br Materials and methods br Results br Discussion This
Materials and methods
Discussion This study is the first broad assessment of cancer incidence and mortality patterns and trends from the State Cancer Registry of Russia. The results revealed substantial and somewhat contrasting changes in trends of breast and cervical cancer in Russian women during the past decades. For cervical cancer, an alarming increase in incidence and mortality rates is clearly observed, while the pattern for breast cancer was not dissimilar to many European countries, with an increasing incidence trend and a downward mortality trend following an extended AR-13324 of increasing trends . Our results are consistent with previous reports on breast cancer mortality trends in Russia based on both available and reconstructed data, as well as the assessment of cervical cancer incidence trends and projections [14,33,34]. Our report is however the first to include combined analysis of both incidence and mortality trends for the most recent periods in Russia, and incorporate years of life lost and future predictions of the burden. The increasing risk of both breast and cervical cancer among birth cohorts of women born 1937–1953 can partly be explained by changing fertility patterns in Russia, with a strong decline in fertility at the beginning of the 20th century, reaching its lowest point in the 1950 s. The completed fertility rate declined until the 1945-50 birth cohort and was stable and low at around 2 for all subsequent cohorts . Decreasing birth rates may partially explain the initial increase in cohort-specific risk in breast cancer incidence and mortality, and the equivalent declines in cervical cancer incidence and mortality. Breast cancer incidence in the post-war generations was stable, probably attributable to several balancing factors, including declining fertility rates, increasing obesity prevalence and changing dietary habits, alongside improved diagnostics and opportunistic efforts at early detection. The rise of breast cancer incidence attributable to cancer screening observed in several European countries probably plays a lesser role in explaining the mortality decline in Russia , with the decrease in breast cancer mortality suggesting an improvement in diagnosis and treatment in Russia in recent years. Adjuvant therapy was introduced in the 1990 s in Russia and the first clinical trials were focused on early detection and the multimodality treatment of breast cancer; their indirect effect could have resulted in implementation of adjuvant protocols across oncology centers . It is also worthy to note the observed cohort-led decrease in mortality at younger ages (<55 years of age) is more likely to be effect of treatment. This finding is consistent with reports from other European countries . Increasing trends in cervical cancer cohort-specific incidence and mortality risk likely reflect changes in sexual behavior among young generations leading to increased persistence of high-risk HPV (hr-HPV) infection against a background of a continued absence of effective national screening programs. Detailed analysis of trends of HPV burden in Russia are not available. Based on cross-sectional data, the hr-HPV prevalence among women with normal cytology ranged from 0 to 48%, but was higher in women with intraepithelial lesions [39,40]. Although direct data on sexual behavior is not available, indirect measures such as the rise in the number of abortions in the USSR in the 1960 s could explain the observed cohort risk changes. While this may well reflect many other societal factors, in the absence of barrier and hormonal contraception methods, abortion was reported to be the most common measure of birth control in the USSR until the 1980s . Smoking prevalence was traditionally low in women in the USSR, but recent studies report a doubling of prevalence between 1992 and 2003 .