New Treatment for Drug-Resistant GIST

Gastrointestinal Cancers Symposium
January 18, 2011

In a new study on gastrointestinal stromal tumor (GIST), researchers found that the drug sorafenib (Nexavar) is an effective treatment when imatinib (Gleevec) and/or sunitinib (Sutent) no longer work. GIST is a rare tumor that begins in the gastrointestinal tract, such as the stomach or small bowel. It often has a mutation (change) in either the KIT or PDGFRA gene, which contributes to its growth and spread. Drugs that help block these mutations, called targeted therapies, are the most common treatment options. The standard first treatment (called the first-line treatment) is imatinib, but most patients develop a resistance, meaning the treatment stops working and the tumor begins to grow and spread. After imatinib stops working, patients often receive sunitinib, a similar targeted therapy, but this drug can stop working as well. This study was developed to find another treatment option when imatinib and sunitinib no longer work.

Researchers gave sorafenib to six patients who had GIST that was resistant to imatinib and 32 who had GIST that was resistant to imatinib and sunitinib. Sorafenib is another similar targeted therapy but it blocks more mutations, including those that develop in GIST tumors that become resistant to imatinib and sunitinib. While taking sorafenib, 13% of patients had their tumors shrink and 68% had tumor growth slow or stop (called stable disease). After one year, 44% of the patients were alive, and after two years, 21% of patients were alive. The side effects of sorafenib were more severe, including high blood pressure and a condition called hand-foot syndrome which causes dry, peeling skin. Many (63%) of the patients needed to have the dose lowered because of side effects; however, the drug was still effective at lower doses.

What this means for patients

“These results give us hope that we can find additional treatment options for patients with GIST,” said senior author Hedy Kindler, MD, Associate Professor of Medicine at the University of Chicago. There are very few treatment options for people with drug-resistant GIST. For the patients in this study, sorafenib was able to keep GIST from getting worse when imatinib and/or sunitinib no longer worked.

What to ask your doctor

  • What are my treatment options for GIST?
  • If the first treatment stops working, what other treatment options do I have?
  • What clinical trials are open to me?

For More Information

Guide to Gastrointestinal Stromal Tumor (GIST)

Understanding Targeted Treatments

Hand-Foot Syndrome