Objective: The prevalence as well as immunohistochemical (IHC) study of latent, incidentally found prostate cancer (LPC) as well as precancer lesions, in patients, who underwent surgery for BPH were studied. Method: BPH samples were obtained by prostatectomy from 120 Ukrainian patients consisting of 30 patients from areas without radio-contamination (control group 1) and of 90 patients living in 137Cs contaminated areas of Ukraine (group 2). Ki-67, p53, p27Kip-1, p63 and Bcl-2 proteins were IHC investigated in BPH from all patients. Results: The incidences of LPC (Gleason score 4), chronic prostatitis, PIA and PIN were 16.67, 53.34, 20, and 26.67 % in group 1; 12.23, 64.45, 43.45 and 36 .67 % in group 2, respectively. Greatly elevated levels of p53, Ki-67, Bcl-2 associated with decreased levels of p27Kip-1and p63 in areas of PIA and less LPC and PIN in group 2 to compare with group 1 patients were obtained with statistically significant differences. Conclusion: Our study suggests that chronic long-term lowdose radiation exposure might result in the increase of chronic inflammation and it is now found to be associated with increased incidences of PIA and PIN in BPH accompanied by p53, p27KIP-1 and Bcl-2 alteration which in turn could lead to prostate carcinogenesis.