A ganglion‐rich gastrointestinal stromal tumor: A case report

We report a case of an extremely rare type of duodenal gastrointestinal stromal tumor (GIST) that included neuronal components. Although gastrointestinal autonomic nerve tumors (GANTs), a subtype of GISTs, exhibit ultrastructural features of the nerve plexus, neuronal cells have not been observed within GANTs or GISTs. GISTs originate from interstitial cells of Cajal (ICCs), which are markedly different from the progenitor cells of neural elements and neural‐crest‐derived stem cells. This may explain why GISTs typically lack neuronal elements. It remains unclear that the neuronal components of this tumor are neoplastic or hyperplastic, but proliferation and survival of ICCs have recently been reported to be closely related to neurons. Although we could not find the KIT, PDGFR , and BRAF mutation as far as we examined, it may have had a rare mutation in NF1 , a fusion of EVT6‐NTRK3 , or an as‐yet‐unknown KIT mutation that affected neurogenesis. Further investigation of related genetic mutations and accumulation of data from other similar cases is needed.