Initial Experience of Umbilical LaparoendoscopicSingle-Site Nephron-Sparing Surgerywith KeyPort and DuoRotate System

Pedro M. Cabrera, MD, Felipe Caceres, MD, Ana Garcıa-Tello, MD, and Javier C. Angulo, MD, PhD

Abstract

Objectives: To present the feasibility of laparoendoscopic single-site (LESS) nephron-sparing surgery (NSS)using new reusable umbilical single-port system and instruments.Methods: A prospective study was performed to evaluate operative data and patient outcomes after LESS-NSSwith KeyPort�, a tri-channel single-port placed through a 2.5-cm umbilical incision, and specific DuoRotate�

instruments. Patient characteristics, operative time, estimated blood loss (EBL), complications, visual analog painscale (VAPS), and visual analogue wound satisfaction scale (VAWSS) scores were registered.Results: Six consecutive nonselected patients with indication of NSS and normal contralateral kidney wereoffered LESS-NSS. An accessory 3.5 mm port that facilitated renoraphy and unclamped technique was used in 4(66.7%) cases each. Median tumor maximum size was 4.0 (1–7.5) cm; age 64 (31–76) years; body mass index 28.4(22.1–39.3) kg/m2; operative time 233.5 (140–250) min; EBL 500 (200–500) mL; difference in hemoglobin 2.3 (0.1–4.6) g/dL. VAPS at day 2 was 0.7/10 and the median length of stay 3 (2–4) days. One case (16.7%) neededtransfusion. None required conversion to standard laparoscopy or use of other additional ports. Postoperativecomplications occurred in 3 (50%) and major complications in 1 (16.7%). Incisions were totally hidden in theumbilicus. Pathology revealed angiomyolipoma (3), renal cell carcinoma (2), and chronic inflammation (1).Tumor margins were negative in all cases with malignancy. VAWSS at first month was 9.4 (8.1–10). At a medianfollow-up of 24 (10–32) weeks, no patient developed complications related to the approach.Conclusions: Umbilical LESS-NSS through a new single-port system of reusable nature, with or without the helpof an accessory port and occasionally without clamping, can be effectively and very economically performedwith minimum postoperative pain. Good candidates are patients with presumed benign renal masses thatappreciate the cosmetic advantage of the approach.

Introduction

Nephron-sparing surgery (NSS) has gained popularityto treat small renal masses, even to the extent that it is

claimed to improve renal function and life expectancy com-pared to radical nephrectomy, due to the fact that nephronmass reduction implies accelerated renal damage.1 In thissense, not only kidney removal, but also hilum clamping canbe avoided or shortened to improve results of renal cell sur-gery. The notorious rise of incidental detection of renal mas-ses2 and the experience acquired in recent years withlaparoscopic and robotic NSS have allowed the excellent re-sults of minimally invasive NSS, both from the oncologicaland functional perspective, even in complex cases.3

The kidney has become the organ of preference to investi-gate the advances of minimally invasive surgery and, partic-

ularly, laparoendoscopic single-site surgery (LESS),4 which isthe latest evolution of laparoscopy. LESS avoids multiplescars and diminishes port-related morbidity, thus minimizingpatient discomfort and maximizing the cosmetic benefit of asmall incision.5,6 Therefore, it is not striking that LESS-NSS isbeing increasingly performed in recent years worldwide7 andstands for 6%–34.5% of the procedures reported in large LESSseries from individual institutions or collaborative groups,both laparoscopic and robotic.7–10

Despite the difficulty, laparoendoscopic single-site un-clamped NSS has also been reported in highly selectedpatients with favorable tumor anatomic features and use ofthe harmonic scalpel or ligasure tissue sealing system.11–13 Wedescribe our initial clinical experience with LESS partial ne-phrectomy using a novel umbilical single-port access deviceand Duo-rotate prebent instruments of reusable nature that

Department of Urology, Foundation for Biomedical Research, University Hospital of Getafe, European University of Madrid, Madrid,Spain.

JOURNAL OF ENDOUROLOGYVolume 27, Number 5, May 2013ª Mary Ann Liebert, Inc.Pp. 566–572DOI: 10.1089/end.2012.0572

566

diminish the need of additional trocars and also allow per-formance of unclamped surgery. Technique, results, andcomplications are described and data regarding historicalcontrol with laparoscopic partial nephrectomy (LPN) in ourinstitution are provided for indirect comparison.

Materials and Methods

The KeyPort (Richard Wolf) was first experimented both inphantoms and in the porcine model following the regulationsof the Autonomic Community of Madrid for animal care.Once 200 hours of training were individually achieved by twoexperienced surgeons with more than 300 previous laparo-scopic procedures (PMC & FC), several low-risk human LESSsurgeries (cryptorchidism, pyelolithectomy, and pyeloplasty)were performed before more complex retroperitoneal andpelvic surgeries were accomplished. Prospective data collec-tion on the initial experience with this new system at ouracademic institution was stored since October 2011 to June2012 in a patient-identified database in accordance with theinstitutional review board approval. The first NSS was per-formed with this system in January 2012.

The patient was placed in the 45–60� modified flank posi-tion with the operating table minimally flexed. A reusablerigid trocar that fits a 2.5-cm umbilical opening without needof external or internal fixation was inserted in a screw-drivenfashion (Fig. 1). The inner element was removed and the softmultichannel cover with three openings (5, 10, and 15 mm,respectively), was closed to insert curved instruments com-posed of inner sheath, outer element, and handle. Both Key-Port and inserts were entirely reusable. These elementsincorporated a new Duo-rotate� system (Richard Wolf) al-lowing precise 360� movement of the tips after alignment ofthe arms. A 5.3 mm wide, 45 cm long, 30� lens laparoscopeand two operative curved instruments were used (mainlyatraumatic prehension forceps and Metzenbaum scissors) inturns with a long suction reusable irrigation system and bi-polar electrocautery (Richard Wolf), Force-triad (Covidien) (5or 10 mm if desired) and Endopouch Retriever ( Johnson &Johnson). Right-handed surgeons used the forceps grasperwith the left hand (right side of the screen) and the scissors orForce-triad with the right hand (appears on the left) (Fig. 2).

Whenever a renal suture was planned, a 3.5-mm additionalport was placed in the flank, or iliac fossa for lower pole

FIG. 1. Reusable rigidtrocar inserted in theumbilicus (A). Inner elementis removed and the softmultichannel cover closed (B)before the insertion of theinstruments.

FIG. 2. External (A) andlaparoendoscopic (B) view ofleft side nephron-sparingsurgery with KeyPort and 3.5accessory trocar. The mainsurgeon uses the duo-rotateinstrument (left hand) andapplies Force-triad (righthand).

UMBILICAL LESS NEPHRON-SPARING SURGERY 567

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tumors. Hepatic retraction was in a case facilitated with directinsertion of a needlescopic instrument. All the cases in theseseries were performed with one (or none) accessory port(Table 1). This access was used for suturing with a needleholder and also to extract the drainage far from the umbilicusto prevent hematoma formation or infection and also facili-tated proper working angle and avoided clashing of the lap-aroscope with the instruments. The technique we describe canbe interpreted as a hybrid LESS procedure (one or two porttechnique) with minimum accessory trocar dependence. Themain surgeon used Duo-rotate instruments and appliedForce-triad, Hem-o-lok or bulldog clamp with the right hand.The assistant held the camera and used the accessory port, ifneeded, to retract or aspirate.

The renal pedicle was prepared carefully in every case,even when unclamped. The lower pole was lifted by gentletraction to prepare the vessels. The renal vein and artery wereidentified and dissected. The tumor was localized and ex-posed. The renal artery first, and then the renal vein wereclamped with separate bulldog clamps (Fig. 3). Excisionunder normal renal perfusion was performed in cases withfavorable peripheral location, external growth, and presumedeasy cleavage plane. The tumor size was not considered cru-cial to decide performing the unclamp technique.

After excision of the neoplasm, parenchymal hemostasiswas achieved by bipolar electrocautery, parenchymal stitchesusing a 0 polidiosanone violet monofilament synthetic ab-sorbable bidirectional cut-in-two barbed suture Quill (An-giotech) tensioned by Hem-o-lok, and autologous fibrinsealant prepared with the Vivostat system and applied to theresection bed. The specimen was placed in an endoscopic bagand when used, the drain was extracted through the accessoryport. Finally, KeyPort removal was followed by extraction ofthe pocketed specimen through the umbilicus.

Preoperative laboratory values 2 weeks before surgery andpostoperative data on day 2 were registered. Renal functionaloutcomes as revealed by creatinine and eGFR were investi-gated at mo 1. The tumor size was assessed based on com-puterized tomography. Estimated blood loss, operative time,conversion to standard laparoscopy, intraoperative andpostoperative complications, following Clavien-Dindo clas-sification, hospital stay, and visual analog pain scale (VAPS)at day 2 from 0 to 10, were registered. Patient satisfaction in avisual analogue wound satisfaction scale (VAWSS) at 3–4weeks from 0 to 10 was also investigated. This scale is pro-vided by showing the patient the sketches of three differentincisions (open incision in the form of lumbothomy, laparo-

scopy with five ports, and LESS with umbilical incision andone additional port) through which surgery could have beenperformed and immediately after asking him/her to definethe scale he/she would give to his/her own incision in termsof satisfaction with the wound.14 Patients were also specifi-cally followed for evidence of local umbilical adverse eventsand for the cosmetic aspect of the wound, and patients withrenal cell cancer were scheduled for long-term follow-up.

Results

Six patients (two male and four female) underwent trans-peritoneal LESS partial nephrectomy with KeyPort and Duo-rotate instruments (Table 1). The indication was solitary renalmass in 5 (3 of which were suspiciously malignant) and du-plicated ectopic ureter with upper pole renal atrophy andrecurrent urinary infection in another case. Patient charac-teristics were median age 64 years (range 31–76) and bodymass index (BMI) 28.4 (22.1–39.3) kg/m2. Previous abdominalsurgery had been performed in 50% of the cases. During thesame time span, eight patients with RCC were intervenedwith umbilical LESS radical nephrectomy and four patientswith urothelial malignancy and renal involvement receivedumbilical radical nephroureterectomy. Historical series ofpatients treated with LPN in our institution has already beenpresented.15

Outcomes and complications

Unclamped KeyPort NSS was performed in 4 of 6 cases(66.7%) and warm ischemia time (WIT) in the remaining 2 was27 and 28 minutes, respectively. Pathologic analysis revealedangiomyolipoma in 3 (preoperatively suspected in 2 of themfor the presence of an adipose component), renal cell carci-noma (RCC) in 2 (chromophobe RCC and papillary RCC,respectively), and chronic inflammation in a case. The mediantumor maximum size was 4 (1–7.5) cm. The largest lesionsintervened were those with preoperative suspicion of angio-myolipoma (6.3 and 7.5 cm) (Fig. 4). Clamped NSS was per-formed in a RCC with R.E.N.A.L. nephrometry score 8 and ina epithelioid angiomyiolipoma (PEComa) with R.E.N.A.L.score 5 and profuse intraoperative bleeding (Table 1). Tumormargins in the patients with RCC and PEComa were negative.

The ureteral catheter was placed intraoperatively foropening of the collecting system in two cases. Operative timewas 233.5 (140–250) min, estimated blood loss 500 (200–500)mL, and difference of hemoglobin 2.25 (0.1–4.6) g/dL at day 2.Median length of hospital stay was 3 (2–4) days. VAPS at day

FIG. 3. Renal vein and artery are carefully dissected, even in unclamped technique (A). When clamped, two bulldogs areplaced separately on artery and vein (B). Autologous fibrin sealant (Vivostat system) applied to the resection bed to completehemostasis (C).

UMBILICAL LESS NEPHRON-SPARING SURGERY 569

2 was 0.7 (0–2.7) of 10. Median creatinine and eGFR at mo 1were 0.74 (0.49–1.02) mg/dL and 87.7 (71–110) mL/minute,respectively.

Postoperative complications presented in 50% of the casesand included 1-day stay in the intensive care unit due to dif-ficulties for extubation (IVa), pulmonary embolism diagnosed15 days after discharge requiring readmission (IId), and cecaldilatation (I). The last one was clinically insignificant. Pre-ventive measurements (heparin, graduated compressionstockings, pneumatic compression, and early mobilization)had been used in the 31-year-old female patient who devel-oped pulmonary embolism, readmitted for increased tem-perature 2 weeks after hospital discharge. She recoveredwithout sequel.

Transfusion was needed intraoperatively in 1 case (16.7%)due to severe hemorrhage (Table 1). No patient requiredconversion to standard laparoscopy or open surgery. Theprocedure was performed without additional ports in twocases (33.3%), only one additional 3.5-mm trocar was used in 4(66.7%), and no case required 2 or more extra ports. Incisionwas always hidden in the umbilicus, and in some patients, thescar produced by the additional port was also invisible (Fig.5). VAWSS within the first month was 9.4 (8.1–10). Medianfollow-up was 24 (10–32) weeks. No patient developed um-bilical hernia or late complications related to the approach. Inone case, umbilical hernia was present before surgery and wassimultaneously corrected.

Discussion

Since the original description of LESS to perform nephrec-tomy through the umbilicus,16 this procedure has evolved to

be safely and efficiently practiced by an increasing number ofgroups. Partial nephrectomy or NSS is a very interesting LESSurological surgery,5,6 but still remains one of the most chal-lenging procedures to be performed through a single port withsomewhat more than a hundred cases reported worldwide,consistently renal tumors of mean size between 2.1 and3.2 cm.6,8,10–13,17,18 Discussion whether LESS-NSS can be gen-eralized is beyond our scope, but studying the feasibility ofthis technique with the new instruments may be a step todiminish the technical limitations of existing instrumentation.8

Robotic LESS-NSS was initially described with the scopeand a 5-mm trocar placed through a multichannel port (Tri-port, Advanced Surgical Concepts) and a second 5-mm trocarthrough the same skin incision alongside.11 A large series ofrobotic LESS-NSS has been recently described in Korea with ahomemade single-port device established by inserting two 12-mm trocars and two 8-mm trocars through the fingers of asurgical glove.6,10 Possibly, future more precise manual sys-tems will contribute to further improve this new field ofsurgery at a more reasonable cost.

The reusable KeyPort system that incorporates prebentinstruments with double rotation is one of these recent de-velopments to be placed preferentially inside the umbilicus.This surgery implies high patient satisfaction because thescar is easily concealed within the navel and appears feasibleboth for radical prostatectomy, cystoprostatectomy, and anumber of reconstructive procedures.14,19–21 We describeour initial experience with KeyPort NSS, with special em-phasis on the viability of the unclamp modality. A partialnephrectomy can be considered one of the ideal surgeries topromote a pure umbilical approach, because the size andconsistence of the specimen makes the extraction through

FIG. 4. Computerizedtomography scan of patientswith renal cell carcinoma (A)and angiomyolipoma (B),corresponding to cases 4 and5 of the series.

FIG. 5. Postoperativeaspect: invisible umbilicaland subxyphoid scars (A) incase 4 and inconspicuousumbilical keloid (B) in case 1.

570 CABRERA ET AL.

the navel an excellent alternative with cosmetic benefit andprompt repair.6,9,18 Of course, limitations of the techniqueare the teaching curve and also the limited access from anumbilical approach for large renal masses in the upper poleand the adrenal field.

It is obvious that concentrating the incisions on a uniquesite characteristic of LESS implies a diminished motion rangeand impairs visualization. Nevertheless, the KeyPort incor-porates a conceptual change as individual instruments havemoved to a combined dual system of arms that avoids bothexternal clushing and internal crossing by a combination ofthe curved nature of the instruments and the articulated ro-tation of their duo-rotate tip allowing precise movementswithout rigidity loss. Besides, the reusable nature of both in-struments and port makes this alternative especially attrac-tive. Also, the additional use of needlescopic material can bevery beneficial without any cosmetics impact and facilitatesthe most critical steps of the procedure.22

Certainly, cosmesis is not the top priority when performinga complex surgical procedure like a partial nephrectomy.Other possible benefits of LESS for major surgery under studyare diminished postoperative pain, decreased analgesic use,shortened convalescence, and performance of a more carefulsurgery that could imply less estimated blood loss and alsodecreased hospital stay.5,23 Besides, from an economical per-spective, it should be stressed that a reusable port accesssystem and materials are clearly advantageous.14,24 Of course,this early experience should be consolidated in the future bymore robust studies.

A comparison with conventional LPN or robotic-assistedLPN is impossible because of the absence of prospectiverandomized studies.25 Also, the series we present was notmatched with a control group. However, historical data in ourinstitution revealed 107.2 (50–185) minutes mean surgicaltime, 26.8 (18–40) mean BMI, and 3.1 (1.2–7)-cm mean tumorsize. Besides, hilum clamping was almost routinely per-formed, with a WIT of 33 (0–70) minutes. The urinary tractwas repaired in 53% of the cases. Intraoperative bleeding re-quiring transfusion occurred in 8.7%, and the transfusion rateduring admission was 20%. Postoperative complicationspresented in 18.7% and 6.7% were Clavien III. No case wasconverted to open nephrectomy. Mean postoperative staywas 5 (3–29 days). The proportion of cases with benign his-tology was 16.6%. Local recurrence developed in 1.7% at 31mo mean follow-up.15

The umbilical approach allowed performance of the un-clamped technique with an invisible scar in selected caseswith longer operating time and shorter hospital stay.15 Whenclamping was performed, WIT was not longer that in histor-ical data. Transfusion rate was similar, but the complicationrate appeared higher in LESS-NSS, although this may be due,in part, to good reporting of complications and also to thesmall numbers reported.

According to the standardized R.E.N.A.L. score system,26

none of the consecutive cases we have intervened were ofhigher complexity. However, the mean tumor size in this se-ries is higher than previous reports in the literature6,8,10–13,17,18

and morbidity associated to NSS is related to the size of thelesion.27 Besides, if other preliminary series are studied indetail, significant complications can also be appreciated, in-cluding bleeding requiring transfusion6,8,11 and sometimesconversion to laparoscopy8,11,12 or open mini-incision,6,10

pseudoaneurism requiring selective angioembolization,17 ce-rebrovascular accident with hemiparesis,12 pulmonary em-bolism17 and bowel, ureter or renal vein injuries.10 Thereported transfusion rate is very variable and ranges between0 and 78.6%.6,8,11–13,17,18

Whether umbilical LESS approach is advantageous toperform NSS in a patient with solitary renal mass compared toconventional laparoscopy remains to be proven. However, weconfirm umbilical LESS partial nephrectomy using the Key-Port is feasible in a wide variety of clinical settings. It can beperformed with very low postoperative pain, excellent satis-faction with the wound, no-clamping or nonprolonged reg-ular WIT, and short hospital stay. Although it is not alwayspossible to determine whether a solid renal mass is benign ornot based on imaging studies, best candidates are in ouropinion patients with benign renal masses needing surgerythat appreciate the cosmetic advantage of the approach, es-pecially large angiomyolipoma with good cleavage plane.This preliminary study does not allow reliable oncologic as-sessment, but appropriate tumor margins were achieved inpatients with RCC and PEComa. As can be expected for anoncologic procedure of high complexity, umbilical LESSpartial nephrectomy is not devoid of operative and post-operative complications that resemble those of laparoscopy20

and are therefore linked more to the procedure than theapproach.28,29

Conclusion

Umbilical LPN through a single port developed by RichardWolf (KeyPort) to be used with a 5.3 mm wide, 45 cm long, 30�lens laparoscope and two operative working curved instru-ments that incorporate a new system that allows precise 360�movement of the tips after alignment of the arms (Duo-rotate).Satisfactory operative parameters can be achieved, also withexcellent cosmetic results and postoperative analgesia. In se-lected cases, the procedure can also be performed withoutclamping. The entire reusable nature of this device implies avery important economical advantage. This favorable earlyexperience with the new device should be consolidated bymore robust studies in the future.

Acknowledgments

The authors thank Mr. Jesus Arconada (Grupo Taper,Madrid), Mr. Stefan Gille, Mr. Benjamin Seidenspinner, andMr. Juergen Steinbeck (Richard Wolf GMBH, Knittlingen) forproviding constant instrumental support and Mr. Jose Dom-ınguez for photographic assistance.

Disclosure Statement

Authors (PMC, FC, AG, and JCA) have no commercialassociations that might create a conflict of interest in connec-tion with the submitted manuscript. JCA has received grantsfrom Astellas and Pfizer and has given lectures for Astellas,Pfizer, and GSK. PMC, FC, and AG have nothing to disclose.

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Address correspondence to:Javier C. Angulo, MD, PhD

Hospital Universitario de GetafeCarretera de Toledo Km 12,500

28905 MadridSpain

E-mail: jangulo@futurnet.es

Abbreviations UsedBMI¼ body mass index

CT¼ computerized tomographyEBL¼ estimated blood loss

LESS¼ laparoendoscopic single siteLPN¼ laparoscopic partial nephrectomyNSS¼nephron-sparing surgeryRCC¼ renal cell carcinoma

VAPS¼visual analog pain scaleVAWSS¼visual analogue wound satisfaction scale

WIT¼warm ischemia time

572 CABRERA ET AL.