Purpose: To evaluate whether the choice of thermal ablative modality impacts the rate of perioperative complications and treatment outcomes for anatomically complex renal cell carcinoma (RCC).
Materials and Methods: A retrospective analysis was performed for 83 patients (M:F = 51:32, mean age = 75 yrs) who underwent computer tomography (CT)-guided thermal ablation between October 2008 and March 2019. Tumor complexity was assessed by the RENAL nephrometry scoring system, wherein an RCC with a score greater than 10 is considered to be anatomically complex. The rate of complications, residual disease, and local recurrence were compared among radiofrequency ablation (RFA), microwave ablation (MWA) and cryoablation (CA), using the Chi-Square test. The Kaplan-Meier method was used to compute cancer-specific survival rates in each group, which were compared using the log-rank test.
Results: A total of 83 anatomically-complex RCC measuring between 1.9 to 5.2 cm in diameter were treated with CT-guided MWA (n = 20,24%), RFA (n = 57,69%) or CA (n = 6,7%). There was no significant difference in baseline patient or tumor demographics among the three groups. MWA is associated with significantly decreased ablation time (p = 0.001), procedural time (p = 0.001) and sedation dosage (p = 0.001), when compared to RFA and CA groups. All three ablative modalities resulted in similar rates of complications, residual disease and local recurrence (p= 0.07, p= 0.27, p= 0.10, respectively).
Conclusion: CT-guided MWA, RFA and CA resulted in comparable perioperative complications and treatment outcomes for anatomically complex RCC. The choice of ablative modality does not appear to impact local recurrence and survival outcomes for complex renal tumors.