The pendulum has now completely swung, and currently more PNs are performed than radical nephrectomies for SRMs. There is also a trend toward robotic/laparoscopic surgery vs. open surgery (60% vs. 40%). Due to advances in descriptive techniques, such as nephrometry scoring systems, we are now in the midst of a debate about the complexity of tumors that are amenable to PN.
There are multiple ways to perform a PN (enucleation, wedge resection, heminephrectomy, etc …). Evidence shows that simple enucleation appears to have similar oncologic outcomes as wider resections, but this is up to some debate. A major advancement in PN has been the use of intraoperative ultrasound, which gives finer detail of tumor characteristics prior to beginning to cut. Evidence shows that intraoperative ultrasound frequently changes management during surgery, so its use is important.
Chronic complications following OPN can be surgical or medical. Common surgical complications such as hernias, urinary fistulas, and bleeding can occur. However almost 50% of complications are medical (renal failure, MI, DVT, PE). Studies also clearly show that complications such as intraoperative blood loss and rates of renal insufficiency decrease with time, so experience is clearly important to the reduction of complications in these patients. Indeed, OPN complication rates now approach the complication rates of radical nephrectomy; the takeaway being that OPN should really be considered a safe procedure with current techniques.
Only one prospective randomized trial has been performed (EORTC Intergroup Phase 3 study of PN vs. radical nephrectomy in SRMs <5cm. The study showed that the rates of complications following PN are slightly higher than those following RN, especially for bleeding, urinary fistula, and reoperation rates. So while OPN is clearly a safe procedure, one must still consider the possibility of these complications prior to undertaking PN. There is also good evidence now that minimally invasive approaches have improved morbidity profiles over OPN, so when possible, minimally invasive surgery should be offered.
Dr. Volpe opined on several common complications following PN.
- 1. Urine leak – Always consider placing an intraoperative stent, especially if major reconstruction is needed. Always place a drain for larger and central tumors that are likely to give rise to a leak.
- 2. Bleeding – Bleeding can be acute or delayed. Sometimes it requires embolization. The use of hemostatic agents has not shown to be significantly more effective than no product.
- 3. Chronic renal insufficiency – Limit warm ischemia to <30 min. Preservation of renal parenchyma is now clearly understood to be the most important aspect of preventing chronic renal insufficiency. Vigorously hydrate the patient. Avoid reperfusion injury from repeat clamping. Be prepared to perform intraoperative hypothermia, if possible. EORTC data shows that <5% of patients end up with significant long term renal insufficiency, but these patients generally have multiple medical comorbidities.
Presented by: Alessandro Volpe, MD. Novara, Italy
Written by: Shreyas Joshi, MD, Fox Chase Cancer Center, Philadelphia, PA at the 2018 European Association of Urology Meeting EAU18, 16-20 March, 2018 Copenhagen, Denmark