Robotic Partial Nephrectomy in the Treatment of Renal Angiomyolipoma

To present the experience and efficacy of Robotic Partial Nephrectomy (RPN) for the management of renal angiomyolipomas (AMLs) with regard to renal function preservation and perioperative outcomes.

We retrospectively searched our RPN database for pathologically confirmed renal AML patients between 2006 and 2014. Clinical presentation, perioperative complications, and postoperative outcomes of the patients were analyzed. Preoperative imaging findings were reviewed to examine their ability to predict pathology of AML.

From 1005 RPN performed in our center during the study period, 53 patients met our inclusion criteria. The mean age at presentation was 54.1 (± 13) years, and 42 (79.2%) patients were female. Median tumor size was 2.8 (interquartile range [IQR], 1.8-4.6) cm. The indication for RPN was suspicious radiologic features for malignancy in 42 (79.2%) patients and acute retroperitoneal hemorrhage risk and pain in 11 (20.8%) patients who were found to have AML according to preoperative imaging. Mean estimated blood loss was 198 (± 194) mL, and 5 (9.4%) patients required blood transfusion. Postoperative complications occurred in 8 (15%) patients. Median estimated glomerular filtration rate within the latest follow-up was 86.9 (IQR, 69.7-100.1) mL/minute/1.73 m(2) with a median of 91% (IQR, 80.4-103) preservation. None of patients developed urinary fistula or pseudoaneurysm requiring second intervention. No local recurrences occurred with a median follow-up of 7 (IQR, 1-17) months.

Given the low complication rate and preservation of renal function after RPN for AML, it can be considered a reliable method for AML treatment. The majority of AMLs were not suspected based on preoperative imaging. Further diagnostic methods are needed to differentiate benign from malignant lesions.