**3.3. Wild-type GIST**

Approximately 12–15% of adult GIST and 90% of pediatric GIST do not have KIT and PDGFRA mutations [33]. Wild-type (WT) GISTs comprise GISTs that arise in NF1, Carney-Stratakis syndrome, and Carney triad [4]. WT GISTs may have other forms of mutations. BRAF V600E substitution has been described in 7–13% of WT GISTs [35, 36]. About 30% of WT GISTs are SDH deficient and occur solely in the stomach. They mainly affect children and young adults and have a variation in their nature from being indolent to progressive [4].
