Photo Credit: Nemes Laszlo

The following is a summary of “Evaluation of American Urological Association Renal Cell Carcinoma Risk Groups for Chromophobe Renal Cell Carcinoma,” published in the August 2024 issue of Urology by Britton et al.

This study aimed to develop and compare various models for risk stratification in chromophobe renal cell carcinoma (chrRCC), focusing on their ability to predict progression-free survival (PFS) and cancer-specific survival (CSS) after surgery. Current risk models for renal cell carcinoma (RCC) typically exclude chrRCC, as nuclear grading is not recommended for this subtype. To address this gap, researchers utilized the institutional registry to identify patients who underwent surgery for unilateral, sporadic, M0 chrRCC between 1970 and 2012. The study group then applied the American Urological Association (AUA) risk group criteria—excluding nuclear grade—and compared them to the Mayo Clinic risk system, which includes nodal involvement, perinephric/renal sinus fat invasion, and sarcomatoid differentiation. PFS and CSS were estimated using the Kaplan-Meier method, and the predictive accuracy of each model was assessed using c-indexes derived from Cox proportional hazard regression models.

In total, 257 patients were analyzed, of whom 39 experienced disease progression at a median follow-up of 30 months, and 25 died from chrRCC at a median follow-up of 34 months post-surgery. The 10-year PFS and CSS rates were 84% and 90%, respectively. The c-indexes for predicting PFS using the modified AUA and Mayo risk groups were 0.76 and 0.75, respectively, while for CSS, the c-indexes were 0.77 and 0.76, indicating comparable predictive performance between the two models.

In conclusion, the modified AUA and Mayo risk stratification systems demonstrate similarly vital predictive accuracy for PFS and CSS in patients with chrRCC. These models can effectively guide patient counseling based on pathological features, inform clinical follow-up strategies, and help identify candidates for adjuvant systemic therapy trials aimed at improving long-term outcomes.

Source: sciencedirect.com/science/article/abs/pii/S0090429524006447