Partial nephrectomy is also referred to as "nephron-sparing surgery" or "kidney-sparing surgery." During partial nephrectomy the surgeon removes the tumor and saves the kidney. This is a delicate procedure that requires an experienced surgeon and surgical team.
Not all partial nephrectomy procedures are the same. For example, surgeon may cut half the kidney for a very small 1 cm tumor while another may be able to save 90 percent of the kidney—a significant difference for your kidney health. Additionally, partial nephrectomy can be performed via open or robotic-assisted laparoscopic surgery and a surgeon trained and experienced in both techniques is ideal. There are many other critical variables involved that are best handled by an experienced team.
Am I not better off by removing my entire kidney and being safe?
Not necessarily. Studies have shown that a partial nephrectomy can remove the tumor and achieve results similar to total kidney removal. This has been well established for tumors less than four cm and there is emerging research suggesting that the same is true for larger tumors.
An experienced surgeon can look at the CT or MRI scan and make an assessment regarding the feasibility and safety of a partial nephrectomy. Less experienced surgeons may erroneously decide that it is best to take out the entire kidney. Partial nephrectomy is a relatively rare complex procedure and there is no substitute for experience in helping make the right decision.
What is the benefit of a partial nephrectomy?
The major advantage is preserving kidney function. According to a classic study published in the New England Journal of Medicine*, patients who have poor kidney function are more likely to suffer from heart disease and die from it. Additionally, a recent study in the Journal of the American Medical Association** verifies that partial nephrectomy patients live longer than patients who have had total kidney removal. These results, while important, may not apply to everyone and thus the benefit for you personally should be discussed with your urologist.
*(Go AS, Chertow GM, Fan D, McCulloch CE, Hsu CY. Chronic kidney disease and the risks of death, cardiovascular events, and hospitalization. N Engl J Med. 2004 Sep 23;351(13):1296-305.)
**(Tan HJ, Norton EC, Ye Z, Hafez KS, Gore JL, Miller DC. Long-term survival following partial vs radical nephrectomy among older patients with early-stage kidney cancer. JAMA. 2012 Apr 18;307(15):1629-35.)
Who is the ideal partial nephrectomy patient?
First and foremost, the tumor must be in a location that would make a partial nephrectomy feasible and safe. Experienced surgeons specializing in partial nephrectomy have the best chance at removing difficult tumors successfully.
These are ideal patient characteristics:
- A patient who already suffers from kidney failure. If this patient loses a kidney he/she are more likely to require dialysis—which will result in a worsened quality (and potentially quantity) of life.
- A patient who has tumors in both kidneys. Saving one or both kidneys will help this patient avoid kidney failure as well.
- A patient who has risk factors for kidney failure. The most common reasons patients have poor kidney function today are diabetes and high blood pressure. Having these conditions means you may already have worse kidney function than you think. Saving the kidney will maintain a better kidney function and prevent kidney failure in the future.
- A patient who has kidney stones. If you have one kidney and a stone decides to pass and block the ureter it becomes a medical emergency. The blockage not only harms your remaining kidney and but blocks any urine from going through to your bladder.
- Any patient in whom the tumor can be safely removed via partial nephrectomy. Since we do not know what the future may bring, saving the kidney is usually preferable. Again, for certain patients this may not be desirable and a discussion with an expert urologist is necessary.
How is a partial nephrectomy performed?
The surgeon exposes the kidney and performs a thorough evaluation of it. After verifying that there are no other tumors in the kidney and that there is no spread of the tumor, the surgeon then cuts out the tumor and then reconstructs the kidney. An intraoperative ultrasound is usually performed to verify tumor location and configuration. We usually cut the tumor out and biopsy the surface left behind. This is verified to be "clean" before concluding the procedure to ensure that the tumor is completely removed.
Do most urologists perform partial nephrectomy?
Kidney tumors are rare and small kidney tumors are even rarer. Surgeons who routinely perform partial nephrectomy are thus exceedingly rare. Studies estimate that partial nephrectomy is underutilized due to the skills set and experience required to be comfortable with this advanced procedure.
Surgeons have traditionally removed the entire kidney as this is an easier procedure to master. Experienced partial nephrectomy experts rarely have to remove the entire kidney in this setting. For small kidney tumors (less than 4 cm), our experts perform a partial nephrectomy more than 90 percent of the time when surgery is undertaken. It remains that for the rare tumor, it might be technically impossible to save the kidney. Two surgeons may disagree on what constitutes a tumor that can be removed via partial nephrectomy. We advise that you consult with an expert before making a decision.
Are there any complications that can occur unique to a partial nephrectomy?
Since the kidney is left in place the raw surface where the tumor was cut can bleed. A delayed bleed occurs rarely (one percent to two percent of the time). Signs and symptoms of this are severe flank or abdominal pain, bruising on the side, or blood in the urine. Treatment for this is usually conservative (bedrest or a radiology procedure called embolization in the event of a pseudoaneurysm). A recent multi-institutional study headed by Johns Hopkins urologists revealed that this complication can usually be managed with a radiology procedure called selective angioembolization.* While rarely required, it is best that you ensure that your care team/hospital are experienced with this rare procedure.
*(Hyams ES, Pierorazio P, Proteek O, Sukumar S, Wagner AA, Mechaber JL, Rogers C, Kavoussi L, Allaf M. Iatrogenic vascular lesions after minimally invasive partial nephrectomy: a multi-institutional study of clinical and renal functional outcomes. Urology. 2011 Oct;78(4):820-6. Epub 2011 Aug 2.)
Another rare but unique complication is a urine leak. Urine can find its way out of the hole that is made by cutting the tumor out. Despite all efforts to seal the kidney at the time of surgery about one percent of the time a urine leak will occur. If this occurs, it usually seals on its own. Sometimes a ureteral stent (a straw-like structure placed in the ureter) is required to create a path of least resistance down the ureter rather than through the cut surface of the kidney.
These two complications do not occur when the entire kidney is removed. Recent Johns Hopkins studies reveal that these complications are exceedingly rare in our patients.
Is there a minimally invasive way to perform partial nephrectomy?
Yes. Johns Hopkins urologists have been performing minimally invasive partial nephrectomy since the early 1990’s. We have one of the largest and longest experiences with these procedures.* Most recently, research from our institution revealed that robotic-assisted partial nephrectomy was associated with a shorter operation, less bleeding, and a shorter ischemia time than the standard laparoscopic approach.** Our surgeons are amongst the most experienced in the world with robotic-assisted partial nephrectomy.
*( Allaf ME, Bhayani SB, Rogers C, Varkarakis I, Link RE, Inagaki T, Jarrett TW, Kavoussi LR. Laparoscopic partial nephrectomy: evaluation of long-term oncological outcome. J Urol. 2004 Sep;172(3):871-3.)
**(Mullins JK, Feng T, Pierorazio PM, Patel HD, Hyams ES, Allaf ME. Comparative analysis of minimally invasive partial nephrectomy techniques in the treatment of localized renal tumors. Urology. 2012 Aug;80(2):316-22. Epub 2012 Jun 13.)
Should I have an open or robotic-assisted laparoscopic partial nephrectomy?
Both of these are excellent operations when performed by the appropriate expert. Unique to our center is that our surgeons are experts with both techniques. Thus we examine the patient and choose the best approach not biased by a limited skill set. Unique patient and tumor factors may make one approach more favorable and this decision is best made with an expert urologist.
In general the robotic approach yields smaller incisions,less postoperative pain, and a shorter hospital stay.Our open surgical technique is unique in that it employs a smaller incision than traditional open techniques and does not routinely involve removing a rib.
Our commitment is to provide the best care with the most minimally invasive approach while maximizing safety and effectiveness.
What is "ischemia time" and what do I need to know about it?
Ischemia time refers to the amount of time that the surgeon temporarily blocks the blood vessels going into the kidney. The vessels are blocked to allow cutting the tumor in a bloodless field which allows the surgeon to see well and keeps the operation safe. Occasionally the surgeon can cut the tumor without blocking the vessels (no ischemia). A shorter ischemia time is desirable but it is important not to obsess over this point as studies have questioned the significance of ischemia time in harming the kidney. It is generally agreed upon, however, that an ischemia time less than 45 minutes is probably safe—although a shorter period is highly desirable especially in patients with compromised kidney function. A recent Johns Hopkins study revealed that for robotic partial nephrectomy our average ischemia time is less than 15 minutes and for select patients, no ischemia time is required.*
*(Pierorazio PM, Patel HD, Feng T, Yohannan J, Hyams ES, Allaf ME. Robotic-assisted versus traditional laparoscopic partial nephrectomy: comparison of outcomes and evaluation of learning curve. Urology 2011 Oct;78(4):813-9. Epub 2011 Jul 29.)