Good clinical course in infants with desmoplastic cerebral neuroepithelial tumor treated by surgery alone.

Abstract

We investigated why surgery alone provides for a benign clinical course in patients with desmoplastic infantile ganglioglioma and astrocytoma (DIG/A). The clinical course of 4, less than six-month-old girls, surgically treated at our institutions, was evaluated retrospectively. All presented with the clinical symptom of increasing head circumference. CT and MRI scans revealed a solid tumor attached to the dura that was surrounded by large, multiple cysts, in fronto-temporo-parietal lobe. Gross total removal succeeded in all 4 cases because the solid components of the tumor were very firm in contrast to the soft adjacent brain tissue. Microscopically, the surgical specimens consisted almost entirely of dense fibrous connective tissue containing generally elongate cells with inconspicuous cytoplasm. Most of these cells were immunopositive for GFAP. There was no evidence of tumor cells in the cyst wall. In 3 cases, some small neurons were positive for neurofilament immunostain. A high proportion of undifferentiated small cells in a less demoplastic area far from the dura were immunopositive for MIB-1. All of the 4 patients have been free of recurrence for more than five years. In patients with DIG/A, there are 5 reasons for a good clinical course. [1] At surgery, the tumor margin is clearly discernible because of the difference between the solid tumor and the soft adjacent brain tissue. [2] The tumor is located in the superficial cerebral hemisphere. [3] Large, multiple cysts surround the tumor. [4] The growth point appears to be adjacent to the cysts. [5] The cyst walls are free of invading tumor cells.