A scanning electron microscopic examination of retinoblastoma in tissue culture.

Tissue cultures were established from 6 retinoblastomas and the cultured cells examined by scanning electron microscopy. Cells from cultures of normal fetal retinal and glial tissue were also examined by SEM. Though a number of different cell types were found to coexist in the retinoblastoma cultures, most had the features of cells of either glial or neuronal origin. Evidence of further differentiation of cells in each series was seen. These findings indicate that the cell of origin in retinoblastoma is a multipotential stem cell which, though neoplastic, is still capable of differentiation into both glial and neuronal series.