LATE ONCOLOGICAL AFTEREFFECTS OF RADIATION EXPOSURE CAUSED BY THE CHORNOBYL ACCIDENT.

Studies of the longterm oncological consequences after the Chornobyl accident show a significant impact of radiation exposure on the cancer incidence rate in affected population in Ukraine. This is supported by the increased radiation risk of leukaemia in liquidators, which exceeds national population rates, and its value is comparable to the data on hibakushi, who were subjected to Abombings. For the first time in the cleanup workers cohort the radiation dependence of chronic lymphoid leukaemia was established. There are radiation associated risks of leukemia in children who have been exposed to radiation from the Chornobyl accident. There has been registered an increase of thyroid cancer incidence in children and adults (liquidators, evacuees from the 30km exclusion zone and residents of the most contaminated territories). There is an excess of breast cancer in female liquidators. The frequency of all forms of malignant neoplasms decreases over time but still exceeds national rates. Further monitoring of malignant neoplasms in the groups of affected population will allow evaluating the radiation risks of cancer forms whose radiationassociated manifestation is already known from previous studies or can be expected in the future.