Correlation of mRENAL score with clinical outcomes after CT-guided renal cell carcinoma cryoablation: A retrospective observational study

Background and objective: CT-guided cryoablation (CRA) has emerged as a safe and effective minimally invasive treatment for renal cell carcinoma (RCC), though outcomes can vary. The mRENAL score may help to predict clinical outcomes. The main objective of this study was to evaluate the correlation between mRENAL score and clinical outcomes in RCC cases treated by CT-CRA.

Methodology: This was an observational, retrospective, single-center study that included CT-CRA procedures performed on RCCs between 2017 and 2023. Tumors were classified into three categories based on the mRENAL score: low, intermediate, and high risk. We employed the Firth logistic regression for multivariate analysis due to the small sample size and rare outcome events.

Results: Our data included 53 cases, with a mean age of 53 ± 12 years. Technical success was achieved in all cases. Four cases had disease recurrence at the site of previously treated RCC (4/42, 9.5%), as 11 cases lost follow-up imaging. The Firth logistic regression analysis revealed that increasing mRENAL score was associated with a higher risk of recurrence (adjusted odds ratio = 0.42 [95% CI, 0.19–0.95]; P = 0.038). This trend towards statistical significance implies that for every 1-point increase in mRENAL score, the odds of clinical success decrease by at least 5% with over 95% confidence. No procedure-related mortality was observed.

Conclusion: Our analysis demonstrates that the mRENAL score may help predict clinical outcomes, with lower mRENAL scores associated with higher clinical success rates following CT-CRA of RCC.