**3.3 Robot-assisted laparoscopic partial nephrectomy**

Laparoscopy causes less morbidity than a flank incision. Robotic assistance is useful for suturing and tying (Weizer et al., 2011). This technique combines the minimally invasive approach of laparoscopy with the freedom of movement and dexterity acquired with the robot. Preliminary results with robotic NSS are comparable to results obtained with LPN (Van Poppel, 2010). With similar oncologic outcomes, the robotic approach seems to have a shorter learning curve compared to laparoscopic approach. It offers other benefits: lower intra-operative blood loss, reduced hospital stay and shorter warm ischemia time (Benway et al., 2010).

### **3.3.1 Surgical aspects**

#### **3.3.1.1 Retroperitoneal or transperitoneal approach**

The retroperitoneal access has the advantage of reducing the risk of intraperitoneal urine leak, intestinal lesions and future adhesions. Robot-assisted Retroperitoneal Partial Nephrectomy (RRPN) is indicated for posterior, interpolar or lower pole tumours. Morbid obesity and previous intra-abdominal surgery are no contra-indications. One major disadvantage of the retroperitoneal approach is the smaller working space, requiring a good coordination and more help from the assistant. Weizer (Weizer et al., 2011) described 2 conversions in 16 RRPN : one to conventional laparoscopy (difficulty of positioning robot's arms) and one to a transperitoneal approach because of peritoneal perforation. Six complications occurred: musculo-skeletal pain in one, 2 pneumonias, one urinary retention, one urinary fistula, one atrial fibrillation. In this study, all tumours were smaller than 3.5 cm. A retroperitoneal approach does not seem indicated for T1b tumours. The transperitoneal approach is preferred for tumours larger than 4 cm and upper pole tumours.
