Nephroureterectomy




Urothelial carcinoma can arise from any part of urothelium: bladder, renal collecting system, or ureter. The nomenclature of upper tract urothelial carcinoma (UTUC) is reserved for tumors that are localized to renal calyces or ureter. This is a relatively rare disease, representing only 5% to 10% of all urothelial cancers.


Reports from multiple comparative and one randomized study describe similar oncologic outcomes for laparoscopic and open extirpative surgery, with reduced perioperative morbidity favoring a laparoscopic approach. Because most upper tract urothelial tumors are not large or bulky, laparoscopic surgery is ideal for most patients, at least for the renal portion of a radical nephroureterectomy when the tumor warrants removal of the entire renal unit. There has been a recent shift in the paradigm for treatment of low-grade and low-stage tumors, for which consideration of endoscopic treatment may be given, but this discussion is beyond the scope of the chapter.


Once the extirpative management has been chosen, the surgical approach should be planned in a way that does not compromise oncologic control because UTUC is rarely able to be salvaged by adjuvant modalities. Accordingly, removal of an intact specimen is desirable to minimize the risk of tumor seeding from both the ureter and bladder. Laparoscopic nephroureterectomy can be performed by transperitoneal, retroperitoneal, hand-assisted, and robotic-assisted approaches, which are mostly dictated by surgeon’s experience. In this chapter we describe the more widely used transperitoneal technique.


Indications and Contraindications


Radical nephroureterectomy with removal of bladder cuff is the gold standard for large, high-grade, and invasive urothelial tumors of the renal pelvis and proximal ureter. It is also a choice in the presence of large, multifocal, or rapidly recurring low-grade or noninvasive tumors.


Large bulky tumors with involvement of adjacent viscera or those cases requiring extended lymph node dissection in the hands of a less experienced laparoscopic surgeon may be better suited for the open approach. Other patient factors such as a prior history of ipsilateral or extensive abdominal surgery or the presence of a perinephric inflammatory process should prompt a consideration of a retroperitoneal or an open approach.




Patient Preoperative Evaluation and Preparation


The preoperative evaluation of a patient with a suspected upper tract tumor should include a complete history and physical examination and laboratory studies to include complete blood count, chemistry profile, and urine cytology. The upper tract collecting system should be evaluated by computed tomography (CT) urography, but if the patient is unable to undergo contrast administration owing to poor renal function or allergies, this may be replaced by a magnetic resonance imaging (MRI) urogram. If MRI is contraindicated or unavailable, CT without contrast or ultrasound of the kidneys supplemented with retrograde pyelography is an acceptable alternative. If a suspicious lesion is identified, a normal saline washing of the area is performed, followed by ureteroscopic biopsy of the tumor. Cystoscopy should always be performed to exclude bladder tumors.


In the setting of positive cytologic test results without an identifiable lesion, along with the upper tracts, one should consider the bladder and prostatic urethra as possible sites harboring cancer. If results of bladder evaluation were negative or if cytologic test results remain positive after successful treatment of the bladder, then one should proceed with evaluation of extravesical sites to include selective cytologic samples from each upper urinary tract as well as resection of a representative specimen of the prostatic urethra in men. Selective cytologic tests should preferably be done along with ureteroscopy to allow for direct visualization of the upper urinary tracts. However, because of the limitations of cytologic testing alone with false-positive results and the high risk for bilateral disease in the future, if selective cytologic test results are persistently positive in the absence of any ureteroscopic or radiographic findings or if the treatment is not well established, radical nephroureterectomy is not recommended.


Consideration of nuclear renal scan to evaluate the function of the contralateral kidney may help with the decision regarding an extirpative versus organ-sparing approach. Staging should include chest radiography or tomography and bone scan only in the presence of symptoms or elevated alkaline phosphatase or calcium. No bowel preparation is necessary, but the patient should be on a clear liquid diet the day before surgery.




Operating Room Configuration and Patient Positioning


The operating room configuration for laparoscopic or robotic-assisted surgery is illustrated in Figure 18-1 . The surgical team stands on the contralateral side of the patient, and the scrub technician stands at the foot of the patient’s bed to facilitate access to the instrument table. Two towers with monitors are positioned, one on each side of the patient, to maximize visualization of the surgical progress by everyone involved in the operating room patient care.




Figure 18-1


The surgeon and assistant stand on the contralateral side of the table with the scrub person at the foot of the table. Mayo, Mayo instrument table.


If a transurethral approach is desired for bladder cuff removal, the patient is initially placed in the dorsal lithotomy position. If open distal ureterectomy or total laparoscopic or robotic-assisted technique is desired, or after the completion of the cystoscopic part, the patient is placed supine with the ipsilateral hip and shoulder rotated approximately 20 degrees ( Fig. 18-2 ). The patient is secured to the table and can be easily moved from the flank position (nephrectomy portion) to the supine position (open portion) without repreparing the operative field. The table can be flexed to widen the distance between the costal margin and iliac crest, but we do not find this necessary in most cases. Once the patient is secured to the table, we test the stability of the position by rotating the table left and right. Finally, the ipsilateral flank and urethra are prepared and draped, and a Foley catheter is placed in the sterile field before insufflation of the abdomen.




Figure 18-2


For laparoscopic nephroureterectomy, the patient is placed in the supine position with the ipsilateral arm across the chest. The patient is secured to the table and may be rotated during the procedure to the contralateral side.




Trocar Placement


The abdomen is insufflated, and three or four trocars are placed as outlined in Figure 18-3, A and B, with the first usually being the lateral trocar. Subsequent trocars are placed under direct vision. With this configuration, the camera is kept at the umbilicus for the entire procedure. The upper midline and lateral trocars are used by the surgeon for the dissection of the kidney and the proximal half of the ureter. The lower midline and lateral trocars are used for the dissection of the distal ureter. On the left side, dissection of the distal ureter may require placement of the fourth trocar. A 3-mm trocar just below the xiphoid can be helpful in retracting the spleen and liver for left- and right-sided nephrectomy, respectively. In obese patients, shifting of the trocars may be necessary to achieve optimal visualization ( Fig. 18-3, C ). If a hand-assisted approach is chosen, the hand port site should be placed so that it can be used for the dissection of the distal ureter and open bladder cuff as indicated ( Fig. 18-3, D ).




Figure 18-3


The trocars are placed in the midline for most patients. Port placement: A, left nephroureterectomy; B, right nephroureterectomy. C, In obese patients, ports should be shifted laterally. D, For hand-assisted nephrectomy, hand port should be placed caudally to help with distal ureterectomy and bladder cuff excision.


For robotic-assisted surgery, proper port positioning is paramount to success ( Fig. 18-4 ). Docking the robot, the surgeon places the left arm in port 1 and the right arm in port 2; the fourth arm is placed in port 3 and used for retraction. Once the nephrectomy portion has been completed, the retraction instrument is moved to port 1 and left arm to port 3 for distal ureter and bladder cuff dissection.




Figure 18-4


In robotic-assisted nephroureterectomy, robotic arms can be shifted among ports for nephrectomy and distal ureterectomy or bladder cuff excision portions.




Procedure (See )


Nephrectomy with Mobilization of the Ureter


The peritoneum is incised along the white line of Toldt from the level of the iliac vessels to the hepatic flexure on the right and to the splenic flexure on the left ( Fig. 18-5 ). The colon is moved medially by releasing the renocolic ligaments while leaving the lateral attachments of the Gerota fascia in place to prevent the kidney from “flopping” medially. The colon mesentery should be mobilized medial to the great vessels to facilitate dissection of the ureter, renal hilum, and local lymph nodes as needed ( Fig. 18-6 ). To expose the renal hilum, on the right side, it is necessary to perform a Kocher maneuver to deflect the duodenum medially ( Fig. 18-7, A ); on the left side, mobilize the pancreatic tail. Division of the splenorenal ligament is imperative to avoid the injury to the spleen and achieve mobility of the upper pole of the kidney ( Fig. 18-7, B ). The proximal ureter is identified, just medial to the lower pole of the kidney, and dissected toward the renal pelvis, avoiding skeletonization and maintaining copious periureteral fat if any tumor is located in this area ( Fig. 18-8 ). If an invasive ureteral lesion is suspected, the dissection should include a wide margin of tissue. The renal hilum is identified, and its vessels are exposed with a combination of blunt and sharp dissection. The artery is ligated and divided by use of a stapling device with a vascular load or multiple clips. The renal vein is then divided in a similar fashion ( Fig. 18-9 ). With vascular control ensured, most prefer to ligate the ureter with a clip, and the kidney is dissected free outside the Gerota fascia. As described for nephrectomy, the adrenal gland does not need to be removed routinely. Adrenal gland removal should be considered for high-grade and invasive lesions in the vicinity of the adrenal gland. The ureteral dissection is continued distally as far as is technically feasible, keeping in mind that the ureteral blood supply is generally anteromedially located in the proximal third, medially located in the middle third, and laterally located in the distal third. If distal limits of the dissection are below the level of the iliac vessels ( Fig. 18-10 ), the remainder of the procedure can easily be completed through a lower abdominal incision. The specimen is placed in the pelvis, and the renal bed is inspected meticulously for bleeding.


Sep 11, 2018 | Posted by in ABDOMINAL MEDICINE | Comments Off on Nephroureterectomy
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