Breast cancer incidence risk in accidentally exposed persons of the Southern Urals

Abstract

The objective of the paper is to assess the breast cancer incidence risk in the Ural cohort of accidentally exposed population. The cohort of people exposed in the Southern Urals on the Techa River and in the East Ural Radioactive Trace was created in 2018. This is the first time that breast cancer risk analysis in women in this cohort is being carried out. Over the period from 1956 to 2018, 337breast cancer cases and 741,533person-years at risk were reported in the female subcohort in the incidence catchment area. Mean accumulated dose to the mammary gland, calculated using the TRDS-2016 dosimetry system, was 46 mGy, the maximum dose was 1 Gy. Regression analysis was performed using the EPICURE software package. Statistical significance with 95% probability was assessed by the maximum likelihood method. As a result of the analysis, a statistically significant linear dependence of breast cancer parameters on the dose was obtained. Excess relative risk for the follow-up period from 1956 through 2018 for members of the female subcohort with a 5-year latency period was 2.39 / Gy. The paper also discusses the impact of available for analyses non-radiation factors on both baseline rates of breast cancer incidence and those associated with radiation exposure. These results do not contradict those obtained in the previous study in the Techa River Cohort separately, and in the Japanese L SS cohort of atomic bomb survivors.

Keywords

• breast cancer
• ural cohort of accidentally exposed population
• radiogenic risk
• excess relative risk