**3.3.4 PSM**

342 Chronic Kidney Disease

The sole significant risk factor for overall complications was the cortico-medullar location of

In the same study of Porpiglia (Porpiglia et al., 2010), small and large tumours groups had comparable preoperative serum creatinin and estimated GFR. On the 5th post-operative day, elevation of serum creatinin level was not significantly higher in the large tumour

The size of the tumour had no significant impact on the warm ischemia time (Porpiglia et

In large tumours, they recorded 4 cases (12%) with CKD progression, but these could not be

Comparable to Russo in open partial nephrectomy, Porpiglia (Porpiglia et al., 2010) had a higher PSM rate in small tumours. Thus it appears that, as seen in open NSS, tumour size

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

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

group, but deterioration of eGFR was statistically significant (p > 0.004).

the tumour (Porpiglia et al., 2010).

al., 2010).

et al., 2010).

**3.3.1 Surgical aspects** 

upper pole tumours.

**3.2.3.2 Impact of tumour size on renal function** 

explained by a longer warm ischemia time.

**3.2.3.3 Impact of tumour size on oncologic outcome** 

does not impact on PSM risk in the laparoscopic approach.

**3.3 Robot-assisted laparoscopic partial nephrectomy** 

**3.3.1.1 Retroperitoneal or transperitoneal approach** 

Benway (Benway et al., 2010) compared 118 LPN and 129 RAPN: the PSM rates were 0.8% and 3.9%, respectively. The PSM rate was higher in RAPN, however this was not significant (p=0.11). Wang (Wang & Bhayani, 2010) reviewed 100 LPN versus 100 RAPN and also noted no significant differences in PSM rate. Benway (Benway et al., 2010), in a review of 183 RAPN, described 3.8% PSM. Gill (Gill et al., 2007) reported a PSM rate of 2.85% in LPN versus 1.26% in open procedures. Kural (Kural et al., 2009) reported no PSM but his study contained only 10 RAPN. On his 71 RAPN, Patel (Patel et al., 2010) had no PSM in 15 tumours larger than 4 cm and 3 PSM on 56 smaller tumours. To our knowledge, no study showed an increased PSM rate in tumours measuring between 4 and 7 cm.

### **3.3.5 Renal function**

Having a tumour larger than 4 cm was not significantly predictive of an increased risk of kidney function loss at the first post- operative day or at 1-3 month follow-up. However, only 9 tumours larger than 4 cm and 28 smaller tumours were included (Patel et al., 2010)
