At the recent American Society of American Oncology Meeting (ASCO), Dr. George Demetri, Director of the Center for Sarcoma and Bone Oncology, Dana-Farber Cancer Institute, Boston, presented results from a collaborative trial that indicates in a long-term follow-up a 22% survival rate for advanced GIST.
According to Dr. Demetri, “A significant fraction of patients can survive for more than 10 years with imatinib (Gleevec) as their initial therapy for advanced GIS; and for almost half as their only systemic therapy for advanced GiST, understanding the pathobiology of these exceptional outcomes will be important to understanding the disease better.”
The trial was initiated after the 1998 discovery by Japanese investigators of gain-of-function mutations in the gene encoding for KIT kinase.
The phase III Southwest Oncology Group (SWOG) Intergroup S0033 trial launched in 2000. The trial featured 746 patients with metastatic or unresectable GIST. Patients were randomly assigned to receive daily imatinib at a dose of either 400 mg or 800 mg (400 mg twice daily). Patients in the 400-mg qd group had the option of crossing over to the 800-mg dose at the time of disease progression, and 130 patients chose to do so.
