Introduction: The surgical paradigm for small renal masses has evolved towards less invasive nephron sparing intervention. While partial nephrectomy remains the gold standard for the management of most small renal masses, increasing experience with renal cryoablation has suggested a viable alternative with a favorable morbidity profile and good efficacy. We compare intermediate-term oncologic outcomes following laparoscopic partial nephrectomy (LPN) and renal cryoablation (RC) from a multi-center experience.
Methods: We performed a retrospective review of our LPN and RC experience between 9/1998 and 3/2008. Patients with at least 6 months follow-up were included in the analysis. LPN was performed via a transperitoneal approach. RC was performed via a percutaneous or transperitoneal laparoscopic approach. Follow-up consisted of imaging and laboratory studies at regular intervals. Persistent mass enhancement or interval tumor growth was considered a treatment failure following RC, and repeat biopsy and retreatment were recommended. Residual enhancing tumor was evidence of treatment failure following LPN.
Results: 119 patients (60%male, 39%black, mean BMI: 29.3) underwent RC with a mean follow-up of 29.5 months (range: 7-120). 123 patients (41%male, 34%black, mean BMI: 27.5) underwent LPN with a mean follow-up of 23.8 months (range: 7.7-74.6). Average patient age was 58 for LPN and 68 for RC (p<0.001). Overall, co-morbid conditions were prevalent with 20% DM, 61% HTN, and 68% smoking history in the LPN cohort and 24% DM (p=0.40), 78% HTN (p<0.05), and 53% smoking history (p<0.05) in the RC cohort. Mean tumor size was 2.7cm for LPN and 2.6cm for RC (p=0.84). 70% of LPN specimens were RCC while 48% of RC were biopsy-confirmed RCC (p=0.001). 5 positive margins were reported in the LPN cohort. Local failures after primary RC were successfully salvaged with repeat RC in 8 patients. Disease free survival was 99% in the LPN cohort with only 1 local recurrence and no metastatic recurrences. Disease free survival in the RC cohort was 97% with 4 patients having evidence of disease at last follow-up (p=0.19). Overall survival was 96% and 97% in the LPN and RC cohorts, respectively (p=0.71).
Conclusions: Intermediate oncologic outcomes appear to be nearly equivalent in this multi-center study of well-matched LPN and RC cohorts. RC had higher primary treatment failure rates than LPN, but salvage retreatment afforded statistically equivalent overall cancer-free survival.
Session: Podium Presentation
Program Number: S007