Abstract
INTRODUCTION AND IMPORTANCE: Glioblastoma multiforme (GBM), a grade 4 astrocytoma, represents a predominant malignant primary tumor within the central nervous system (CNS) and is known for its dismal prognosis. While extremely uncommon in pediatric cases, the small cell glioblastoma (scGBM) variant poses diagnostic challenges due to overlapping histopathological features with other intracranial tumors. CASE PRESENTATION: We present the case of a 9-year-old Persian boy who underwent a craniotomy due to a malignant brain tumor. The histopathological examination, followed by ancillary immunohistochemical and molecular studies, led to the rare diagnosis of scGBM. Following a course of 32-session adjuvant radiotherapy, the tumor recurred with a peculiar manifestation, a subcutaneous mass at the previous surgical site, as a result of recurrent tumor invasion through craniotomy defect. CLINICAL DISCUSSION: Small-cell glioblastoma (scGBM) presents aggressive features, often misdiagnosed as other tumors. A rare pediatric occurrence, scGBM requires careful histopathological and molecular evaluations. Treatment aligns with classic GBM protocols, but prognosis is poor, with overall survival ranging from 5 to 23 months. CONCLUSION: The case highlights the diagnostic intricacies in distinguishing scGBM from other morphologically similar intracranial tumors, especially in pediatric patients. The report contributes to the limited literature on scGBM in the young population, emphasizing the significance of refined diagnostic approaches for accurate diagnosis and appropriate succeeding treatment for the best patient result.