Written by Becky Bensenhaver

The Consortium for Pediatric and Wildtype GIST Research, coordinated by Dr. Lee Helman of the National Institute of Health (NIH) in Bethesda, Maryland, convened in Bethesda, Maryland, on June 13.

The Clinic is a collaboration between clinicians and researchers to collect data, investigate and develop treatment for Gastrointestinal Stromal Tumor patients who do not have either c-KIT or Platelet -Derived Growth Factor Receptor alpha (PDGFRA) mutations. This includes patients with Carney’s Triad, Carney- Stratakis Dyad, and Wildtype GIST. These tumors frequently stain negatively for a protein called Succinate Dehydrogenase, a condition referred to as being Succinate Dehydrogenasedeficient (SDH-deficient). There are currently three clinical trials in development for this population.

The first treatment study is being conducted by Dr. Margaret von Mehren in partnership with the Sarcoma Alliance through Research and Collaboration (SARC). This trial will utilize OSI-906, an insulin-like growth factor inhibitor (IGF-1R). IGF-1R is highly expressed in Pediatric and many adult Wildtype GISTs. Initial trial recruitment will be at Fox Chase Cancer Center in Philadelphia, Pennsylvania, with hopes of expansion to multiple clinical institutions in the future.

The second treatment study will utilize a drug called Vandetanib, an inhibitor of vascular-endothelial growth factor (VEGF) and endothelial growth factor receptor (EGFR). The efficacy rationale is based on the response of a type of kidney cancer bearing a genetic mutation similar to SDH-mutant GIST. This study will open initially at the NIH in Bethesda. If results are promising, additional trial accrual sites will be added.

The third treatment study is designed specifically to help understand how to administer Sutent to younger people who have GIST and to better understand how well it works. Dr. Katherine Janeway from the Dana-Farber Cancer Institute will supervise this trial.

Although Sutent has previously been used to treat Pediatric and Wildtype GISTs, neither OSI-906 nor Vandetanib have. As it is not yet known which of the treatments will prove most efficacious, the trial designs allow patients to participate without sequence restriction.

As treatments are becoming available, the NIH Pediatric and Wildtype GIST Clinic is transitioning from being held every six months to once a year. The hope is that patients will be receiving treatments through trial participation and will be seen at the various institutions for ongoing follow up.