Incidence and mortality of upper tract urothelial carcinoma in Korea: A nationwide population-based study conducted from 2002 to 2020.

Purpose: To describe the incidence and mortality of upper tract urothelial carcinoma (UTUC) from 2002-2020 using data from the Korean National Health Insurance Service, which contains data from the entire Korean population.

Materials and methods: Reimbursement records for 43,255 patients diagnosed with primary UTUC (according to the International Classification of Disease 10th revision code C65 and C66) between 2002-2020 were retrieved. The study period was split into four: period I (2002-2005), period II (2006-2010), period III (2011-2015), and period IV (2016-2020). Trends were quantified by calculating the annual percentage change (APC). Mortality data were obtained from the Statistics Korea.

Results: From 2002-2020, the incidence of UTUC in Korea increased gradually from 9.34 to 11.40 per 100,000 person-years. Although there was a male predominance, the male to female ratio did not change significantly over time; however, age at the time of diagnosis, the comorbidity index, and the proportion of patients undergoing open/laparoscopic surgery increased significantly over time. There was a modest improvement in 5-year survival (both all cause- and cancer-specific) over the study period. Multivariate analysis identified age at diagnosis, sex, the comorbidity index, and open/laparoscopic surgery as being associated with survival.

Conclusions: Between 2002 and 2020, the incidence of UTUC in Korea showed a general upward trend; however, survival outcomes have improved. These representative datasets from the Korean population might provide crucial information that enables clinicians to better understand of the epidemiology of UTUC in Korea.