Like adult GIST, pediatric GIST can be further divided into subgroups. The most familiar and perhaps the most common type does not seem to have a distinct name so let’s just call it “Pediatric GIST.” It most commonly affects girls between the ages of about 6 to 18 and almost always starts in the stomach.
The second well-known type of GIST affecting young people is called “Carney’s Triad.” It is named after Dr. J. Aidan Carney who first described it in 1977. Patients with Carney’s Triad may have several different types of tumors including GIST, pulmonary chondroma, and/or functioning extra-adrenal paraganglioma. If any two of these tumors are present, a diagnosis of the “triad” can be made, particularly if age and sex factors are supportive.
In 2002, Dr. Carney and Dr. Constantine Stratakis reported on a new syndrome that was similar to, yet distinct, from Carney’s triad. They had found 12 patients in 5 families with two parts of the “triad,” paraganglioma and GIST. Since this condition appeared to be inheritable and the “true Carney’s Triad” did not, Carney and Stratakis concluded that this syndrome was different than Carney’s Triad and called it “Familial Paraganglioma and Gastric Stromal Sarcoma” (also known as Carney-Stratakis Syndrome). The patients varied in age from 9 to 46 years old at diagnosis with 9 of the 14 patients under the age of 23.
When looking at multiple medical reports, it appears like there may be one more type of pediatric GIST. The youngest GIST patients of all may be born with GIST and need surgery soon after birth. This type of GIST, called “neonatal or congenital GIST”, appears to affect both boys and girls (although girls are more common) and seems to start in the intestines instead of the stomach. We found 6 cases described as GIST in newborns, however there seems to be some doubt about whether or not these are really leiomyosarcomas or GISTs.