Abstract
Background/Objectives: The aim of this study is to assess the prognostic implications of metastatic anatomical location in patients with recurrent bladder cancer (BC) after cystectomy. Methods: The study is a retrospective cohort study. All data were collected from a clinical database from Aarhus University Hospital. Kaplan-Meier curves were used to analyse survival probabilities. Crude and adjusted Cox regression was used to calculate the hazard ratios (HRs) for overall mortality between different locations of metastases and the number of metastases. Results: In total, 180/664 (27.1%) patients who underwent radical cystectomy as a treatment of BC in the time period from 2015 to 2021 ultimately developed recurrent disease. The median follow-up period was 433 days (Q1: 256, Q3; 847). In a crude analysis for overall mortality, patients with both lymph node and distant organ metastasis had a worse prognosis than patients with lymph node metastasis only (HR = 2.25 (95% CI: 1.36-3.75, p = 0.002)). In the adjusted analysis, patients with ≥2 metastatic sites had higher hazard than patients with only a single site of recurrence (HR = 1.63 (95% CI: 1.15-2.33, p = 0.01)). Patients with organ metastasis had higher hazard ratios than patients with lymph node metastases and local recurrence only (HR = 1.74 (95% CI: 1.07-2.84, p = 0.026)). When analysing patients with single metastasis, there was a statistically significant difference in overall survival probability in the following groups: lymph node metastasis, other organ metastases, bone metastasis (p = 0.04). Conclusions: This study shows potentially clinically relevant associations between the anatomical location of metastases and patients' prognosis. Furthermore, we were able to demonstrate an association between a higher number of metastatic sites and a worse prognosis.