Comparison of transurethral enucleation with bipolar and transurethral resection in saline for managing benign prostatic hyperplasia

Authors


Yosuke Hirasawa, Department of Urology, Saitama Municipal Hospital, 2460 Mimuro, Midori-ku, Saitama 336-8522, Japan. e-mail: wbqmd473@yahoo.co.jp

Abstract

Study Type – Therapy (case series)

Level of Evidence 4

What's known on the subject? and What does the study add?

Transurethral enucleation with bipolar (TUEB) has been widely adopted as an alternative to standard TURP, although the surgical technique, efficacy and safety of TUEB have not been described so far.

The present study provides illustrations of the TUEB technique, as well as peri-operative, 6-month and 12-month follow-up results of TUEB from a retrospective review of a single-institution experience comparing the efficacy and safety of TUEB and transurethral resection in saline for managing BPH.

OBJECTIVE

  • • To illustrate the transurethral enucleation with bipolar (TUEB) technique and compare the efficacy and safety of TUEB and transurethral resection in saline (TURis) for managing benign prostatic hyperplasia (BPH).

PATIENTS AND METHODS

  • • A retrospective review of a single-institution experience of 110 consecutive TUEB or TURis between 2008 and 2011 at our hospital was performed aiming to compare the efficacy and safety of TUEB and TURis for managing BPH (55 patients in each group).
  • • Peri-operative data included operating time, resected tissue weight, changes in haemoglobin, duration of catheterization, hospital stay and early complications.
  • • Postoperative outcomes included 6- and 12-month postoperative International Prostate Symptom Score (IPSS), and Quality of Life (QoL) score, uroflowmetry findings, change in serum prostate-specific antigen level and all late complications in the two groups.

RESULTS

  • • Both groups were well matched for age, preoperative prostate volume, IPSS, QoL and uroflowmetry findings.
  • • The change in haemoglobin at postoperative day 1 in the TUEB group was significantly less than in the TURis group (1.08 vs 1.60 g/dL; P < 0.001).
  • • Catheterization time and hospital stay were significantly shorter in the TUEB group than in the TURis group and the mean retrieved tissue weight in the TUEB group was larger than that in the TURis group (41.3 vs 31.7 g; P= 0.007).
  • • Patients in the two arms had comparable improvements in postoperative IPSS, QoL, maximum flow rate and postvoid residual urine volume.
  • • The rates of complications were equally low with each procedure.

CONCLUSION

  • • TUEB is superior to TURis, with less bleeding, as well as decreased catheter time and hospital stay, although showing equivalent efficacy at 12 months of follow-up.
Abbreviations
HoLEP

holmium-laser enucleation of the prostate

PVR

postvoid residual urinary volume

QoL

Quality of Life

TUEB

transurethral enucleation with bipolar

TUR

transurethral resection

TURis

transurethral resection in saline

INTRODUCTION

TURP has been the standard surgical treatment for BOO secondary to BPH and is considered to be safe and effective [1]. However, various problems have been found with this treatment, such as postoperative bleeding and irrigant absorption, leading to transurethral resection (TUR) syndrome [2,3]. In particular, complications causing haemorrhage lead to delayed hospital discharge and possible blood transfusion [4]. For this reason, many alternative energy modalities have been developed in an attempt not only to provide an effective surgical treatment for BPH, but also to minimize the risk of complications and the length of hospital stay.

Such technological advances include the transurethral resection in saline (TURis) system and holmium-laser enucleation of the prostate (HoLEP). The former has enabled elimination of TUR syndrome [5] and the latter, which involves enucleation of the whole prostate by dissecting between the surgical capsule and the adenoma with a holmium laser, has enabled reduction of adverse events such as bleeding and TUR syndrome, at the same time as maintaining therapeutic efficacy [6]. The use of bipolar electrosurgical technology has shown fewer complications and comparable results to standard TURP in early and short follow-ups [7].

More recently, transurethral enucleation with bipolar (TUEB), which is a treatment involving blunt adenoma enucleation with a spatula attached to the standard tungsten wire loop in addition to the TURis system, has been established. In the TUEB approach, urologists do not need to purchase a laser system when they perform TUEB. Therefore, TUEB has made adenoma enucleation possible for urologists in hospitals that have no laser system. However, the surgical technique, efficacy and safety of TUEB have not been described so far. Furthermore, there have been no reports comparing TUEB and TURis. The present study is the first to illustrate the TUEB technique and compare the efficacy and safety of TUEB and TURis for managing BPH.

PATIENTS AND METHODS

PARTICIPANTS

We identified and retrospectively reviewed 110 patients with BPH who were treated by TUEB or TURis at our institution between 2008 and 2011. Of these 110 patients, 55 (50.0%) were treated by TUEB and 55 (50.0%) by TURis. All patients provided a detailed history and underwent a physical examination that included a DRE, and serum PSA level was evaluated. Patients with palpable nodules on the DRE or with PSA levels > 3 ng/mL before surgery underwent prostate tissue biopsy to assess for prostate cancer. Voiding symptoms and quality of life (QoL) were graded according to the IPSS and its QoL assessment index. Symptoms were estimated using the IPSS, and uroflowmetry was used to obtain the maximum urinary flow rate (Qmax) and mean urinary flow rate (Qmean). Prostate size and postvoid residual urinary volume (PVR) were measured by transrectal and transabdominal ultrasonography, respectively. Any patient with a previous history of prostatic or urethral surgery, neurovesical dysfunction and/or carcinoma of the prostate was excluded. Indications for surgery were an IPSS ≥ 12 points before surgery and a maximal urinary flow rate (Qmax) <15 mL/s. During surgery, the outcomes measured in the two groups included operating time, resected tissue weight, changes in haemoglobin, duration of catheterization, hospital stay and early complications. In all patients in the two groups, the catheter was subsequently removed when the urine was a light rose colour or clear. Patients were discharged home the day after the catheter was removed. Blood transfusion was initiated when serum haemoglobin was <8 g/dL or symptoms of acute blood loss were apparent. All patients also underwent uroflowmetry assessment at the 6- and 12-month follow-ups with measurement of Qmax, Qmean and PVR. Preoperative, 6- and 12-month postoperative IPSS, QoL scores, Qmax, Qmean, PVR, change in serum PSA level and all late complications were evaluated. Stress incontinence was defined as any patient wearing at least one pad for protection against urinary leakage during stress manoeuvers.

All statistical analyses comparing the two procedures were performed using Student's t-test. P < 0.05 was considered statistically significant. These analyses were carried out using SPSS, version 11.0 (SPSS Inc., Chicago, IL, USA).

INTERVENTIONS

TUEB involved enucleation of the prostate using the Olympus SurgMaster (Olympus Europa Holding GmbH, Hamburg, Germany) TURis system and the TUEB loop, which is characterized by a spatula attached to the standard tungsten wire loop (Fig. 1). After cystoscopy, resection was made at the 12 o'clock position, then at the 6 o'clock position to enucleate the lateral lobes in the case of bilobular hypertrophy (Fig. 2a). In the case of trilobular hypertrophy, resection was made at the 12 o'clock position, then at the 5 and 7 o'clock positions.

Figure 1.

The transurethral enucleation with bipolar loop for enucleation of lateral lobes, which is characterized by a spatula attached to the standard tungsten wire loop.

Figure 2.

After cystoscopy, resection is made at the 12 o'clock position to enucleate the lateral lobes (a). Mucosa at the apical adenoma is incised circumferentially (b). These grooves are deepened to the level of the surgical capsule. Both of the lateral lobes are enucleated using the transurethral enucleation with bipolar loop with arrest of bleeding (c). Enucleated lobes hanging at the bladder neck are resected using a traditional electrocautery wire loop (d).

Next, mucosa at the apical adenoma was incised circumferentially (Fig. 2b). These grooves were deepened to the level of the surgical capsule. Both of the lateral lobes and middle lobe were dissected off the surgical capsule in a retrograde fashion from the apex towards the bladder using the TUEB loop with arrest of bleeding (Fig. 2c). The TUEB loop moved in exactly the same plane as the surgeon's index finger does when performing open simple prostatectomy. In place of releasing the lobes into the bladder, they were left attached at the bladder neck by a narrow mushroom-like pedicle. Fragmentation of the enucleated lobes hanging at the bladder neck was performed by traditional electrocautery wire loop resection, whereas the devascularized lobes were still connected to the surgical capsule by a narrow pedicle (the ‘mushroom’ technique) [8] (Fig. 2d). General anaesthesia was administered in each case. A 26-F continuous-flow resectoscope (Olympus, Tokyo, Japan) and an Olympus UES-40 SurgMaster (Olympus Europa Holding GmbH) electrical current generator were used with settings of 280 W for cutting and 110 W for coagulation.

Standard TURis was performed. General anaesthesia was administered in each case. A 26-F continuous-flow resectoscope with a standard tungsten wire loop (Olympus) was used. An Olympus UES-40 SurgMaster (Olympus Europa Holding GmbH) electrical current generator was used with settings of 280 W for cutting and 110 W for coagulation.

RESULTS

The characteristics of the patients are shown in Table 1 and the two groups were comparable. As shown in Table 2, the change in haemoglobin at postoperative day 1 in the TUEB group was significantly less than in the TURis group. With a larger prostate ≥ 50 mL, the difference in the change in haemoglobin at postoperative day 1 was significant. Only two patients in the TURis group (3.6%), and none in the TUEB group, underwent blood transfusion. In addition, catheterization time and hospital stay for TUEB were significantly shorter than those for TURis (Table 2). The mean weight of retrieved tissue for TUEB was significantly higher than that for TURis, although there was no significant difference in preoperative prostate volume between TUEB and TURis. Total operating times of TUEB and TURis did not differ significantly.

Table 1. Patient characteristics
CharacteristicTUEBTURis P
  1. TUEB, transurethral enucleation with bipolar; TURis, transurethral resection in saline.

Patients (n)5555 
Age (years), mean71.570.00.267
Preoperative prostate volume (mL), mean65.655.70.062
Preoperative prostate volume ≥50 mL, n (%)36 (65)30 (55)0.243
Urinary retention, n (%)22 (40)20 (36)0.695
Incidental adenocarcinoma, n (%)2 (3.6)1 (1.8)0.558
Table 2. Peri-operative data
VariableTUEBTURis P
  1. POD, postoperative day; TUEB, transurethral enucleation with bipolar; TURis, transurethral resection in saline.

Operating time (min)76.970.20.065
Resected weight (g)41.331.70.007
Resected weight/operating time (g/min)0.540.450.060
Haemoglobin decrease at 1 POD (g/dL)1.081.60<0.001
Haemoglobin decrease at 1 POD in patients with prostate <50 mL (g/dL)1.031.240.203
Haemoglobin decrease at 1 POD in patients with prostate ≥50 mL (g/dL)1.101.90<0.001
Catheterization time (h)44.964.6<0.001
Hospital stay (h)68.988.6<0.001

With regard to treatment efficacy, there were significant improvements in IPSS, QoL scores, Qmax, Qmean, PVR and serum PSA levels in both groups from baseline at the 6- and 12-month follow-ups, although we did not find any statistical difference between the two groups in terms of IPSS, QoL score or uroflowmetry (Table 3). Patients had an 87.5% mean decrease in the serum PSA level after TUEB, whereas they had a 75.5% mean decrease in the level after TURis (P < 0.001). In brief, there was no statistically significant difference between the TUEB and TURis groups throughout the 6- and 12-month follow-ups in these postoperative parameters, except for the decrease in serum PSA level (Table 3).

Table 3. Mean outcome measures from baseline to 6 and 12 months of follow-up
VariableBaseline6-month follow-up12-month follow-up
  1. PVR, postvoid residual urinary volume; Qmax, maximum urinary flow rate; Qmean, mean urinary flow rate; QoL, quality of life; TUEB, transurethral enucleation with bipolar; TURis, transurethral resection in saline.

Qmax (mL/s)   
 TUEB7.123.024.5
 TURis7.022.023.6
 P0.9180.4260.522
Qmean (mL/s)   
 TUEB3.512.415.1
 TURis3.310.414.6
 P0.5960.0060.576
IPSS   
 TUEB20.24.44.5
 TURis21.74.24.1
 P0.1290.4710.319
QoL   
 TUEB5.161.231.22
 TURis5.111.311.49
 P0.7280.6030.073
PVR (mL)   
 TUEB161.024.421.7
 TURis152.325.319.8
 P0.7390.8320.602
PSA level (ng/mL)   
 TUEB8.080.930.86
 TURis8.931.811.77
 P0.5170.0040.001

The early and late complications of both procedures are listed in Table 4. Capsular perforation was present in two TURis patients (3.6%) and one (1.8%) TUEB patient. At 6 months after the operation, one (1.8%) patient in each group reported stress incontinence requiring the use of at least one pad. However, stress incontinence resolved spontaneously and no patient with stress incontinence at the 6-month follow-up remained incontinent at the 12-month follow-up. In the TUEB group, two (3.6%) episodes of acute urine retention after catheter removal were noted compared to three (5.5%) in the TURis group, and these cases were treated with subsequent temporary recatheterization. In addition, two (3.6%) patients in the TUEB group reported urethral stricture compared to three (5.5%) in the TURis group. There was no statistically significant difference between TUEB and TURis for these early and late complications (Table 4).

Table 4. Early and late complications
ComplicationTUEB, n (%)TURis, n (%)
  1. TUEB, transurethral enucleation with bipolar; TURis, transurethral resection in saline. There were no deaths, myocardial infarctions or transurethral resection syndrome episodes.

Early complications  
 Blood transfusion0 (0)2 (3.6)
 Capsular perforation1 (1.8)2 (3.6)
 Bladder mucosal injury0 (0)0 (0)
 Recatheterization2 (3.6)3 (5.5)
 Reoperation0 (0)1 (1.8)
 Urge to urinate4 (7.3)5 (9.1)
Late complications at 6-month follow-up
 Urethral stricture2 (3.6)3 (5.5)
 Stress incontinence1 (1.8)1 (1.8)
Late complications at 12-month follow-up
 Urethral stricture2 (3.6)3 (5.5)
 Stress incontinence0 (0)0 (0)

DISCUSSION

TURP remains the standard surgical therapy for symptomatic BPH [1]. However, TURP causes some morbidity, with potential problems such as bleeding requiring transfusions, as well as TUR syndrome [2,3]. For this reason, substantial interest has been focused on minimally invasive and alternative surgical techniques. Consequently, some endosurgical treatments for BOO secondary to BPH have been developed.

Subsequent to the establishment of the TURis system, TUR syndrome has not been widely seen because of the use of 0.9% saline as the irrigation fluid [5]. The TURis system is as efficacious as monopolar TURP, although it is safer than the latter because of the smaller risk of TUR syndrome [9]. Recent experimental laboratory investigations showed a lower bleeding rate and deeper coagulation capacity with the bipolar armamentarium [10,11]. This could lead to a lower blood loss, fewer transfusions and a reduced risk of clot retention in the clinical setting. Furthermore, the holmium (Ho : YAG) laser has been established as an ideal incisional and ablative tool in endourology because of its shallow penetration depth, excellent haemostatic properties and a capacity for use with normal saline [12]. HoLEP proved to be equivalent to TURP for relieving BOO in men with BPH of any size [13–15]. HoLEP can be an endourological alternative to traditional open simple prostatectomy for extremely large prostates with minimal blood loss, as well as a short catheterization time and hospital stay [16–18]. However, urologists in hospitals that have no laser system cannot endosurgically enucleate prostatic adenoma. Therefore, the bipolar enucleation using the PlasmaKinetic system (Gyrus Medical GmbH, Tuttlingen, Germany) was devised. According to the initial results of a randomized controlled trial comparing HoLEP and PlasmaKinetic enucleation of prostate, bipolar enucleation using the PlasmaKinetic system was as safe and effective as HoLEP [19].

More recently, TUEB, which is a treatment involving blunt adenoma enucleation using only the TUEB loop in addition to the TURis system, has been established. In this procedure, the spatula is analogous to the surgeon's index finger during open prostatectomy, shelling out whole lobes off of the prostatic capsule. TUEB was developed to maintain the equivalent efficacy of adenoma enucleation, such as open prostatectomy or HoLEP, with excellent haemostasis. According to a nationwide survey in Japan, which investigated the trend in surgical procedures for BPH in 2009 including 20 413 operations, endosurgical enucleation, such as HoLEP and TUEB, has dramatically increased, becoming the second most common treatment (n= 3416; 16.7%) after standard TURP and TURis (n= 14 799; 72.5%) [20].

However, to our knowledge, there are few reports on the efficacy and safety of TUEB. Furthermore, there have been no reports comparing TUEB and TURis. The present study aimed to report on the 1-year follow-up results of a trial comparing TUEB with TURis in terms of efficacy and safety. According to a previous study, TUEB led to significant improvements in IPSS, QoL scores and Qmax compared to baseline [21]. In the present study, there were significant improvements in IPSS, QoL scores and uroflowmetry findings compared to those at baseline in patients who underwent TUEB. At all follow-up assessments up to 1 year, there were no significant differences in any of the micturition parameters at any interval in the two groups. Therefore, in the present study, TUEB was as effective as TURis in terms of improved subjective symptoms and uroflowmetry findings at the 6- and 12-month follow-ups.

With respect to peri-operative complications, TUEB is excellent for controlling bleeding during surgery. The TUEB electrode enables the urologist to enucleate tissue with the spatula and then coagulate any bleeding with the loop electrode in quick succession. Because of the lack of bleeding, visibility remains excellent throughout the operation. In the present study, there was a significant difference in the change in haemoglobin at postoperative day 1 between TUEB and TURis, especially in prostate glands > 50 mL. In addition, the transfusion rate was zero in the TUEB group and 3.6% in the TURis group. As a result, TUEB required a shorter catheterization time and hospital stay than TURis. Furthermore, the total operating times of TUEB and TURis did not differ significantly. Therefore, TUEB could be of benefit to most patients who undergo the procedure after surgery.

In the present study, the retrieved tissue weight in those patients who underwent TUEB was significantly higher than in those patients who underwent TURis, although there was no significant difference in preoperative prostate volume between TUEB and TURis. In addition, when preoperative and postoperative PSA levels were compared, patients had an 87.5% mean decrease in PSA level after TUEB, whereas they had a 75.5% mean decrease in PSA level after TURis (P < 0.001). The dramatic reduction in PSA levels after TUEB confirmed the almost complete removal of prostatic adenoma. In the TURP series of Aus et al. [22], which included 190 patients, only a 70% mean decrease in PSA level was reported. Thus, the PSA data and the retrieved tissue weight obtained in the present study support the superior completeness of adenoma removal that can be achieved via TUEB compared to TURis.

The main limitation of the present study resides in its retrospective design. Furthermore, the study analysis was conducted for a limited number of patients, who were only followed for a short time. We were able to record a limited number of events and this weakened the significance of the statistical analysis. The accrual of a prospective study and a larger pool of patients with a longer follow-up period would definitely provide a more accurate picture that may improve the efficacy and safety of TUEB. Nevertheless, we consider that the present study provides favourable peri-operative and 1-year follow-up data for patients who underwent TUEB with regard to both the efficacy and the safety of the surgical instrument. Accordingly, the findings of the present study will help in ameliorating and increasing the treatment options for BPH surgery in men.

On the basis of the results obtained in the present study, we conclude that TUEB is equivalent to TURis in terms of improving symptom-related outcomes, QoL measures and peak urinary flow rates at 6 and 12 months of follow-up. However, TUEB is superior to TURis in several areas, including haemostasis, especially for prostates > 50 mL, catheterization time, hospital stay and the amount of tissue removed from prostates of equivalent size on ultrasonography. Furthermore, no severe adverse events were found in patients who underwent TUEB. Early and late complications were similar and rare with the two procedures. These results indicate that TUEB is a safe and minimally-invasive technique that improves symptoms and uroflowmetry findings as a result of BOO in patients with BPH. Therefore, TUEB could represent a novel surgical treatment for managing BPH.

In conclusion, TUEB is a safe and minimally-invasive technique that was shown to be equivalent to TURis in terms of improving symptom-related outcomes, QoL measures and peak urinary flow rates at 6 and 12 months of follow-up. TUEB was associated with a lower blood loss, as well as a shorter catheterization time and hospital stay compared to TURis.

ACKNOWLEDGEMENTS

The authors would like to thank Yumi Furuki (Saitam, Japan) for help with the data collection and statistical analysis.

CONFLICT OF INTEREST

The authors declare that there are no conflicts of interest.

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