PMEL and ependymoma: IHC is often positive for EMA but negative for HMB-45 and Melan-A.[13] The shape of melanotic schwannoma cells is mild and arranged in a palisade shape, which can be seen in areas A and B, but negative for HMB-45 and Melan-A.[14] In addition, it needs to be distinguished from ependymoma, ganglioglioma, medulloblastoma, and other tumors, which are relatively easy to distinguish according to histological characteristics and IHC phenotype.