Malignant desmoplastic infantile astrocytoma? A case report and review of the literature

Desmoplastic infantile astrocytoma (DIA) and ganglioglioma (DIG) are uncommon and generally benign intracranial tumors that typically affect infants. Unusual cases bearing aggressive clinical and malignant histological features have been described in the literature. We report a patient who was diagnosed at the age of 6 weeks with a DIA that relapsed 3 months postoperatively despite gross total resection (GTR). Pathologic examination revealed several mitoses, not only in the primitive neuroectodermal tumor (PNET)-like areas, but also unexpectedly in the predominating spindle cell component. The Ki67 proliferative index within the spindled component was 25%. The tumor continued to grow after initial relapse despite two courses of intensive chemotherapy (including vincristine, carboplatin, and temozolomide), but the recurrence was eventually controlled with oral etoposide. Currently, the patient is stable at 9 months after her initial diagnosis. This case illustrates that rare cases of DIA may display malignant histologic features in the typically benign and predominating spindle cell component and behave in an aggressive clinical manner despite GTR. As such, we recommend early and extended clinical follow-up of all DIA and DIG cases.