The potential role of G2- but not of G0-radiosensitivity for predisposition of prostate cancer.

Abstract

Comparing the chromosomal radiosensitivity of prostate cancer patients with that of healthy donors. The study was performed on 81 prostate cancer patients characterised by a clinical stage of predominantly pT2c or pT3a and a median age of 67 years. As healthy donors 60 male monozygotic twin pairs were recruited with a median age of 28 years. Chromosomal radiosensitivity was measured using both G0- and G2-assay. No difference between healthy donors and prostate cancer patients was detected concerning G0-radiosensitivity, since medians were similar (Hodges-Lehmann estimate: -0.05, 95% CI: -0.18-0.08, p=0.4167). However, a pronounced difference was determined for G2-radiosensitivity with prostate cancer patients showing a significantly higher sensitivity compared to healthy donors (Hodges-Lehmann estimate: -0.41, 95% CI: -0.53 to -0.30, p=1.75(-9)). Using the 90% quantile of G2-radiosensitivity in healthy donors as a threshold for discrimination the fraction of prostate cancer patients with elevated radiosensitivity increased to 49%. G2-, but not G0-radiosensitivity is a promising marker for predisposition of prostate cancer.