Frequency distribution of the individual
γH2AX foci per cell as measured in ex vivo irradiated lymphocytes after immunostaining. 59 healthy individuals (blue bars) were compared to 136 rectal cancer patients (red bars). The data were fitted using a Gaussian distribution for the (A) preexisting γH2AX foci, (B) initial γH2AX foci 30 min post IR with 0.5 Gy (C) remaining γH2AX foci 24 h post IR with 2 Gy. Dashed blue vertical lines indicate the value of two and three standard deviations from the mean of the healthy individuals and solid red lines the value of two and three standard deviations from the mean of the RC patients, respectively. (D) Preexisting γH2AX foci were correlated to remaining γH2AX foci 24 h post IR with 2Gy. HI = healthy individuals, RC = rectal cancer patients.