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Laparoscopic partial nephrectomy
International Journal of Surgery xxx (2016) 1e6
Contents lists available at ScienceDirect
International Journal of Surgery journal homepage: www.journal-surgery.net
Review
Laparoscopic partial nephrectomy Philip T. Zhao*, Lee Richstone, Louis R. Kavoussi The Arthur Smith Institute for Urology, Department of Urology, Hofstra Northwell School of Medicine, 450 Lakeville Road, New Hyde Park, NY 11040, USA
h i g h l i g h t s Imaging of the renal mass (CT or MRI) must be present at time of surgery to confirm laterality and facilitate intraoperative decision-making. For obese patients, all trocar ports can be shifted laterally to help facilitate visualization and mobilization of the kidney. Intraoperative laparoscopic ultrasonography plays a key role in identifying margin and depth of tumor and is critical in resection of larger and more endophytic lesions. Off-clamp approach is ideally used for smaller and peripheral lesions while selective arterial clamping and VMD can be applied for more hilar and central tumors. There is no known safe threshold of warm ischemia time as each minute sequentially contributes to risk of developing acute kidney injury and longterm decline. Renal function following LPN is dependent on quality, quantity, and quickness e Rule of three Q's.
a r t i c l e i n f o
a b s t r a c t
Article history: Received 4 January 2016 Received in revised form 9 April 2016 Accepted 10 April 2016 Available online xxx
Laparoscopic partial nephrectomy (LPN) compares favorably to traditional open nephron-sparing surgery (NSS) in terms of oncologic and surgical principles for kidney tumors. Studies have shown the modality to be feasible with similar oncologic efficacy and superior renal functional outcomes compared with laparoscopic radical nephrectomy (LRN) for tumors. The main advantages of LPN include marked improvements in estimated blood loss, decreased surgical site pain, shorter postoperative convalescence, better cosmesis, and nephron preservation. This review article evaluates the literature regarding LPN and discusses the main steps of the operation, the perioperative workup and management, surgical complications, and its role in the surgical management of kidney masses. © 2016 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.
Keywords: Laparoscopic partial nephrectomy Nephron-sparing surgery Kidney mass Kidney cancer Laparoscopy
1. Introduction Laparoscopic partial nephrectomy (LPN) compares favorably to traditional open nephron-sparing surgery (NSS) in terms of oncologic and surgical principles for kidney tumors [1e3]. Studies have shown the modality to be feasible with similar oncologic efficacy and superior renal functional outcomes compared with laparoscopic radical nephrectomy (LRN) for tumors up to pT3a [4]. The main advantages of LPN include marked improvements in estimated blood loss, decreased surgical site pain, shorter postoperative convalescence, better cosmesis, and nephron preservation [5]. Over the past decade, alternative modalities to LPN have been
* Corresponding author. E-mail address: [email protected] (P.T. Zhao).
established including laparoscopic ablative techniques and roboticassisted LPN (RALPN). However, recent studies have demonstrated that LPN has better long-term oncologic outcomes than laparoscopic cryoablation and better cost-efficacy compared with RALPN [6,7]. In experienced hands, LPN still serves as an excellent platform for NSS despite a more challenging learning curve [8]. The key principles and mainstays of LPN have remained the same regardless of modifications to the technique; these are early and secure vascular control, limited warm ischemia time (WIT), adequate postresection hemostasis, and renorrhaphy.
2. Indications and contraindications The indications for partial nephrectomy have expanded from the imperative setting to elective partial nephrectomy in the presence of a contralateral normal kidney. Go et al. demonstrated
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Please cite this article in press as: P.T. Zhao, et al., Laparoscopic partial nephrectomy, International Journal of Surgery (2016), http://dx.doi.org/ 10.1016/j.ijsu.2016.04.028
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P.T. Zhao et al. / International Journal of Surgery xxx (2016) 1e6
the association between a reduced estimated glomerular filtration rate (GFR) and the risk of death, cardiovascular events, and hospitalization in a large, community-based population and these findings have highlighted the clinical importance of chronic renal insufficiency [9]. Population-based studies have shifted the pendulum of renal intervention away from radical nephrectomy towards NSS in appropriately selected patients [10]. Indications also include cases of hereditary renal cell carcinoma (RCC), such as von Hippel-Lindau syndrome, hereditary papillary RCC, and Birt syndrome, where the risk of future development of Hogg- Dube additional renal lesions after surgery is high. With advancement in technique and more experience, the indications of LPN have expanded beyond small (<4 cm), exophytic, and peripheral renal masses to include more technically difficult cases. Hilar and deep infiltrating tumors in additional to tumors in solitary kidneys and larger or cystic lesions are no longer considered relative contraindications to the procedure [5,11]. Contraindications that remain include renal vein or inferior vena caval (IVC) thrombi and significant local tumor invasion; however, in expert hands such cases can be performed [12]. Significant local tumor invasion, uncorrected coagulopathy, and inability to safely perform laparoscopy from intra-abdominal adhesions are additional contraindications. Moderate to complete renal insufficiency is a relative contraindication to complete hilar clamping. 3. Preoperative imaging Imaging studies including abdominal and pelvic computed tomography (CT), with or without three-dimensional reconstruction, or magnetic resonance imaging (MRI) should be part of standard workup of the renal mass. If renal function is adequate, intravenous or gadolinium contrast should be administered to better define the characteristics of the renal mass as well as the vasculature. It is important to delineate tumor location, its relationship to the pelvicaliceal collecting system, and the hilar vessel architecture. The renal vein of the affected kidney and the IVC must be evaluated to be free of tumor thrombus. Sometimes MRI can better characterize tumor thrombus. Additional imaging of the chest (CT or chest Xray), bone scan, head CT or MRI should be performed based on clinical indications in the overall workup of the patient. For centrally located tumors and for patients with hematuria, urothelial cell carcinoma must be ruled out prior to embarking on LPN. It is imperative imaging of the renal mass is present at time of surgery to confirm laterality and facilitate intraoperative decision-making. 4. Operating room configuration and patient positioning The laparoscopic approach to be used will determine the operating room configuration. Standard ergonomics dictate the anesthesiologist and anesthesia machines to be located at the head of the patient and the scrub nurse and instrument trays to be at the foot. Sometimes the equipment table is situated opposite the surgeon to facilitate passage of instruments, depending on surgeon preference and operating room space. The surgical approach will also dictate patient positioning. The decision to utilize the retroperitoneal approach as opposed to the transperitoneal one is based on surgeon preference and judgment based on cross-sectional imaging. In general, a rule of thumb to determine posteriority of a kidney mass is to draw a straight line medial-to-lateral from the renal hilum to the most convex point on the lateral aspect of the kidney. Any tumor located anterior to or crossing this line theoretically may be easier to approach transperitoneally, while any tumor completely posterior to this line may be easier to approach retroperitoneally. The transperitoneal approach is used more often because it is more familiar to most
urologists. The patient is placed in the modified lateral decubitus position, which allows the bowel to fall away from the kidney and site of dissection. The transperitoneal approach is performed at or between 45 and 60 of lateral tilt while the retroperitoneal approach is done at the full 90 tilt, which allows for easier establishment of retropneumoperitoneum. The patient should be rolled with the correct surgical side up and supported with gel rolls behind his or her back. The operating table can be flexed to maximize the space between the iliac crest and lowermost rib; however, it is rarely necessary for the transperitoneal approach. In any case, emphasis is placed on careful placement of foam padding at soft tissue and bony sites of pressure. This includes the head and neck, axilla, hip, knee, and ankle joints. Slight flexion at those joints can be provided to decrease the chance of inadvertent hyperextension during the surgery. A pillow is placed under both knees. An axillary roll is not required if the patient is tilted at the 45 angle and not lying directly on his or her axilla. The upper arm can be placed in a padded armrest or secured between foam cushions and placed away from the surgical site across the patient's chest with an upward bend at the elbow. The patient is completely secured to the operating table using safety belts or silk adhesive tape, taking care to cover the skin with protective towels at tape contact points. The table should be tilted prior to start of the operation to ensure the patient is appropriately secured. The ground-return pad should be affixed to the patient's thigh. Perioperative antibiotics, typically a first-generation cephalosporin when appropriate, should be administered within sixty minutes of surgical incision. Sequential compression devices are routinely used for deep venous thrombosis prophylaxis and subcutaneous heparin can be administered preoperatively in high thromboembolic risk patients. A Foley catheter and an oro- or nasogastric tube are placed preoperatively to maximize operating space and reduce potential for stomach and bladder injury. 5. Trocar placement Trocar positioning also depends on approach. A three-port placement technique is used for both transperitoneal and retroperitoneal approaches. For the transperitoneal approach, pneumoperitoneum is usually established by the closed (Veress) needle technique at the umbilicus. The primary port (10-mm) site is then placed lateral to the rectus muscle at the level of the umbilicus. A subcostal port (5-/10-mm) is placed lateral to the rectus muscle and slightly inferior to the costochondral margin. The more obese the patient, the more lateral these trocar ports are placed. In thin patients, the camera port can sit at the umbilicus and the subcostal port can sit in the midline just below the xiphoid process. A 12-mm working trocar is placed in the midclavicular line lateral to the camera port. When working on the right side, an additional 5-mm trocar cephalad to the subxiphoid trocar can be positioned for liver retraction. A fourth trocar, a 10- or 12-mm trocar, can be placed in the midline inferior to the umbilicus for additional access to retract the intestines medially or to place a Satinsky clamp placement if needed. This port can also be expanded to allow extraction of a larger specimen. 6. Intraperitoneal approach After establishment of pneumoperitoneum, the colon is medially reflected along the white line of Toldt. Depending on the operative side, the retroperitoneal space is entered by adequately releasing the splenorenal or hepatorenal ligaments. On the left side, more extensive mobilization of the splenic flexure, pancreas, and spleen is required as these structures cover almost the entire
Please cite this article in press as: P.T. Zhao, et al., Laparoscopic partial nephrectomy, International Journal of Surgery (2016), http://dx.doi.org/ 10.1016/j.ijsu.2016.04.028
P.T. Zhao et al. / International Journal of Surgery xxx (2016) 1e6
anterior aspect of Gerota's fascia. On the right side, the second portion of the duodenum is carefully Kocherized to expose the IVC. After the colon is mobilized and reflected, the avascular fascial plane between Gerota's fascia and the posterior mesocolon is identified and developed. Then the entire kidney is lifted upwards above this plane to identify the psoas muscle. The ureter and gonadal vein packet are found inferior to the lower pole and lateral to the ipsilateral great vessel. The gonadal vein can be ligated if interfering with the dissection, and otherwise it should be positioned medially below the site of dissection. The ureter and lower pole can be retracted upward and laterally, and traced back to the renal hilum. Dissection along the psoas muscle and lateral border of the ipsilateral great vessel leads to the renal vein and artery. The fascia overlying the psoas muscle should remain intact during the dissection. Usually, the plane between the upper pole of the kidney and the ipsilateral adrenal gland is freed to help facilitate mobilization of the kidney and better identification of the renal hilum. Once the renal vein and artery are found, they are dissected to the extent that a window superior and inferior to each of them is created that can easily accommodate one or two laparoscopic vascular bulldog clamps. Intraoperative ultrasound should be used to localize the lesion(s) and will help to ensure Gerota's fasica is entered away from the tumor when the kidney is defatted. Removing most of the fat from the renal surface serves to make the kidney more mobile and also allows more versatility for intraoperative ultrasound (US) viewing as well as tumor resection and suturing angles. Some fat is left on the tumor to serve as a handle during tumor resection and also to allow adequate pathological staging once the specimen is removed. Under real-time US, the proposed line for tumor excision can be circumferentially scored on the renal capsule with the
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monopolar scissor around the tumor. We clamp the renal artery alone with laparoscopic bulldog clamps prior to tumor resection (Fig. 1A). The renal artery is clamped alone as opposed to the arteryvein clamped en bloc because it is well established that applying artery-only clamping, especially in cases with prolonged ischemia time, lessened ischemic renal damage during LPN [13]. A 12.5-g dose of mannitol can be given intravenously prior to hilar clamping. This has been shown in animal studies to lessen renal damage during hypoxia. It is often helpful to place two bulldog clamps on the renal artery if renal artery length allows. The tumor is then excised with a combination of sharp dissection with the cold scissors and blunt dissection and countertraction with the suction-irrigator (Fig. 1B,C). Obvious arteries supplying the mass can be clipped with either metal clips or locking Hem-o-loc plastic clips (Teleflex, Research Triangle Park, NC, USA) as the tumor excision progresses (Fig. 1D). Once completely excised, the mass is then placed into a laparoscopic bag via the working port. The renal resection bed is then treated with the argon beam coagulator to aid with hemostasis (Fig. 2A). Renorrhaphy can be carried out in a variety of methods. We prefer to use a 3-0 V-Loc suture (Covidien, Mansfield, MA, USA) across the base of the resection to close any collecting system or vascular injuries (Fig. 2B,C). A Hem-o-loc clip is applied to each end of the running suture to exert tension at the closure base. A 20 V-Loc suture then follows in a continuous horizontal mattress fashion to reapproximate the renal parenchyma and complete the renorrhaphy. Alternatively, the outer renorrhaphy can be completed with a continuous running baseball stitch and a sliding Hem-o-loc clip after each wall-to-wall throw (Fig. 2D). Bulldog clamps can be removed after base suturing is completed to
Fig. 1. Arterial clamping and tumor resection.
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Fig. 2. Steps of renorrhaphy.
minimize warm ischemia. Following renorrhaphy, insufflation pressure is reduced to 5 mm Hg for 5e10 min to evaluate for surgical bleeding. Once hemostasis is ensured, the specimen is extracted after enlarging the camera port or working port incisions. A separate Pfannenstiel, Gibson, or lower midline incision can be made if the specimen is substantially large. The extraction site is determined by each surgeon's preference. A surgical drain is usually placed in the paracolic gutter adjacent to the kidney when the collecting system is entered during mass excision, although some authors contend that can be safely omitted given the low rates of urine leaks [14]. The 10- and 12-mm trocar sites are closed under direct laparoscopic vision. Pneumoperitoneum is released and all incision are closed at the skin level with subcuticular sutures and covered with bonding agent or adhesive strips. 6.1. Off-clamp (zero-ischemia) technique Off-clamp or “zero ischemia” approach to partial nephrectomy (PN) has been gaining popularity over the past several years and has been established to offer comparable perioperative safety, equivalent oncologic outcomes, and superior long-term renal function preservation when compared with on-clamp approach for RCC in appropriately selected patients [15]. Specifically for LPN, the technique avoids renal ischemic injury with the benefits of minimally invasive surgery for peripheral cT1-T2 tumors [16]. Traditionally, clamping the renal hilum during LPN allows for minimal blood loss and better visualization during dissection and renorrhaphy. However, renal ischemia and reperfusion injury is a consequence of hilar occlusion. As anticipated, using an off-clamp
technique during LPN has variably shown increased EBL when compared to hilar-controlled operations but this does not seem to translate into increased risk of transfusion or loss of visualization leading to compromise in oncologic outcomes [17].
6.2. Selective arterial clamping Gill et al. first described the technique of anatomic vascular microdissection (VMD) of renal artery branches to allow selective clamping of vessels to extend the application of zero-ischemia PN [18]. This allowed more complex tumors such as hilar, central, intrarenal, and polar lesions to be resected without global surgical renal ischemia. After exposure of the renal hilum, the main renal artery and vein are circumferentially mobilized and encircled with vessel loops. After assessing the patient's preoperative CTreconstructed 3-dimensional hilar architecture, microdissection is performed in a medial-to-lateral direction to identify the specific arterial branches supplying the tumor. Microsurgical bulldog clamps are used to clamp the targeted arterial branches and evaluation of the collateral kidney around the tumor is performed to confirm normal color and turgor. If there is concern the branch clamped has decreased perfusion to normal kidney, the bulldog is unclamped immediately. Arterial mapping with this superselective ligation approach is done until only branches to the tumor(s) are clamped and the rest of the kidney is free from ischemia. The use of a laparoscopic Doppler can also help with identification of target arterial branches; cessation of intratumor and peritumor arterial flow confirms that the correct arterial branch has been controlled.
Please cite this article in press as: P.T. Zhao, et al., Laparoscopic partial nephrectomy, International Journal of Surgery (2016), http://dx.doi.org/ 10.1016/j.ijsu.2016.04.028
P.T. Zhao et al. / International Journal of Surgery xxx (2016) 1e6
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7. Retroperitoneal approach
10. Oncologic outcomes
A retroperitoneal approach to laparoscopic partial nephrectomy is most beneficial for posteriorly located masses and in instances where considerable intraperitoneal adhesions are anticipated. Because of the limited working space and fewer familiar landmarks, the retroperitoneal approach can prove challenging in particularly obese patients with considerable retroperitoneal adiposity, and in patients with perirenal scar tissue from prior renal surgery or infections.
The trifecta of negative cancer margins, preserved renal function, and minimal perioperative complications e goals that are essential for open partial nephrectomy (OPN) e have been welltranslated to LPN across the urologic literature [20e22]. Positive surgical margins for most LPN series remain less than 1% with cancer-specific survival (CSS) of over 95% and 90% at ten years for cT1a and cT1b RCC, respectively [23]. The role and indications of LPN have been expanded to much more complex tumors e hilar, completely endophytic, and T1b and larger e and technical modifications have improved WIT and overall renal function preservation. LPN remains a valid alternative to OPN and a viable modality despite rapid technological advancements in robotics and ablative therapies.
8. Postoperative management Most institutions recommend 12e24 h of bed rest with patients ambulating by the morning of postoperative day one [17]. Some authors will recommend even earlier ambulation in order to prevent deep vein thrombosis. Both prophylactic doses of subcutaneous heparin as well as compression stockings should be applied immediately postoperatively. In patients at particularly high risk for DVT, preoperative prophylactic dosing of subcutaneous heparin or enoxaparin should be considered. In general, any oro- or nasogastric tube is removed prior to extubation and the patient is given a clear liquid diet in the recovery room once fully awakened from anesthesia. The diet is continued or advanced the next morning depending on clinical indications. The Foley catheter is kept overnight to measure outputs and removed the next morning. Drain output volumes are meticulously monitored after Foley removal because any significant increase may represent vesicoureteral reflux into a persistent or unrecognized collecting system injury. The creatinine concentration of the drain fluid is analyzed and compared to the serum creatinine level to assess for urine leak and to help determine the timing of drain removal. The Foley catheter may be reinserted if output from surgical drain is suggestive of urine leak and if volumes are significant. Most patient are discharged home postoperative day one or two without any external tubes. Patients are provided with a bowel regimen and narcotic pain medication to take as needed. For pT1 tumors, LPN patients are followed with abdominal imaging (CT or MRI) within three to twelve month postoperatively, in addition to chest X-ray and laboratory studies, as per AUA surveillance guidelines.
9. Surgical complications Intraoperative complications usually are associated with inadequate vascular control such as clamp failure, inability to identify and control multiple renal arteries, or poor haemostatic control during base-layer suturing and renorrhaphy. In larger studies, intraoperative hemorrhage can range as high as 3.5% and require conversion to open in 1% [19]. Additional less common injuries can occur to the ureter, bowel, spleen, liver and gallbladder, pancreas, and great vessels. Postoperative complications are typically related to bleeding or urine leak. Delayed spontaneous hemorrhage can occur up to 30 days postoperatively and has a reported frequency as high as 9.5%. The incidence of urine leak is approximately 4.5% [19]. Conservative management, selective angioembolization, or completion nephrectomy are the treatment options depending on clinical severity. Collecting system injuries rarely require reoperation with most resolving spontaneously and less than 10% needing urinary diversion (by either ureteral stent or percutaneous nephrostomy) [19].
Conflicts of interest None. Sources of funding None. Ethical approval N/A. Author contribution All authors contributed equally to study design and writing. This is a review paper, thus no data collection or analysis. Guarantor Philip Zhao, MD. References [1] B.R. Lane, S.C. Campbell, I.S. Gill, 10-year oncologic outcomes after laparoscopic and open partial nephrectomy, J. Urol. 190 (1) (2013) 44e49. [2] R.L. Favaretto, R. Sanchez-Salas, N. Benoist, et al., Oncologic outcomes after laparoscopic partial nephrectomy: mid-term results, J. Endourol. 27 (1) (2013) 52e57. [3] M. Marszalek, H. Meixl, M. Polajnar, et al., Laparoscopic and open partial nephrectomy: a matched-pair comparison of 200 patients, Eur. Urol. 55 (5) (2009) 1171e1178. [4] M.N. Simmons, C.J. Weight, I.S. Gill, Laparoscopic radical versus partial nephrectomy for tumors >4 cm: intermediate-term oncologic and functional outcomes, Urology 73 (5) (2009) 1077e1082. [5] H.S. Al-Qudah, A.R. Rodriguez, W.J. Sexton, Laparoscopic management of kidney cancer: updated review, Cancer Control 14 (3) (2007) 218e230. [6] T. Klatte, S.F. Shariat, M. Remzi, Systematic review and meta-analysis of perioperative and oncologic outcomes of laparoscopic cryoablation versus laparoscopic partial nephrectomy for the treatment of small renal tumors, J. Urol. 191 (5) (2014) 1209e1217. [7] E. Hyams, P. Pierorazio, J.K. Mullins, et al., A comparative cost analysis of robot-assisted versus traditional laparoscopic partial nephrectomy, J. Endourol. 26 (7) (2012) 843e847. [8] J.S. Ellison, J.S. Montgomery, J.S. Wolf Jr., et al., A matched comparison of perioperative outcomes of a single laparoscopic surgeon versus a multisurgeon robot-assisted cohort for partial nephrectomy, J. Urol. 188 (1) (2012) 45e50. [9] A.S. Go, G.M. Chertow, D. Fan, Chronic kidney disease and the risks of death, cardiovascular events, and hospitalization, N. Engl. J. Med. 351 (13) (2004) 1296e1305. [10] M. Daugherty, G. Bratslavsky, Compared with radical nephrectomy, nephronsparing surgery offers a long-term survival advantage in patients between the ages of 20 and 44 years with renal cell carcinomas (4 cm): an analysis of the SEER database, Urol. Oncol. 32 (5) (2014) 549e554. [11] B. Xu, Y. Mi, L.Q. Zhou, et al., Laparoscopic partial nephrectomy for multilocular cystic renal cell carcinoma: a potential gold standard treatment with excellent perioperative outcomes, World J. Surg. Oncol. 23 (12) (2014) 111.
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[12] R. Abaza, Robotic surgery and minimally invasive management of renal tumors with vena caval extension, Curr. Opin. Urol. 21 (2) (2011) 104e109. [13] Y. Funahashi, M. Kato, Y. Yoshino, et al., Comparison of renal ischemic damage during laparoscopic partial nephrectomy with artery-vein and artery-only clamping, J. Endourol. 28 (3) (2014) 306e311. [14] R. Abaza, D. Prall, Drain placement can be safely omitted after the majority of robotic partial nephrectomies, J. Urol. 189 (3) (2013) 823e827. [15] W. Liu, Y. Li, M. Chen, et al., Off-clamp versus complete hilar control partial nephrectomy for renal cell carcinoma: a systematic review and meta-analysis, J. Endourol. 28 (5) (2014) 567e576. [16] S. Rais-Bahrami, A.K. George, A.S. Herati, et al., Off-clamp versus complete hilar control laparoscopic partial nephrectomy: comparison by clinical stage, BJU Int. 109 (9) (2012) 1376e1381. [17] J.E. Kreshover, L.R. Kavoussi, L. Richstone, Hilar clamping versus off-clamp laparoscopic partial nephrectomy for T1b tumors, Curr. Opin. Urol. 23 (5) (2013) 399e402.
[18] C.K. Ng, I.S. Gill, M.B. Patil, et al., Anatomic renal artery branch microdissection to facilitate zero-ischemia partial nephrectomy, Eur. Urol. 61 (1) (2012) 67e74. [19] A.P. Ramani, M.M. Desai, A.P. Steinberg, et al., Complications of laparoscopic partial nephrectomy in 200 cases, J. Urol. 173 (1) (2005) 42e47. [20] A.J. Hung, J. Cai, M.N. Simmons, et al., “Trifecta” in partial nephrectomy, J. Urol. 189 (1) (2013) 36e42. [21] H. Zargar, M. Allaf, S. Bhayani, et al., Trifecta and optimal peri-operative outcomes of robotic and laparoscopic partial nephrectomy in surgical treatment of small renal masses: a multi-institutional study, BJU Int. 116 (3) (2015) 407e414. [22] A. Khalifeh, R. Autorino, S.P. Hillyer, et al., Comparative outcomes and assessment of trifecta in 500 robotic and laparoscopic partial nephrectomy cases: a single surgeon experience, J. Urol. 189 (4) (2013) 1236e1242. [23] B.R. Lane, S.C. Campbell, I.S. Gill, 10-year oncologic outcomes after laparoscopic and open partial nephrectomy, J. Urol. 190 (1) (2013) 44e49.
Please cite this article in press as: P.T. Zhao, et al., Laparoscopic partial nephrectomy, International Journal of Surgery (2016), http://dx.doi.org/ 10.1016/j.ijsu.2016.04.028
Contents lists available at ScienceDirect
International Journal of Surgery journal homepage: www.journal-surgery.net
Review
Laparoscopic partial nephrectomy Philip T. Zhao*, Lee Richstone, Louis R. Kavoussi The Arthur Smith Institute for Urology, Department of Urology, Hofstra Northwell School of Medicine, 450 Lakeville Road, New Hyde Park, NY 11040, USA
h i g h l i g h t s Imaging of the renal mass (CT or MRI) must be present at time of surgery to confirm laterality and facilitate intraoperative decision-making. For obese patients, all trocar ports can be shifted laterally to help facilitate visualization and mobilization of the kidney. Intraoperative laparoscopic ultrasonography plays a key role in identifying margin and depth of tumor and is critical in resection of larger and more endophytic lesions. Off-clamp approach is ideally used for smaller and peripheral lesions while selective arterial clamping and VMD can be applied for more hilar and central tumors. There is no known safe threshold of warm ischemia time as each minute sequentially contributes to risk of developing acute kidney injury and longterm decline. Renal function following LPN is dependent on quality, quantity, and quickness e Rule of three Q's.
a r t i c l e i n f o
a b s t r a c t
Article history: Received 4 January 2016 Received in revised form 9 April 2016 Accepted 10 April 2016 Available online xxx
Laparoscopic partial nephrectomy (LPN) compares favorably to traditional open nephron-sparing surgery (NSS) in terms of oncologic and surgical principles for kidney tumors. Studies have shown the modality to be feasible with similar oncologic efficacy and superior renal functional outcomes compared with laparoscopic radical nephrectomy (LRN) for tumors. The main advantages of LPN include marked improvements in estimated blood loss, decreased surgical site pain, shorter postoperative convalescence, better cosmesis, and nephron preservation. This review article evaluates the literature regarding LPN and discusses the main steps of the operation, the perioperative workup and management, surgical complications, and its role in the surgical management of kidney masses. © 2016 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.
Keywords: Laparoscopic partial nephrectomy Nephron-sparing surgery Kidney mass Kidney cancer Laparoscopy
1. Introduction Laparoscopic partial nephrectomy (LPN) compares favorably to traditional open nephron-sparing surgery (NSS) in terms of oncologic and surgical principles for kidney tumors [1e3]. Studies have shown the modality to be feasible with similar oncologic efficacy and superior renal functional outcomes compared with laparoscopic radical nephrectomy (LRN) for tumors up to pT3a [4]. The main advantages of LPN include marked improvements in estimated blood loss, decreased surgical site pain, shorter postoperative convalescence, better cosmesis, and nephron preservation [5]. Over the past decade, alternative modalities to LPN have been
* Corresponding author. E-mail address: [email protected] (P.T. Zhao).
established including laparoscopic ablative techniques and roboticassisted LPN (RALPN). However, recent studies have demonstrated that LPN has better long-term oncologic outcomes than laparoscopic cryoablation and better cost-efficacy compared with RALPN [6,7]. In experienced hands, LPN still serves as an excellent platform for NSS despite a more challenging learning curve [8]. The key principles and mainstays of LPN have remained the same regardless of modifications to the technique; these are early and secure vascular control, limited warm ischemia time (WIT), adequate postresection hemostasis, and renorrhaphy.
2. Indications and contraindications The indications for partial nephrectomy have expanded from the imperative setting to elective partial nephrectomy in the presence of a contralateral normal kidney. Go et al. demonstrated
http://dx.doi.org/10.1016/j.ijsu.2016.04.028 1743-9191/© 2016 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.
Please cite this article in press as: P.T. Zhao, et al., Laparoscopic partial nephrectomy, International Journal of Surgery (2016), http://dx.doi.org/ 10.1016/j.ijsu.2016.04.028
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P.T. Zhao et al. / International Journal of Surgery xxx (2016) 1e6
the association between a reduced estimated glomerular filtration rate (GFR) and the risk of death, cardiovascular events, and hospitalization in a large, community-based population and these findings have highlighted the clinical importance of chronic renal insufficiency [9]. Population-based studies have shifted the pendulum of renal intervention away from radical nephrectomy towards NSS in appropriately selected patients [10]. Indications also include cases of hereditary renal cell carcinoma (RCC), such as von Hippel-Lindau syndrome, hereditary papillary RCC, and Birt syndrome, where the risk of future development of Hogg- Dube additional renal lesions after surgery is high. With advancement in technique and more experience, the indications of LPN have expanded beyond small (<4 cm), exophytic, and peripheral renal masses to include more technically difficult cases. Hilar and deep infiltrating tumors in additional to tumors in solitary kidneys and larger or cystic lesions are no longer considered relative contraindications to the procedure [5,11]. Contraindications that remain include renal vein or inferior vena caval (IVC) thrombi and significant local tumor invasion; however, in expert hands such cases can be performed [12]. Significant local tumor invasion, uncorrected coagulopathy, and inability to safely perform laparoscopy from intra-abdominal adhesions are additional contraindications. Moderate to complete renal insufficiency is a relative contraindication to complete hilar clamping. 3. Preoperative imaging Imaging studies including abdominal and pelvic computed tomography (CT), with or without three-dimensional reconstruction, or magnetic resonance imaging (MRI) should be part of standard workup of the renal mass. If renal function is adequate, intravenous or gadolinium contrast should be administered to better define the characteristics of the renal mass as well as the vasculature. It is important to delineate tumor location, its relationship to the pelvicaliceal collecting system, and the hilar vessel architecture. The renal vein of the affected kidney and the IVC must be evaluated to be free of tumor thrombus. Sometimes MRI can better characterize tumor thrombus. Additional imaging of the chest (CT or chest Xray), bone scan, head CT or MRI should be performed based on clinical indications in the overall workup of the patient. For centrally located tumors and for patients with hematuria, urothelial cell carcinoma must be ruled out prior to embarking on LPN. It is imperative imaging of the renal mass is present at time of surgery to confirm laterality and facilitate intraoperative decision-making. 4. Operating room configuration and patient positioning The laparoscopic approach to be used will determine the operating room configuration. Standard ergonomics dictate the anesthesiologist and anesthesia machines to be located at the head of the patient and the scrub nurse and instrument trays to be at the foot. Sometimes the equipment table is situated opposite the surgeon to facilitate passage of instruments, depending on surgeon preference and operating room space. The surgical approach will also dictate patient positioning. The decision to utilize the retroperitoneal approach as opposed to the transperitoneal one is based on surgeon preference and judgment based on cross-sectional imaging. In general, a rule of thumb to determine posteriority of a kidney mass is to draw a straight line medial-to-lateral from the renal hilum to the most convex point on the lateral aspect of the kidney. Any tumor located anterior to or crossing this line theoretically may be easier to approach transperitoneally, while any tumor completely posterior to this line may be easier to approach retroperitoneally. The transperitoneal approach is used more often because it is more familiar to most
urologists. The patient is placed in the modified lateral decubitus position, which allows the bowel to fall away from the kidney and site of dissection. The transperitoneal approach is performed at or between 45 and 60 of lateral tilt while the retroperitoneal approach is done at the full 90 tilt, which allows for easier establishment of retropneumoperitoneum. The patient should be rolled with the correct surgical side up and supported with gel rolls behind his or her back. The operating table can be flexed to maximize the space between the iliac crest and lowermost rib; however, it is rarely necessary for the transperitoneal approach. In any case, emphasis is placed on careful placement of foam padding at soft tissue and bony sites of pressure. This includes the head and neck, axilla, hip, knee, and ankle joints. Slight flexion at those joints can be provided to decrease the chance of inadvertent hyperextension during the surgery. A pillow is placed under both knees. An axillary roll is not required if the patient is tilted at the 45 angle and not lying directly on his or her axilla. The upper arm can be placed in a padded armrest or secured between foam cushions and placed away from the surgical site across the patient's chest with an upward bend at the elbow. The patient is completely secured to the operating table using safety belts or silk adhesive tape, taking care to cover the skin with protective towels at tape contact points. The table should be tilted prior to start of the operation to ensure the patient is appropriately secured. The ground-return pad should be affixed to the patient's thigh. Perioperative antibiotics, typically a first-generation cephalosporin when appropriate, should be administered within sixty minutes of surgical incision. Sequential compression devices are routinely used for deep venous thrombosis prophylaxis and subcutaneous heparin can be administered preoperatively in high thromboembolic risk patients. A Foley catheter and an oro- or nasogastric tube are placed preoperatively to maximize operating space and reduce potential for stomach and bladder injury. 5. Trocar placement Trocar positioning also depends on approach. A three-port placement technique is used for both transperitoneal and retroperitoneal approaches. For the transperitoneal approach, pneumoperitoneum is usually established by the closed (Veress) needle technique at the umbilicus. The primary port (10-mm) site is then placed lateral to the rectus muscle at the level of the umbilicus. A subcostal port (5-/10-mm) is placed lateral to the rectus muscle and slightly inferior to the costochondral margin. The more obese the patient, the more lateral these trocar ports are placed. In thin patients, the camera port can sit at the umbilicus and the subcostal port can sit in the midline just below the xiphoid process. A 12-mm working trocar is placed in the midclavicular line lateral to the camera port. When working on the right side, an additional 5-mm trocar cephalad to the subxiphoid trocar can be positioned for liver retraction. A fourth trocar, a 10- or 12-mm trocar, can be placed in the midline inferior to the umbilicus for additional access to retract the intestines medially or to place a Satinsky clamp placement if needed. This port can also be expanded to allow extraction of a larger specimen. 6. Intraperitoneal approach After establishment of pneumoperitoneum, the colon is medially reflected along the white line of Toldt. Depending on the operative side, the retroperitoneal space is entered by adequately releasing the splenorenal or hepatorenal ligaments. On the left side, more extensive mobilization of the splenic flexure, pancreas, and spleen is required as these structures cover almost the entire
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anterior aspect of Gerota's fascia. On the right side, the second portion of the duodenum is carefully Kocherized to expose the IVC. After the colon is mobilized and reflected, the avascular fascial plane between Gerota's fascia and the posterior mesocolon is identified and developed. Then the entire kidney is lifted upwards above this plane to identify the psoas muscle. The ureter and gonadal vein packet are found inferior to the lower pole and lateral to the ipsilateral great vessel. The gonadal vein can be ligated if interfering with the dissection, and otherwise it should be positioned medially below the site of dissection. The ureter and lower pole can be retracted upward and laterally, and traced back to the renal hilum. Dissection along the psoas muscle and lateral border of the ipsilateral great vessel leads to the renal vein and artery. The fascia overlying the psoas muscle should remain intact during the dissection. Usually, the plane between the upper pole of the kidney and the ipsilateral adrenal gland is freed to help facilitate mobilization of the kidney and better identification of the renal hilum. Once the renal vein and artery are found, they are dissected to the extent that a window superior and inferior to each of them is created that can easily accommodate one or two laparoscopic vascular bulldog clamps. Intraoperative ultrasound should be used to localize the lesion(s) and will help to ensure Gerota's fasica is entered away from the tumor when the kidney is defatted. Removing most of the fat from the renal surface serves to make the kidney more mobile and also allows more versatility for intraoperative ultrasound (US) viewing as well as tumor resection and suturing angles. Some fat is left on the tumor to serve as a handle during tumor resection and also to allow adequate pathological staging once the specimen is removed. Under real-time US, the proposed line for tumor excision can be circumferentially scored on the renal capsule with the
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monopolar scissor around the tumor. We clamp the renal artery alone with laparoscopic bulldog clamps prior to tumor resection (Fig. 1A). The renal artery is clamped alone as opposed to the arteryvein clamped en bloc because it is well established that applying artery-only clamping, especially in cases with prolonged ischemia time, lessened ischemic renal damage during LPN [13]. A 12.5-g dose of mannitol can be given intravenously prior to hilar clamping. This has been shown in animal studies to lessen renal damage during hypoxia. It is often helpful to place two bulldog clamps on the renal artery if renal artery length allows. The tumor is then excised with a combination of sharp dissection with the cold scissors and blunt dissection and countertraction with the suction-irrigator (Fig. 1B,C). Obvious arteries supplying the mass can be clipped with either metal clips or locking Hem-o-loc plastic clips (Teleflex, Research Triangle Park, NC, USA) as the tumor excision progresses (Fig. 1D). Once completely excised, the mass is then placed into a laparoscopic bag via the working port. The renal resection bed is then treated with the argon beam coagulator to aid with hemostasis (Fig. 2A). Renorrhaphy can be carried out in a variety of methods. We prefer to use a 3-0 V-Loc suture (Covidien, Mansfield, MA, USA) across the base of the resection to close any collecting system or vascular injuries (Fig. 2B,C). A Hem-o-loc clip is applied to each end of the running suture to exert tension at the closure base. A 20 V-Loc suture then follows in a continuous horizontal mattress fashion to reapproximate the renal parenchyma and complete the renorrhaphy. Alternatively, the outer renorrhaphy can be completed with a continuous running baseball stitch and a sliding Hem-o-loc clip after each wall-to-wall throw (Fig. 2D). Bulldog clamps can be removed after base suturing is completed to
Fig. 1. Arterial clamping and tumor resection.
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Fig. 2. Steps of renorrhaphy.
minimize warm ischemia. Following renorrhaphy, insufflation pressure is reduced to 5 mm Hg for 5e10 min to evaluate for surgical bleeding. Once hemostasis is ensured, the specimen is extracted after enlarging the camera port or working port incisions. A separate Pfannenstiel, Gibson, or lower midline incision can be made if the specimen is substantially large. The extraction site is determined by each surgeon's preference. A surgical drain is usually placed in the paracolic gutter adjacent to the kidney when the collecting system is entered during mass excision, although some authors contend that can be safely omitted given the low rates of urine leaks [14]. The 10- and 12-mm trocar sites are closed under direct laparoscopic vision. Pneumoperitoneum is released and all incision are closed at the skin level with subcuticular sutures and covered with bonding agent or adhesive strips. 6.1. Off-clamp (zero-ischemia) technique Off-clamp or “zero ischemia” approach to partial nephrectomy (PN) has been gaining popularity over the past several years and has been established to offer comparable perioperative safety, equivalent oncologic outcomes, and superior long-term renal function preservation when compared with on-clamp approach for RCC in appropriately selected patients [15]. Specifically for LPN, the technique avoids renal ischemic injury with the benefits of minimally invasive surgery for peripheral cT1-T2 tumors [16]. Traditionally, clamping the renal hilum during LPN allows for minimal blood loss and better visualization during dissection and renorrhaphy. However, renal ischemia and reperfusion injury is a consequence of hilar occlusion. As anticipated, using an off-clamp
technique during LPN has variably shown increased EBL when compared to hilar-controlled operations but this does not seem to translate into increased risk of transfusion or loss of visualization leading to compromise in oncologic outcomes [17].
6.2. Selective arterial clamping Gill et al. first described the technique of anatomic vascular microdissection (VMD) of renal artery branches to allow selective clamping of vessels to extend the application of zero-ischemia PN [18]. This allowed more complex tumors such as hilar, central, intrarenal, and polar lesions to be resected without global surgical renal ischemia. After exposure of the renal hilum, the main renal artery and vein are circumferentially mobilized and encircled with vessel loops. After assessing the patient's preoperative CTreconstructed 3-dimensional hilar architecture, microdissection is performed in a medial-to-lateral direction to identify the specific arterial branches supplying the tumor. Microsurgical bulldog clamps are used to clamp the targeted arterial branches and evaluation of the collateral kidney around the tumor is performed to confirm normal color and turgor. If there is concern the branch clamped has decreased perfusion to normal kidney, the bulldog is unclamped immediately. Arterial mapping with this superselective ligation approach is done until only branches to the tumor(s) are clamped and the rest of the kidney is free from ischemia. The use of a laparoscopic Doppler can also help with identification of target arterial branches; cessation of intratumor and peritumor arterial flow confirms that the correct arterial branch has been controlled.
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7. Retroperitoneal approach
10. Oncologic outcomes
A retroperitoneal approach to laparoscopic partial nephrectomy is most beneficial for posteriorly located masses and in instances where considerable intraperitoneal adhesions are anticipated. Because of the limited working space and fewer familiar landmarks, the retroperitoneal approach can prove challenging in particularly obese patients with considerable retroperitoneal adiposity, and in patients with perirenal scar tissue from prior renal surgery or infections.
The trifecta of negative cancer margins, preserved renal function, and minimal perioperative complications e goals that are essential for open partial nephrectomy (OPN) e have been welltranslated to LPN across the urologic literature [20e22]. Positive surgical margins for most LPN series remain less than 1% with cancer-specific survival (CSS) of over 95% and 90% at ten years for cT1a and cT1b RCC, respectively [23]. The role and indications of LPN have been expanded to much more complex tumors e hilar, completely endophytic, and T1b and larger e and technical modifications have improved WIT and overall renal function preservation. LPN remains a valid alternative to OPN and a viable modality despite rapid technological advancements in robotics and ablative therapies.
8. Postoperative management Most institutions recommend 12e24 h of bed rest with patients ambulating by the morning of postoperative day one [17]. Some authors will recommend even earlier ambulation in order to prevent deep vein thrombosis. Both prophylactic doses of subcutaneous heparin as well as compression stockings should be applied immediately postoperatively. In patients at particularly high risk for DVT, preoperative prophylactic dosing of subcutaneous heparin or enoxaparin should be considered. In general, any oro- or nasogastric tube is removed prior to extubation and the patient is given a clear liquid diet in the recovery room once fully awakened from anesthesia. The diet is continued or advanced the next morning depending on clinical indications. The Foley catheter is kept overnight to measure outputs and removed the next morning. Drain output volumes are meticulously monitored after Foley removal because any significant increase may represent vesicoureteral reflux into a persistent or unrecognized collecting system injury. The creatinine concentration of the drain fluid is analyzed and compared to the serum creatinine level to assess for urine leak and to help determine the timing of drain removal. The Foley catheter may be reinserted if output from surgical drain is suggestive of urine leak and if volumes are significant. Most patient are discharged home postoperative day one or two without any external tubes. Patients are provided with a bowel regimen and narcotic pain medication to take as needed. For pT1 tumors, LPN patients are followed with abdominal imaging (CT or MRI) within three to twelve month postoperatively, in addition to chest X-ray and laboratory studies, as per AUA surveillance guidelines.
9. Surgical complications Intraoperative complications usually are associated with inadequate vascular control such as clamp failure, inability to identify and control multiple renal arteries, or poor haemostatic control during base-layer suturing and renorrhaphy. In larger studies, intraoperative hemorrhage can range as high as 3.5% and require conversion to open in 1% [19]. Additional less common injuries can occur to the ureter, bowel, spleen, liver and gallbladder, pancreas, and great vessels. Postoperative complications are typically related to bleeding or urine leak. Delayed spontaneous hemorrhage can occur up to 30 days postoperatively and has a reported frequency as high as 9.5%. The incidence of urine leak is approximately 4.5% [19]. Conservative management, selective angioembolization, or completion nephrectomy are the treatment options depending on clinical severity. Collecting system injuries rarely require reoperation with most resolving spontaneously and less than 10% needing urinary diversion (by either ureteral stent or percutaneous nephrostomy) [19].
Conflicts of interest None. Sources of funding None. Ethical approval N/A. Author contribution All authors contributed equally to study design and writing. This is a review paper, thus no data collection or analysis. Guarantor Philip Zhao, MD. References [1] B.R. Lane, S.C. Campbell, I.S. Gill, 10-year oncologic outcomes after laparoscopic and open partial nephrectomy, J. Urol. 190 (1) (2013) 44e49. [2] R.L. Favaretto, R. Sanchez-Salas, N. Benoist, et al., Oncologic outcomes after laparoscopic partial nephrectomy: mid-term results, J. Endourol. 27 (1) (2013) 52e57. [3] M. Marszalek, H. Meixl, M. Polajnar, et al., Laparoscopic and open partial nephrectomy: a matched-pair comparison of 200 patients, Eur. Urol. 55 (5) (2009) 1171e1178. [4] M.N. Simmons, C.J. Weight, I.S. Gill, Laparoscopic radical versus partial nephrectomy for tumors >4 cm: intermediate-term oncologic and functional outcomes, Urology 73 (5) (2009) 1077e1082. [5] H.S. Al-Qudah, A.R. Rodriguez, W.J. Sexton, Laparoscopic management of kidney cancer: updated review, Cancer Control 14 (3) (2007) 218e230. [6] T. Klatte, S.F. Shariat, M. Remzi, Systematic review and meta-analysis of perioperative and oncologic outcomes of laparoscopic cryoablation versus laparoscopic partial nephrectomy for the treatment of small renal tumors, J. Urol. 191 (5) (2014) 1209e1217. [7] E. Hyams, P. Pierorazio, J.K. Mullins, et al., A comparative cost analysis of robot-assisted versus traditional laparoscopic partial nephrectomy, J. Endourol. 26 (7) (2012) 843e847. [8] J.S. Ellison, J.S. Montgomery, J.S. Wolf Jr., et al., A matched comparison of perioperative outcomes of a single laparoscopic surgeon versus a multisurgeon robot-assisted cohort for partial nephrectomy, J. Urol. 188 (1) (2012) 45e50. [9] A.S. Go, G.M. Chertow, D. Fan, Chronic kidney disease and the risks of death, cardiovascular events, and hospitalization, N. Engl. J. Med. 351 (13) (2004) 1296e1305. [10] M. Daugherty, G. Bratslavsky, Compared with radical nephrectomy, nephronsparing surgery offers a long-term survival advantage in patients between the ages of 20 and 44 years with renal cell carcinomas (4 cm): an analysis of the SEER database, Urol. Oncol. 32 (5) (2014) 549e554. [11] B. Xu, Y. Mi, L.Q. Zhou, et al., Laparoscopic partial nephrectomy for multilocular cystic renal cell carcinoma: a potential gold standard treatment with excellent perioperative outcomes, World J. Surg. Oncol. 23 (12) (2014) 111.
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[12] R. Abaza, Robotic surgery and minimally invasive management of renal tumors with vena caval extension, Curr. Opin. Urol. 21 (2) (2011) 104e109. [13] Y. Funahashi, M. Kato, Y. Yoshino, et al., Comparison of renal ischemic damage during laparoscopic partial nephrectomy with artery-vein and artery-only clamping, J. Endourol. 28 (3) (2014) 306e311. [14] R. Abaza, D. Prall, Drain placement can be safely omitted after the majority of robotic partial nephrectomies, J. Urol. 189 (3) (2013) 823e827. [15] W. Liu, Y. Li, M. Chen, et al., Off-clamp versus complete hilar control partial nephrectomy for renal cell carcinoma: a systematic review and meta-analysis, J. Endourol. 28 (5) (2014) 567e576. [16] S. Rais-Bahrami, A.K. George, A.S. Herati, et al., Off-clamp versus complete hilar control laparoscopic partial nephrectomy: comparison by clinical stage, BJU Int. 109 (9) (2012) 1376e1381. [17] J.E. Kreshover, L.R. Kavoussi, L. Richstone, Hilar clamping versus off-clamp laparoscopic partial nephrectomy for T1b tumors, Curr. Opin. Urol. 23 (5) (2013) 399e402.
[18] C.K. Ng, I.S. Gill, M.B. Patil, et al., Anatomic renal artery branch microdissection to facilitate zero-ischemia partial nephrectomy, Eur. Urol. 61 (1) (2012) 67e74. [19] A.P. Ramani, M.M. Desai, A.P. Steinberg, et al., Complications of laparoscopic partial nephrectomy in 200 cases, J. Urol. 173 (1) (2005) 42e47. [20] A.J. Hung, J. Cai, M.N. Simmons, et al., “Trifecta” in partial nephrectomy, J. Urol. 189 (1) (2013) 36e42. [21] H. Zargar, M. Allaf, S. Bhayani, et al., Trifecta and optimal peri-operative outcomes of robotic and laparoscopic partial nephrectomy in surgical treatment of small renal masses: a multi-institutional study, BJU Int. 116 (3) (2015) 407e414. [22] A. Khalifeh, R. Autorino, S.P. Hillyer, et al., Comparative outcomes and assessment of trifecta in 500 robotic and laparoscopic partial nephrectomy cases: a single surgeon experience, J. Urol. 189 (4) (2013) 1236e1242. [23] B.R. Lane, S.C. Campbell, I.S. Gill, 10-year oncologic outcomes after laparoscopic and open partial nephrectomy, J. Urol. 190 (1) (2013) 44e49.
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