What is pediatric GIST?

Patients who were diagnosed with GIST at 18 years of age or less will have the diagnosis of pediatric GIST.

A patient diagnosed at age 19 must be thinking, but I have to be closer to a pediatric patient rather than an adult type patient. Probably so, but we would have encountered a similar problem for any age. If we had chosen 23, a 24 year old would have asked the same question. For now, we ask that young adult patients, who do not meet the criteria of pediatric GIST, do not concern themselves with the exact definition.

We believe that there is a distinction between pediatric GIST and adult GIST. There seem to be differences in both the clinical course and the biology between younger and older patients. The purpose of the Pediatric and wildtype GIST clinic at the NIH is to better define these differences. We are examining a more rigorous definition of pediatric GIST in two ways.

First, by accepting all young patients with GIST into the clinic, we will be able to determine the clinical course of patients of all ages, over an extended period of time. This will put us in position to assess if there is an age determinant to clinical course.

Second, as we acquire more biological samples from patients, researchers will be able to determine the differences in the makeup of tumor samples at the DNA/RNA/protein levels. Patients with similar RNA makeup can then be grouped together and the ages of the patients in these distinct groups can be examined. This will allow us to determine if there is a cutoff age other than 18 that better distinguishes pediatric, wildtype and adult GIST.

These are two ways by which we can assess if clinical and biological studies confirm our age distinction between pediatric and adult GIST. In time, we may have seen enough patients to be able to make further distinctions, such as: infant/toddler, pre-teen, adolescent, young adult and adult type GIST.