Long-term exposure to low doses of ionizing radiation and COVID-19 pandemic: oncohematological aspects.

For more than 35 years after Chornobyl catastrophe, about 5 million people in Ukraine, Republic of Belarus and Russian Federation inhabit the territories that are residually contaminated with long-lived radionuclides such as 137Cs, 90Sr. The previous studies of the Reference Laboratory operating at RE Kavetsky Institute of Experimental Pathology, Oncology and Radiobiology allowed specifying the effects of the protracted low dose irradiation on the state of the hematopoietic and lymphoid tissues resulting in the increased proportion of the B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma and acute myeloid leukemia among the patients referred from the contaminated areas of Ukraine. Since the beginning of 2020, these effects of radiation were superimposed by the factors associated with COVID-19 pandemic. SARS-CoV-2 infection is associated with the significant impact on hematopoiesis and immune system. Particular attention should be given to the role of such combined burden in the development of the immunodeficiency-associated lymphoid neoplasms. The extensive studies of the combined effects of low dose irradiation and COVID-19 within the large affected populations could be made a priority in future endeavors of epidemiologists and oncohematologists.

Recent trends in cancer incidence in Kiev 1969-1979.

The analysis of the trends of age-adjusted incidence rates of malignant tumors in the city of Kiev in the years 1969-1979 revealed a gradual increase of the majority of individual sites, mainly of the malignant tumors of rectum, lymphoid and hematopoietic tissues in both sexes and of breast in females. On the other hand a decrease of incidence rates of the malignancies of skin, lip and stomach in both sexes and of oesophagus, lung and uterine cervix in females was noted. These investigations formed the basis of the prognosis study of incidence rates of malignant tumors in Kiev until 1990. The importance of the study of incidence rates and trends of individual sites of malignant tumors for the investigation of their factors and causes in urban conditions and environment is emphasized.