CUA 2018: The Association Between Baseline Renal Function And Oncologic Outcomes After Radical Cystectomy

Halifax, Nova Scotia ( In recent literature, there has been speculation about the role of renal function in regard to cancer disease progression. According to some, decreased renal function has been identified as a potential risk factor in cancer recurrence and mortality due to malignancy. Though this was previously reviewed, there has not been a published account of whether decreased renal function is responsible for worsening outcomes among patients with urothelial carcinoma (UC). To expand on this issue, Ross Mason, MD, from the Mayo Clinic in Rochester, Minnesota attempted to examine the association between preoperative renal function and oncological outcomes after radical cystectomy (RC). 

To test his research question, Dr. Mason and his team conducted a retrospective chart review of all patients treated with RC for UC at their center from 1980 to 2017. Patients were screened if they were without neoadjuvant chemotherapy and who had a preoperative serum creatinine measurement available. Using the CKD-EPI formula, estimated glomerular filtration rate (eGFR) was calculated preoperatively and analyzed as a binary variable ≥ or < 60 mL/min/1.73m2. Cox proportional hazard regression models were calculated and risk analysis were utilized to evaluate the association between preoperative eGRF and recurrence-free survival, cancer-specific survival, and overall survival. 

Following completion of the study, an impressive 1,232 patients were identified for inclusion in the study: 683 patients had an eGFR ≥ 60 mL/min/1.73m2 while 549 had an eGFR < 60 mL/min/1.73m2. Median age was significantly higher in the eGFR group that was < 60 mL/min/1.73m2. Median follow up was 10.7 years; 487 patients were diagnosed with recurrence, 455 died of UC, and 1,004 patients died overall. Having an eGFR < 60 mL/min/1.73m2 seemed to not be significantly associated with cancer-specific survival and recurrence-free survival. However, this cohort was associated with a significantly lower overall survival as compared to the eGFR ≥ 60 mL/min/1.73m2. The Kaplan-Meier curve illustrating this is included in the image below. 
As he neared the end of his presentation, Dr. Mason reiterated his main conclusion stating that low eGFR is associated with only worse overall survival but not recurrence-free survival or cancer-specific survival. Also, he explained that the presence of baseline chronic kidney disease may be used to assess non-cancer death risk in future prognostic models for outcomes following radical cystectomy for urothelial carcinoma. 

Presented by: Ross Mason, MD, Urology, Mayo Clinic, Rochester, MN, United States
Co-Authors: Bimal Bhindi1, Igor Frank1, Prabin Thapa2, Matthew K Tollefson1, Houston Thompson1, Jeffrey Karnes1, Stephen A Boorjian1
1Urology, Mayo Clinic, Rochester, MN, United States; 2Health Sciences Research, Mayo Clinic, Rochester, MN, United States

Written by: Zachary Valley, Twitter: @ZacharyAValley, Department of Urology, University of California-Irvine at the 73rd Canadian Urological Association Annual Meeting - June 23 - 26, 2018 - Halifax, Nova Scotia