Favourable Response of Unresectable Giant Pinealoblastoma After Induction Chemotherapy and Craniospinal Radiotherapy: A Case Report

Abstract

Introduction: Pinealoblastomas are rare, aggressive, Grade 4 tumours of the pineal gland, predominantly affecting children. Their occurrence in adults is exceedingly rare, posing significant diagnostic and therapeutic challenges due to the lack of standardised management protocols. Case Presentation: The authors present the case of a 23-year-old woman with a 3-month history of hearing loss. Brain MRI revealed a large (6.5×5 cm), unresectable pineal region tumour causing obstructive hydrocephalus. Biopsy confirmed the diagnosis of pinealoblastoma. Initial attempts at radiotherapy were precluded by severe agitation. A multidisciplinary team decision led to treatment with induction chemotherapy (cisplatin and etoposide) followed by craniospinal radiotherapy (54 Gy total dose) using the volumetric modulated arc therapy technique. Outcomes: The patient tolerated the treatment well, with significant improvement in her neuropsychiatric status. A post-therapeutic MRI at 3 months showed an 80% tumour regression (near-complete remission) and resolution of hydrocephalus. The patient made a full neurological recovery and successfully resumed her university studies. Conclusion: This case demonstrates that a sequential approach of induction chemotherapy followed by high-dose radiotherapy can be a highly effective strategy for managing unresectable pinealoblastoma in adults, leading to excellent oncological and functional outcomes. It underscores the need for adaptive, multidisciplinary management and highlights the potential of non-surgical modalities.