A Propensity Score–Matched Analysis of the Impact of Carcinoma In Situ on the Clinical Outcomes in Patients with Upper Tract Urothelial Carcinomas—A Nationwide Multi-Institutional Cohort Study

This study aimed to explore the clinical prognostic features of patients treated with radical nephroureterectomy for upper tract urothelial carcinoma (UTUC) with carcinoma in situ (CIS) compared with those without it. We retrospectively reviewed the data of 3285 patients with UTUC. Propensity scores were calculated using a logistic regression model to regress disease status on various baseline covariates, including cell type, tumor size, histology, lymphovascular invasion, surgical margin, and pathological stage. Using these scores, we adopted a one-to-two pair matching approach to form matched pairs between the two groups, ensuring patients within each pair had similar propensity score values. Prognostic factors were identified using univariate and multivariate Cox regression models. The Kaplan-Meier method was used to estimate the rates of prognostic outcomes, and survival curves were compared using the stratified log-rank test. Matched cohorts of 810 patients without and 405 with CIS from each group were compared. There was no discernible difference in the 5-year overall survival. The Kaplan-Meier curves for cancer-specific survival were significantly different in the adjusted group only (P = .043). Multivariate Cox regression analyses indicated that disease-free and bladder recurrence-free survival rates were similar between the two groups. The CIS status was not significantly correlated with the disease-free or bladder recurrence-free survival (P = .066 and .179, respectively). Patients with UTUC with CIS did not exhibit significantly worse oncologic outcomes than those without it.