactive iodine-resistant differentiated thyroid cancer received either sorafenib or a placebo (an inactive treatment, often called a “sugar pill”). However, once the disease worsened, patients taking a placebo could switch to treatment with sorafenib. Researchers found that it took nearly 11 months for the disease to worsen for those taking sorafenib, compared with almost six months for those receiving the placebo. They also found that 42% of patients receiving sorafenib did not have their disease worsen for six months or longer. In addition, about 12% of patients taking sorafenib had their tumors shrink, compared with less than 1% of those taking the placebo.

What this means for patients

“After having no effective drugs for these patients for so many years, it is very exciting to find an oral drug that stops cancer growth for several months,” said Marcia Brose, MD, PhD, Assistant Professor of Otolaryngology and Head and Neck Surgery in the Abramson Cancer Center and the Perelman School of Medicine at the University of Pennsylvania in Philadelphia. “For these patients, a longer time before the disease worsens means more months without hospitalization and invasive procedures to control the symptoms.” Sorafenib is currently approved by the U. S. Food and Drug Administration for other types of cancer, but not thyroid cancer, so it may not be available for all patients; talk with your doctor for more information.

Dr. Brose was a recipient of a Conquer Cancer Foundation of ASCO Young Investigator Award in 2000.

Questions to Ask Your Doctor

  • What type of thyroid cancer do I have?
  • What treatments have I already received?
  • What treatment plan do you recommend?
  • Is my current treatment still working to control thyroid cancer growth?
  • If not, what other treatment options are available to me?
  • What clinical trials are open to me?
  • What are the risks and benefits of the recommended treatment plan?

For More Information

Guide to Thyroid Cancer

Understanding Targeted Treatments

ASCO Expert Corner: Placebos in Cancer Clinical Trials