KIT and gastrointestinal stromal tumor: Tarn et al identified a young patient who developed a GIST at the age of 37 and was found to carry the same germline pathogenic variant as our patient, KIT exon 11 (p.Asp579del).21 In this case, the patient’s tumor had a high mitotic index and was classified as high risk but had a clinical indolent disease which remained stable on imatinib.21