The recent World Health Organisation (WHO) Classification of Tumours of the Central Nervous System 2021 categorises primary pineal parenchymal tumours as: pineocytomas, pineal parenchymal tumours of intermediate differentiation (PPTID), pineoblastoma, papillary tumour of the pineal region and desmoplastic myxoid tumour of the pineal region, SMARCB1-mutant (2). The gene discussed is SMARCB1; the disease is neoplasm.