Garazi Ruiz de Azua Unzurrunzaga1, David H Brewster2, Sarah H Wild1, Vanitha N Sivalingam3. 1. Usher Institute for Population Health Sciences and Informatics, University of Edinburgh, Edinburgh, United Kingdom. 2. Scottish Cancer Registry, NHS National Services Scotland, Gyle Square, 1 South Gyle Crescent, Edinburgh EH12 9EB, United Kingdom. 3. Division of Cancer Sciences, Faculty of Biology, Medicine and Health, University of Manchester, United Kingdom. Electronic address: vanitha.sivalingam@manchester.ac.uk.
Abstract
AIM: The prevalence of hysterectomy is decreasing worldwide. It is not clear whether changes in the population at risk (women with intact uteruses) have contributed to an increased uterine cancer incidence. This study aims to assess the effect of changing trends in hysterectomy prevalence on uterine cancer incidence in Scotland. METHODS: The population of women aged ≥25 years with intact uteri was estimated using the estimated hysterectomy prevalence in 1995 and the number of procedures performed in Scotland (1996-2015). Age-standardized uterine cancer incidence was estimated using uncorrected (total) or corrected (adjusted for hysterectomy prevalence) populations as denominators and the number of incident cancers as numerators. Annual percentage change in uterine cancer was estimated. RESULTS: Hysterectomy prevalence fell from 13% to 10% between 1996-2000 and 2011-2015, with the most marked decline (from 20% to 6%) in the 50-54-year age group. After correction for hysterectomy prevalence, age-standardized incidence of uterine cancer increased by 20-22%. Annual percentage change in incidence of uterine cancer remained stable through the study period and was 2.2% (95%CI 1.8-2.7) and 2.1% (95%CI 1.7-2.6) for uncorrected and corrected estimates, respectively. CONCLUSION: Uterine cancer incidence in Scotland corrected for hysterectomy prevalence is higher than estimates using a total female population as denominator. The annual percentage increase in uterine cancer incidence was stable in both uncorrected and corrected populations despite a declining hysterectomy prevalence. The rise in uterine cancer incidence may thus be driven by other factors, including an ageing population, changing reproductive choices, and obesity.
AIM: The prevalence of hysterectomy is decreasing worldwide. It is not clear whether changes in the population at risk (women with intact uteruses) have contributed to an increased uterine cancer incidence. This study aims to assess the effect of changing trends in hysterectomy prevalence on uterine cancer incidence in Scotland. METHODS: The population of women aged ≥25 years with intact uteri was estimated using the estimated hysterectomy prevalence in 1995 and the number of procedures performed in Scotland (1996-2015). Age-standardized uterine cancer incidence was estimated using uncorrected (total) or corrected (adjusted for hysterectomy prevalence) populations as denominators and the number of incident cancers as numerators. Annual percentage change in uterine cancer was estimated. RESULTS: Hysterectomy prevalence fell from 13% to 10% between 1996-2000 and 2011-2015, with the most marked decline (from 20% to 6%) in the 50-54-year age group. After correction for hysterectomy prevalence, age-standardized incidence of uterine cancer increased by 20-22%. Annual percentage change in incidence of uterine cancer remained stable through the study period and was 2.2% (95%CI 1.8-2.7) and 2.1% (95%CI 1.7-2.6) for uncorrected and corrected estimates, respectively. CONCLUSION: Uterine cancer incidence in Scotland corrected for hysterectomy prevalence is higher than estimates using a total female population as denominator. The annual percentage increase in uterine cancer incidence was stable in both uncorrected and corrected populations despite a declining hysterectomy prevalence. The rise in uterine cancer incidence may thus be driven by other factors, including an ageing population, changing reproductive choices, and obesity.