Does Reduced Renal Function Predispose to Cancer-specific Mortality from Renal Cell Carcinoma?

Area of Science:

• Nephrology
• Oncology
• Urology

Background:

• Recent studies suggest reduced kidney function is linked to increased kidney cancer mortality.
• These findings have led to recommendations for partial nephrectomy (PN) even for complex tumors.
• This study questions if confounding factors, not renal function itself, explain this association.

Purpose of the Study:

• To determine if preoperative estimated glomerular filtration rate (eGFR) or new baseline eGFR (NB-GFR) independently predict cancer-specific mortality (CSM) after nephrectomy.
• To investigate the association between renal function and CSM, cancer recurrence (CR), and all-cause mortality (ACM) in kidney cancer patients.

Main Methods:

• Retrospective review of 1605 patients with localized kidney cancer (T1-T3a/N0/M0) who underwent PN or radical nephrectomy (RN) between 1999-2008.
• Cox regression analyses were used to assess the impact of preoperative eGFR and NB-GFR on CSM, CR, and ACM.
• Key factors analyzed included age, tumor size, tumor grade, and histology.

Main Results:

• Neither preoperative eGFR nor NB-GFR showed a significant association with CSM or CR.
• Increased age, larger tumor size, high tumor grade (3/4), and clear-cell histology were significantly associated with increased CSM.
• Higher preoperative eGFR was linked to a reduced hazard of all-cause mortality (ACM).

Conclusions:

• The study's findings do not support the notion that greater preservation of renal function improves oncological outcomes in kidney cancer.
• Unfavorable oncological outcomes for localized renal cell carcinoma (RCC) are primarily associated with aggressive tumor characteristics.
• Renal function appears to be a less significant predictor of cancer outcomes compared to tumor biology.