Desmoplastic infantile gangliogliomas/astrocytomas: clinical course, surgery and morphological diagnosis

Desmoplastic infantile gangliogliomas (DIG) and astrocytomas (DIA) are benign brain tumors in infants. They comprise 1.3-15.8% of tumors in infants / young children and 0.5-1% in older children. In the latest 2021 WHO classification of the CNS tumors, DIG and DIA are included in the group of neuronal and glioneuronal tumors and considered as a single entity within this group despite some morphological differences. In this classification, they are classified as low-grade tumors (Grade I). However, several cases of DIG/DIA with aggressive behavior were described in the literature. OBJECTIVE: To analyze 2 different clinical courses of DIG/DIA with various neuroimaging signs, intraoperative situations and morphological pictures with review of appropriate literature. MATERIAL AND METHODS: Two main courses of disease in children with DIG/DIA are presented. The first one is characterized by rapid growth of tumor, its large size upon diagnosis with progressive intracranial hypertension. The second type includes slow growth, small size, and only focal neurological symptoms. RESULTS AND CONCLUSION: DIG/DIA are rare tumors and most often diagnosed in the first 2 years of life. They have some common neuroradiological and histological features with malignant brain tumors (malignant glioma of infancy, PNET), but another prognosis. Aggressive clinical course, rapid tumor growth, MR-based differential diagnosis involving multiple histological forms and histopathological findings potentially mimicking malignant tumor complicate differential diagnosis, as it was in the second case. Probably, such an aggressive clinical course is associated with significant spread of neoplastic astrocytic and neuronal components with foci of primitive embryonic cell complexes with increased proliferative index. Surgery is preferable. Difficult resection of these tumors is associated with rich vascularity, high risk of fatal bleeding, no border with normal brain tissue, and tendency to infiltrate functionally significant structures of the central nervous system.