Background: To determine the utility of creatinine-to-hemoglobin (Cr:Hgb) ratio, as a predictor of survival outcomes in upper tract urothelial carcinoma (UTUC).
Methods: We performed a multi-institutional retrospective analysis of UTUC-patients who underwent robotic radical nephrouretectomy utilizing the ROBUUST (ROBotic surgery for Upper Tract Urothelial Cancer Study) registry. Patients were divided into elevated Cr:Hgb ratio (>0.15, based on upper-limit of normal for creatinine and lower-limit of normal for hemoglobin) vs. non-elevated Cr:Hgb ratio (≤0.15). Primary outcome was all cause mortality (ACM)/overall survival (OS). Secondary outcomes were cancer-specific mortality (CSM) / survival (CSS) and recurrence-free survival (RFS). Cox proportional hazards (MVA) was used to elucidate predictive factors for ACM, CSM, and RFS. Kaplan-Meier analysis (KMA) was performed to analyze 5-year OS, CSS, and RFS.
Results: Overall, 829 patients were analyzed (744 non-elevated / 85 elevated Cr:Hgb). Elevated Cr:Hgb patients had more frequently advanced-stage (P=0.016) and high-grade tumors (P<0.001) at time of surgery. MVA demonstrated increasing-age (HR=1.04, P=0.002), elevated Cr:Hgb (HR=2.49, P=0.003), lympho-vascular invasion (HR=4.61, P<0.001), and higher-stage (HR=3.82, P<0.001) to be associated with worsened ACM. Increasing-age (HR=1.04, P=0.030), elevated Cr:Hgb (HR=3.64, P<0.001), and lympho-vascular invasion (HR=4.52, P<0.001) were independently associated with worsened CSM. Elevated Cr:Hgb (HR=1.27, P=0.001) was independently associated with worsened recurrence. For elevated vs. non-elevated Cr:Hgb patients, KMA revealed significantly worse 5-year OS (78% vs. 65%, P=0.002), CSS (86% vs. 74%, P<0.001), and RFS (53% vs. 22%, P=0.004).
Conclusions: Baseline elevated Cr:Hgb predicted worsened survival outcomes in UTUC patients and may serve a pre-operative marker to stratify oncologic risk and guide counseling and management.