Supratentorial tumors typical of the infantile age: desmoplastic infantile ganglioglioma (DIG) and astrocytoma (DIA). A review

Desmoplastic infantile gangliogliomas (DIGs) and desmoplastic infantile astrocytomas (DIAs) are tumors typical of the infantile age. A large size, with a mixed solid and cystic component, clinical presentation with progressing signs of increased intracranial pressure, a prominent benign desmoplastic structure at histological examination, and a favorable clinical course in the majority of cases are the prominent features of these tumors. The objective of the present paper was to review the pertinent literature on the topic together with our personal experience, with the aim of an updated review of the subject.

Only 28 papers are present in the literature devoted to DIGs and DIAs, most of them reporting on single cases or small series, with a total of 107 patients aged from 5 days to 48 months with a slight male prevalence. Most of the reported cases refer to supratentorial and hemispheric locations, a few cases involving the hypothalamic region, the posterior fossa, and the spinal cord. The typical MRI appearance is of large mixed solid and cystic tumors with a spontaneous hyperintense T2 appearance of the solid part which also shows a strong contrast enhancement. Mixed ganglionic and astrocytic cells are identifiable in DIGs, whereas DIAs are typically featured by the exclusive presence of glial cells. In both cases, more primitive cells may be observed, which present a higher number of mitoses and these areas can mimic the features of malignant astrocytomas. Surgery represents the treatment of choice; however, radical removal has been reported as possible only in around 30 % of the cases: the low age of the patients together with their low weight and the large size of and the hyper-vascularized structure of the tumors represent the main factors limiting surgery. Pure observation is considered as first choice in children undergoing a partial/subtotal tumor resection, chemotherapic regimens being considered in cases of recurrences after a second look surgery. Long-term prognosis is favorable with mortality being related mostly to the rare midline (i.e., hypothalamic) locations, which beyond the functionally relevant site, tend to have an unusually more aggressive histological behavior.