Characterization and radiobiologic parameters of medulloblastoma in vitro.

Cultured cells from human medulloblastomas were demonstrated to have distinctive features and a "glial" potential from the morphological and ultrastructural parameters. The in vitro radiobiological survival curve parameters of cultured human medulloblastoma and non-malignant skin fibroblasts obtained under the same conditions of exponential growth were similar. In vitro conditions may underestimate the shoulder region of the survival curve. Since the shoulder region is the most important in clinical fractionated radiotherapy, multiple dose experiments might be useful in examining this portion of the survival curve more closely.