PURPOSE: The purpose of this study was to determine whether the distribution of radiosensitivities in normal tissues of head and neck cancer patients, measured using a DNA damage assay on lymphocytes, is likely to provide sufficient discrimination to enable reliable identification of patients with abnormal sensitivities. MATERIAL AND METHODS: Radiosensitivity was assessed in 307 lymphocyte samples from unselected head and neck cancer patients and was quantified as the initial number of DNA double-strand breaks (dsb) induced per Gray and per DNA unit (200 Mbp). RESULTS: The existence of an inter-individual variation in the radiosensitivity parameter is described by the range (0.41--9.38 dsb/Gy/DNA unit) of the values found. We detected 37 patients who developed severe skin reactions during radiotherapy treatment and we compared their radiosensitivity values with the remaining patients treated. Radiosensitivity values of >7.20 dsb/Gy/DNA unit should theoretically correspond to highly radiosensitive patients. CONCLUSIONS: Our results suggest that initial DNA damage measured on lymphocytes offers an approach to predict the acute response of human normal tissues prior to radiotherapy. . Copyright (c) 2005 S. Karger AG, Basel.
PURPOSE: The purpose of this study was to determine whether the distribution of radiosensitivities in normal tissues of head and neck cancerpatients, measured using a DNA damage assay on lymphocytes, is likely to provide sufficient discrimination to enable reliable identification of patients with abnormal sensitivities. MATERIAL AND METHODS: Radiosensitivity was assessed in 307 lymphocyte samples from unselected head and neck cancerpatients and was quantified as the initial number of DNA double-strand breaks (dsb) induced per Gray and per DNA unit (200 Mbp). RESULTS: The existence of an inter-individual variation in the radiosensitivity parameter is described by the range (0.41--9.38 dsb/Gy/DNA unit) of the values found. We detected 37 patients who developed severe skin reactions during radiotherapy treatment and we compared their radiosensitivity values with the remaining patients treated. Radiosensitivity values of >7.20 dsb/Gy/DNA unit should theoretically correspond to highly radiosensitive patients. CONCLUSIONS: Our results suggest that initial DNA damage measured on lymphocytes offers an approach to predict the acute response of human normal tissues prior to radiotherapy. . Copyright (c) 2005 S. Karger AG, Basel.
Authors: Munira A Kadhim; Ryonfa Lee; Stephen R Moore; Denise A Macdonald; Kim L Chapman; Gaurang Patel; Kevin M Prise Journal: Mutat Res Date: 2010-03-27 Impact factor: 2.433