抄録
Although several rare congenital syndromes are associated with hypersensitivity to radiotherapy, the extent to which genetic factors modulate the radiosensitivity of cells from “normal” individuals is largely unknown. Some evidence exists that fibroblasts from apparently normal patients who sustained unusually severe radiation reactions are more radiosensitive in vitro than cells from patients treated similarly whose reactions were not excessive. Other data show that tumor cells from cancers that recur after radiotherapy are on average less radiosensitive in vitro than cells from tumors that are cured. Finally, there are fragmentary clinical data suggesting that a correlation may exist between the severity of normal tissue reactions to radiotherapy in a given patient and the probability of tumor control. All of these data are consistent with the hypothesis that genetic factors modulate the radiosensitivity of both normal and neoplastic cells from patient to patient. If this hypothesis is true, development of assays precise enough to identify patients who are significantly more or less radiosensitive than average would allow radiation doses to be titrated according to individual radiosensitivity with an improvement of the therapeutic ratio for all patients.
