Considering the fact that the prognosis of ATRT is much worse than other high-grade brain tumors and needs more intensified chemoradiation therapy (14), and since divergent differentiations in this tumor can mislead pathologists (11), this study assessed the role of INI1 IHC in the diagnosis of ATRT in Shiraz Province patients, southern Iran. Here, SMARCB1 is linked to brain neoplasm.