To report experience with 100 robot-assisted partial nephrectomy (RAPN) operations performed at our institution. Nephron-sparing surgery is an established treatment for patients with small renal masses. The laparoscopic approach has emerged as an alternative to open nephron-sparing surgery, but it is recognized to be technically challenging. The robotic surgical system may enable faster and greater technical proficiency, facilitating a minimally invasive approach to more difficult lesions while reducing ischemia time.

A total of 100 RAPN operations were performed for suspicious solid renal lesions during a 21-month period. Clinicopathologic variables, nephrometry scores, operative parameters, and renal functional outcomes were prospectively recorded and analyzed.

Median tumor size was 2.8 cm (range, 1.0-8). Nephrometry scores of resected lesions were low in 47.9% of patients, medium in 45.7%, and high in 6.4% of patients. Forty-seven percent of patients had tumors >50% intraparenchymal, and 61.7% had tumors located less than 7 mm away from the renal sinus or collecting system. In 17% of patients, the tumors were touching a first-order vessel in the renal hilum. Mean warm ischemia time was 25.5 minutes (range, 0-53). Mean change in postoperative glomerular filtration rate improved 6.32 mL/min/1.73 m² (range, −41.9 to 68.9). Histology was renal cell carcinoma in 81% (87/107) of tumors. There were 5 microscopically positive margins on final pathology (5.7%). Major and minor complication rates were 6% and 5%, respectively. There were 2 conversions to open surgery.

RAPN seems to be a safe and technically feasible minimally invasive approach to nephron-sparing surgery even in more complex cases, with acceptable pathologic and renal function outcomes.