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Perioperative, oncological and functional outcomes after robotic partial nephrectomy vs. cryoablation in the elderly:
Riccardo Bertolo1, Juan Garisto1, Sherif Armanyous2
1Glickman Urological and Kidney Institute, Department of Urology, Cleveland Clinic, Cleveland, OH.
Objective:
To compare perioperative, oncological and functional outcomes of robotic partial nephrectomy (RPN) versus cryoablation in elderly patients (>75 years old), accounting for patient's and tumor's related factors.
Methods:
Retrospective institutional review of 312 consecutive elderly patients (> 75 years old) who underwent RPN or cryoablation for renal mass (June 2006-December 2016). Demographic, perioperative, functional, and oncological data were evaluated. Sixty-five patients who underwent RPN were propensity-score matched 1:1 to 65 who underwent cryoablation (matching was based on demographics, renal function, comorbidities and tumor characteristics). Perioperative outcomes were compared. Survival analysis was performed to estimate overall (OS), recurrence-free (RFS) and cancer-specific survival (CSS) by Kaplan-Meier method. A linear mixed effect model (LME) estimated the effect of follow-up on estimated glomerular filtration rate (eGFR).
Results:
After matching, the variables were well balanced with no differences at baseline between groups. Shorter operative time and lower blood losses favored cryoablation (140 vs. 200 min, P < 0.0001 and 100 vs. 195 ml, P = 0.0002, respectively). Overall complications rate was higher for RPN (31% vs. 9%; P = 0.007), but no difference was found in major (Clavien III-IV) complications (6% vs. 1.5%, P = 0.2). At a median follow-up of 37 (29-44) and 46 (38-53) months for RPN and cryoablation, no significant differences were found in CSS (100% vs. 95%, P = 0.3) and OS (80% vs. 75%, P = 0.2) but RFS was higher for RPN (100% vs. 83%, RPN vs. cryoablation, respectively, P = 0.02). eGFR was comparable between the groups at every time point analyzed.
Conclusions:
Although with a higher rate of recurrences, our data confirm cryoablation as a lower morbidity profile treatment option for small renal masses in the elderly population, with cancer-specific survival comparable to surgery.
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