PDGFRA and gastrointestinal stromal tumor: In the absence of mutations in KIT or PDGFRA it is also important to look for mutations in BRAF, a rare, but important finding from a treatment perspective, since BRAF inhibitors are available, and also in NF1. Patients with neurofibromatosis, who have a germline mutation in NF1, are at increased risk of GIST and this finding may indicate occult neurofibromatosis.