Aim: To evaluate cancer risk in Brežice municipality in the period 1984-2003 and compare it with the period 1970-1983, before Krško nuclear power plant started operating in the vicinity.

Methods: A descriptive geographical epidemiological study was performed to compare the cancer relative risks (RR) on the national, regional, and local level. We estimated RR for all cancers combined, the five most common cancer sites, and thyroid cancer and leukemias. Standardized incidence ratio (SIR) was used as RR indicator. If the number of cancer cases was small, raw SIRs were smoothed by Bayesian hierarchical model.

Results: The number of new cancer cases, as well as the estimated RR for all and individual cancer sites, increased in the period 1984-2003 in Brežice municipality and all over Slovenia. In the period 1984-2003, SIR for all cancers combined in Brežice was below the national and regional average, but RR for colorectal and cervical cancer was above this average. There were no evident clusters of districts with higher/lower RR within Brežice municipality in the period 1984-2003. RR of thyroid cancer and leukemias in Brežice was comparable with Slovenian average both in this period and before it.

Conclusion: The obvious increase in cancer burden in Brežice municipality cannot be associated with Krško nuclear power plant, but most likely with unhealthy lifestyle.