KIT and gastrointestinal stromal tumor: In our case, the diagnostic IHC panel served multiple crucial functions: (1) confirmation of neural crest origin through diffuse S-100 and SOX-10 positivity, (2) exclusion of GIST through negative CD117 and DOG-1 staining, and (3) exclusion of smooth muscle neoplasms through negative desmin and SMA staining [13].