Prevalence and oncologic impact of chronic kidney disease for upper tract urothelial carcinoma in endemic area.

Objective: This study aimed to assess the impact of preoperative chronic kidney disease (CKD) on the oncological outcomes of patients with upper tract urothelial carcinoma (UTUC) who underwent standard radical nephroureterectomy (RNU).

Methods: A total of 1172 UTUC patients who received RNU at a single center in Taiwan between February 2005 and August 2019 were included. The patients were categorized into two groups based on their preoperative CKD stage: CKD stage ≤3 (811 patients) and CKD stage >3 (361 patients). The estimated glomerular filtration rate (eGFR) was calculated using the Modification of Diet in Renal Disease (MDRD) formula. The study investigated the oncological outcomes, including intravesical recurrence, non-urothelial recurrence, and cancer-specific mortality, stratified by preoperative CKD status.

Results: The main findings indicated that UTUC patients with CKD stage >3 in Taiwan exhibited a higher proportion of females (p < 0.001), a greater history of concurrent bladder cancer (p = 0.003), more multifocal tumor behavior (p < 0.001), a higher incidence of carcinoma in situ (p = 0.008), increased rates of intravesical recurrence (p < 0.001), a lower prevalence of smoking history (p = 0.003), lower utilization of adjuvant chemotherapy (p < 0.001), reduced occurrence of non-urothelial recurrence (p < 0.001), and lower cancer-specific mortality (p = 0.006) compared to patients with CKD stage ≤3. Multivariate Cox regression analysis revealed significant differences in intravesical recurrence (p = 0.014) and non-urothelial recurrence (p = 0.006) between the CKD stage >3 and CKD stage ≤3 groups. The study also demonstrated that patients with concurrent bladder cancer and variant histology had higher rates of intravesical recurrence, non-urothelial recurrence, and cancer-specific mortality. The CKD stage >3 group exhibited lower rates of intravesical recurrence (p = 0.0014), higher rates of non-urothelial recurrence (p < 0.0001), and increased cancer-specific mortality (p = 0.0091) compared to the CKD stage ≤3 group in the 5-year free survival analysis.

Conclusion: In Taiwan, UTUC patients with CKD stage >3 exhibit distinct characteristics compared to the general population with urothelial carcinoma. They are associated with a non-smoking status, a higher proportion of females, and less aggressive pathological features. Additionally, CKD stage >3 can serve as a clinical indicator for intravesical and non-urothelial recurrence. Further investigation into molecular aspects and treatment modifications for these patients is warranted.