Holmium:YAG Transurethral Incision Versus Laser Photoselective Vaporization for Benign Prostatic Hyperplasia in a Small Prostate Ahmed M. Elshal, Mohamed A. Elkoushy, Hazem M. Elmansy, John Sampalis and Mostafa M. Elhilali*, From the Division of Urology (AME, MAE, HME, MME), and Division of Epidemiology & Biostatistics (JS), Department of Surgery, McGill University Health Center, Montreal, Quebec, Canada; Urology and Nephrology Center, Mansoura University, Mansoura (AME), and Urology Department, Suez Canal University, Ismailia (MAE), Egypt Abbreviations and Acronyms BNC ¼ bladder neck contracture BOO ¼ bladder outlet obstruction BPH ¼ benign prostatic hyperplasia CAD ¼ Canadian dollars Hol ¼ holmium HoLEP ¼ holmium laser enucleation of prostate I-PSS ¼ International Prostate Symptom Score KTP ¼ potassium titanyl phosphate LBO ¼ lithium triborate PVP ¼ photoselective vaporization of the prostate PVR ¼ residual urine Qmax ¼ maximal flow rate QOL ¼ quality of life score TOV ¼ trial of voiding TRUS ¼ transrectal ultrasound TUIP ¼ transurethral incision of prostate TURP ¼ transurethral resection of prostate YAG ¼ yttrium-aluminum-garnet Purpose: We assess the perioperative, short-term and long-term functional outcomes of treating bladder outlet obstruction secondary to a small prostate by 1 of 2 laser techniques. Materials and Methods: A retrospective review using a prospectively maintained database was performed of patients treated for bladder outlet obstruction secondary to a prostate smaller than 40 ml. Patients who were treated with GreenLightÔ photoselective vaporization of the prostate or holmium laser transurethral incision of the prostate were included in the study. Results: From January 2002 through December 2010, 191 cases of 1,682 laser prostate surgeries were described. GreenLight photoselective vaporization of the prostate was performed in 144 (75.4%) cases and holmium laser transurethral incision of the prostate was performed in 47 (24.6%) cases. A significantly shorter mean operating time, hospital stay and catheter duration were observed in the holmium laser transurethral incision of the prostate group (30.3 16 minutes, 0.8 0.8 days and 1.3 1.9 days, respectively) than in the photoselective vaporization of the prostate group (45.8 22 minutes, 0.3 0.4 days and 0.4 0.6 days, respectively, p <0.05). At 1 and 5 years after photoselective vaporization of the prostate there were reductions in mean International Prostate Symptom Score, quality of life score and residual urine with improvement in mean maximal flow rate of 57.7% and 62.8%, 58.3% and 57.2%, 65.4% and 73%, and 127.6% and 167.1%, respectively. At 1 and 5 years after holmium laser transurethral incision of the prostate there were reductions in mean International Prostate Symptom Score, quality of life score and residual urine with improvement of mean maximal flow rate of 55.3% and 52.8%, 49.2% and 49%, 45% and 78.1%, and 67.4% and 35.4%, respectively. Subjective and objective urine flow parameters were comparable at different followup points. There was no significant difference between the 2 groups in terms of early and late complications (p >0.05). Reoperation rates were 10.4% and 6.4% in the photoselective vaporization of the prostate and holmium laser transurethral incision of the prostate groups, respectively (p >0.05). The mean estimated cost per holmium laser transurethral incision of the prostate procedure was significantly Accepted for publication June 28, 2013. * Correspondence: Department of Urology, McGill University, Royal Victoria Hospital, 687 Pine Ave. West, Room S6.95, Montreal, Quebec H3A 1A1 Canada (telephone: 514-843-1516; FAX: 514-843-1552; e-mail: mostafa.elhilali@muhc.mcgill.ca). Financial interest and/or other relationship with AMS, Boston Scientific, Lumenis, Astellas Canada, Ferring Canada, Pfizer Canada, Eli Lilly and Sophiris. 148 j www.jurology.com 0022-5347/14/1911-0148/0 THE JOURNAL OF UROLOGY 2014 by AMERICAN UROLOGICAL ASSOCIATION EDUCATION AND RESEARCH,INC. http://dx.doi.org/10.1016/j.juro.2013.06.113 Vol. 191, 148-154, January 2014 Printed in U.S.A.
COMPARISON OF LASER TECHNIQUES FOR BENIGN PROSTATIC HYPERPLASIA 149 lower than per photoselective vaporization of the prostate procedure (509.34CAD vs 1,765.92CAD, p ¼ 0.002). Conclusions: Holmium laser transurethral incision of the prostate and GreenLight photoselective vaporization of the prostate seem to be equally effective, safe and durable surgical treatment options for small prostates even in high risk patients. Key Words: laser therapy, prostatic hyperplasia, transurethral resection of prostate, holmium IN the era of minimally invasive surgery the advantages of lasers in the treatment of bladder outlet obstruction secondary to benign prostatic hyperplasia were shown regardless of prostate size. Prostate laser ablation has been associated with great enthusiasm throughout the last decade, particularly with the evolution of GreenLight (532 nm) laser technology. The intraoperative safety and long-term efficacy are evident. 1,2 However, with prostate laser vaporization techniques the added safety with the shorter hospital stay, catheterization duration and convalescence period were associated with a need for reoperation for various reasons. 3 Moreover, in many reports laser vaporization of smaller prostates was associated with relatively more frequent cases of bladder neck contracture with a subsequent need for incision procedures due to scarring of the bladder neck. 1,4 Many years ago Orandi reported the efficacy of transurethral incision of the prostate using a hot Collins knife for the relief of BOO secondary to a small prostate with durable outcomes and a limited reoperation rate. 5e7 With the introduction of holmium laser energy we have an alternative tool to incise the prostate. Hol-TUIP is a simple, fast and effective procedure for the relief of BOO, with added safety, particularly for high risk/anticoagulated cases. 8,9 The increased use of available medical therapy for BPH is associated with a shift in the target population presenting for prostate surgery. At the time of surgery, patients are now older and have more comorbidities. The advantages of laser prostate surgery have been clearly shown in older patients, eg octogenarians, patients on ongoing anticoagulants/ antiplatelets and those with implanted cardiac pacemakers. 10 Although these patients are also presenting with larger prostates, small prostates (less than 40 ml) still represent 15% to 20% of our cases at a tertiary referral prostate center. In this study the short-term and long-term outcomes of GreenLight (532 nm laser) PVP and Hol-TUIP are compared as treatment for BOO secondary to a small prostate. PATIENTS AND METHODS Study Design A retrospective review was conducted using our prospectively maintained laser prostate database for patients who were treated for BOO secondary to a small prostate. Patients with prostates 40 ml or smaller based on preoperative TRUS and treated with GreenLight (532 nm laser) PVP or Hol-TUIP were included in the study. Exclusion criteria were previous prostate surgery, diagnosed prostate cancer, chronic retention and grossly enlarged median lobe on initial cystoscopy. Intervention All procedures were performed or supervised by a single surgeon (MME) and the choice of technique was based on surgeon discretion. A modified continuous flow 26Fr resectoscope with a distal bridge to stabilize the laser fiber, continuous saline irrigation and a video system were used. Hol-TUIP was performed using a 100 Watt holmium:yag laser (VersaPulseÒ) and a 550 nm endfiring fiber (SlimLineÔ 550). A deep incision of the bladder neck at 5 and or 7 o clock using laser energy to create a trough down to the capsule was performed with distal extension just lateral to the verumontanum. The laser setting was E ¼ 2, r ¼ 50 for cutting and E ¼ 1.5, r ¼ 30 for hemostasis (fig. 1, A). GreenLight (532 nm) PVP was performed with a previously described technique. 11 A side to side sweeping technique was used with the side-firing fiber moving from the area of the bladder neck to approximately the level of the verumontanum. The lowest applicable energy setting (60 to 80 W) was used during apical and bladder neck vaporization. The fiber-tissue distance was within the limits of 1 mm for the KTP (80 Watt) and 1 to 3 mm for the LBO (120 Watt) laser. As much as possible the end point of the laser procedure was a TURP-like cavity lined by capsular fibers, as judged by the operator (fig. 1, B). A standard 22Fr Foley 2-way catheter was inserted and connected to straight drainage unless the degree of hematuria required bladder irrigation. Intermittent bladder irrigation was delivered through a Y connector. On rare occasions if the hematuria persisted despite intermittent irrigation, a 3-way catheter with continuous irrigation was used. Once the urine was clear the catheter was removed, and when the patient was able to void adequately he was discharged home. Outcome Measures Primary. The change in subjective (I-PSS and QOL) and objective (Qmax and PVR) urinary parameters at different points of followup were assessed and compared. Secondary. Operative time, catheter duration, hospital stay and postoperative adverse events (early and late) were reported and graded using the modified Clavien scale, and compared among study groups.
150 COMPARISON OF LASER TECHNIQUES FOR BENIGN PROSTATIC HYPERPLASIA Figure 1. Hol-TUIP (A) and PVP with GreenLight HPSÒ (B) Tertiary. This measure was the cumulative health resources related cost analysis of both procedures from a local institutional perspective (actual cost). Perioperative costs included operating room occupancy, theater consumables, irrigation fluid used, disposable medical devices (laser fibers) and hospital stay. Postoperative costs included unplanned clinic/emergency visits and reoperations. The capital equipment cost was not included as this was donated to the hospital. Identical costs were not included such as medical staff fees, operating room setup and disinfection of disposables. Statistical Analysis Data analysis was conducted using the commercially available SPSSÒ version 20 for Mac Ò. Results were compared between treatment groups using the chi-square test for categorical variables and the Mann-Whitney U test for quantitative variables. The paired t-test was used for the assessment of change in continuous measures at different followup points. To control for confounding through bias by indication a propensity score was developed. A logistic regression model was used to assess the effect of different parameters on the treatment used, and several parameters were tested including baseline TRUS, baseline prostate specific antigen, age at surgery, indication for surgery and use of catheter. A backward stepwise selection procedure was used to select the final model predicting treatment allocation. The variables included in the final model were baseline TRUS and presence of catheter. The predicted probability of treatment was used as the propensity score in the multivariate analyses.
COMPARISON OF LASER TECHNIQUES FOR BENIGN PROSTATIC HYPERPLASIA 151 RESULTS From January 2002 through December 2010, 191 cases met the inclusion criteria of 1,682 laser prostate surgeries in our prospectively maintained database. GreenLight PVP was performed in 144 (75.4%) cases (48 with KTP [80 Watt] and 96 with LBO [120 Watt]) and Hol-TUIP was used in 47 (24.6%) cases. Baseline Criteria Among the noncatheterized patients there were no significant differences in median preoperative I-PSS and Qmax between the study groups (p ¼ 0.41 and 0.2, respectively, fig. 2). Table 1 shows the baseline criteria of the study groups and preoperative TRUS sizing. The number of catheterized patients (those with urinary retention) was significantly higher in the PVP group. To assess the outcome parameters without confounding bias for treatment allocation, both variables were used for the development of a propensity score for the treatment predicted probability. Perioperative Findings Laser energy use, operative time, hospital stay and time to catheter removal were significantly less in the Hol-TUIP group (p <0.05, table 1). No blood transfusion was needed in any of the study groups. Operative bleeding and impaired visibility necessitating electrocautery loop for hemostasis occurred in 6.2% of the PVP group. In-hospital retention necessitating repeat TOV was observed in 6 patients in the PVP group (table 2). Outcome Measures At 1 and 5 years after PVP there were reductions in mean I-PSS, QOL and PVR with improvement in mean Qmax of 57.7% and 62.8%, 58.3% and 57.2%, 65.4% and 73%, and 127.6% and 167.1%, respectively. At 1 and 5 years after Hol-TUIP there were reductions in mean I-PSS, QOL and PVR with improvement in mean Qmax of 55.3% and 52.8%, 49.2% and 49%, 45% and 78.1%, and 67.4% and 35.4%, respectively. In both groups there were significant reductions in mean I-PSS and QOL between baseline scores and at all points of followup (paired t-test p <0.05, fig. 2). Similarly, mean Qmax and PVR showed significant improvement from baseline measures at all points of followup (paired t-test p <0.05, fig. 2). There was no significant difference between the 2 groups in terms of symptom score and flow rate at different points of followup (p >0.05). However, Qmax at 5 years in the Hol-TUIP group (mean 12.16, median 12.1, range 5.4 to 19.4 ml per second) was significantly lower than in the PVP group (mean 20.3, median 19.3, range 7.4 to 34.5, p ¼ 0.03, fig. 2). After adjusting for bias by indication using propensity score there were no differences between the 2 procedures regarding change in any of the primary outcome parameters. This finding was also confirmed using repeated measures models. Negative Events Table 2 summarizes postoperative complications (early and late) based on a modified Clavien scale after 42 and 43.4 months median followup after PVP and Hol-TUIP procedures, respectively. There were no statistically significant differences between the 2 groups in terms of early and late complications or when assessed grade by grade based on a modified Clavien scale (p >0.05). The reoperation rate was 10.4% and 6.4% in the PVP and Hol-TUIP groups, respectively (p >0.05). Redo for BNC was performed in 9 cases (6.2%) in the PVP group and in 1 case (1.2%) in the Hol-TUIP group. However, this did not reach statistical significance (p >0.05). Re-treatment for regrown adenoma was indicated in 1 patient in the PVP group. Cost Analysis We accounted for a single laser fiber per procedure for the PVP group and a single laser fiber for 20 procedures in the Hol-TUIP group, the cost of reoperations exclusively as outpatient procedures and all the aforementioned parameters in our calculations. Total costs were 1,256.36CAD higher (95% CI 832.1CAD:1,690CAD) in the PVP group. The mean estimated cost per Hol-TUIP procedure was significantly lower than per PVP procedure (509.34CAD vs 1,765.92CAD, p ¼ 0.002). The higher cost of PVP was mainly due to the cost of a single use laser fiber (802.5CAD extra) and a significant difference in hospital admission time (480CAD extra). DISCUSSION The surgical treatment of BOO secondary to a small prostate is not frequently debated in the urological literature. However, the limited morbidity and comparable functional outcomes of transurethral laser prostate techniques make them an attractive alternative that fits the needs of a growing sector of fragile surgically treated patients. 10 Furthermore, a recent meta-analysis of trials comparing GreenLight PVP to TURP showed an equivalent efficacy profile with the added benefits of using saline as an irrigant, no transurethral resection syndrome, and shorter hospital stay and catheter time. 12 A recent multicenter prospective assessment of TURP morbidity showed a 2% transfusion rate, 1.2% transurethral resection syndrome rate, 0.09% mortality rate and 5.2% early surgical revision rate for treating a small prostate. 13 Laser surgery for a
152 COMPARISON OF LASER TECHNIQUES FOR BENIGN PROSTATIC HYPERPLASIA Figure 2. Changes in symptom score and flow rate after PVP (A and C ) and Hol-TUIP (B and D), and percentage of evaluable subjects at different points (E ). small prostate has the advantage of being less morbid and potentially being performed as an outpatient procedure. A pulsed mode holmium laser (2,123 nm) has a hemostatic advantage over the continuous mode GreenLight laser (532 nm). This advantage was Table 1. Baseline and perioperative criteria PVP Mean SD age at surgery/median (range) Mean SD ng/dl preop prostate specific antigen/median (range) Mean SD ml prostate size by TRUS/median (range) No. for each indication (%): Lower urinary tract symptoms refractory to medical therapy Acute urine retention þ failed TOV No. on ongoing anticoagulants (%) No. American Society of Anesthesiologists score III or greater (%) Mean SD KJ energy used/median (range) Mean SD mins operating time/median (range) No. monopolar electrocautery for hemostasis (%) No. concomitant cystolithotripsy (%) No. continuous bladder irrigation (%) Mean SD days catheterization/median (range) Mean SD days hospital stay/median (range) 69.2 11/69.8 1.7 2.5/1.09 29.4 7.1/30 (48e93) (0.1e22) (15e40) 113 (78.4) 31 (21.6) 27 (18.7) 21 (14.5) 114.8 56/106.4 (12.2e277) 45.8 22/45 (8e120) 9 (6.2) 5 (3.6) 3 (2) 1.3 1.9/1 (0e20)* 0.8 0.8/1 (0e7)* * For 0 days patients were discharged home/catheter was removed on day of surgery a few hours later. Hol-TUIP p Value 72.4 7.5/71.4 (56e90) 2.3 4.5/1.1 (0.3e26.7) 25.8 6.8/27 (10e40) 0.12 0.46 0.007 0.01 44 3 13 11 54.8 30.3 0 2 0 0.4 0.3 (93.7) (6.3) (27) (23.4) 24.3/50.9 (10.9e107) 16/26 (10e70) (4.3) 0.6/0 0.4/0 (0e3)* (0e1)* 0.2 0.3 0.000 0.001 0.11 0.7 0.4 0.000 0.000
COMPARISON OF LASER TECHNIQUES FOR BENIGN PROSTATIC HYPERPLASIA 153 Table 2. Postoperative complications (early and late) according to modified Clavien scale No. PVP (%) No. Hol-TUIP (%) p Value Management Grade II: Inability to void (retention): Early (1st mo/failed TOV) 6 (4.2) 0 0.4 Re-catheterization þ repeat TOV Clot retention 0 0 Late (acute urinary retention) 0 0 Postop hematuria 1 (0.7) 0 1 Conservative (bladder irrigation) Urinary tract infections 0 1 (2.1) 0.24 Culture based antimicrobial Recurrent/persistent lower urinary tract symptoms 6 (4.2) 2 (4.3) 1 Anticholinergic medications Anemia necessitating transfusion 0 0 0 Blood/blood products transfusion Capsule perforation 1 (0.7) 0 0.3 Prolonged catheterization Persistent urge urinary/stress urinary incontinence (more than 1 yr) 3 (2.1) 0 1 Anticholinergic medications þ Kegel exercises Grade II d: Chronic retention 1 (0.7) 0 1 Clean intermittent catheterization Grade III a: Operative bleeding þ impaired visibility 9 (6.2) 0 0.1 Monopolar electrocautery for hemostasis Prostate adenoma (residual/regrowth) 1 (0.7) 0 1 Redo PVP BNC 9 (6.2) 1 (2.1) 0.45 Bladder neck incision (holmium laser incision) Urethral stricture 5 (3.5) 2 (4.3) 0.68 Visual internal urethrotomy clearly reflected in the 6.2% operative bleeding and impaired visibility of PVP in the current cohort. The use of auxiliary procedures (electrocautery) to complete hemostasis with PVP was reported in 1.8% to 10.3% of cases. 3,4,14,15 The GreenLight laser beam may cause craters cutting blood vessels below the surface of the ablated prostate. Control of this form of bleeding with this continuous wavelength, especially with impaired visibility due to bleeding, may represent a minor surgical challenge. 3 In this cohort there was similar symptom improvement at different points in the 2 groups. However, the degree of improvement in flow rate was higher in the PVP group, which could reflect the degree at which the flow control zone was opened. BNC is one of the most common causes of retreatment after any surgical treatment of BOO due to BPH, particularly in patients with smaller prostates. 1,4,13,16 Recently BNC rates have been shown to be as high as 8.6% after PVP. 17 Even many of the described techniques of PVP entail an incision procedure (eg vaporization incision technique). 18 A relatively high BNC rate (1.1% to 8.6%) has been reported in series of PVP with KTP (80 Watt) as well as LBO (120 Watt). 1e4,19 In a randomized trial of Hol-TUIP vs HoLEP for the treatment of a small prostate (less than 40 ml) Aho et al demonstrated that Hol-TUIP can be performed more rapidly than HoLEP with equivalent catheter and hospital times. 8 There was significantly more early stress incontinence postoperatively in the HoLEP group but no bladder neck contractures were detected. Although Hol-TUIP is feasible as an outpatient simple procedure in patients with a small prostate, this report showed a 20% reoperation rate for residual adenoma. However, the authors did not comment on the prostate morphology at the initial cystoscopic assessment, which we believe is an integral part of the decision making process, as important as the size. 8 These findings of Aho et al highlighted the need to balance the risk of leaving obstructing prostate tissue with an incision procedure 8 against the growing evidence of the increased risk of BNC with nonincision procedures for a small prostate. 1,4 The holmium:yag laser has been used successfully for the treatment of different degrees of BPH with different techniques of incision, resection and enucleation. 9,20,21 Furthermore, long-term data after laser ablation of a small prostate showed a similar BNC rate regardless of the wavelength of the laser used, either GreenLight (532 nm) or holmium:yag (2,123 nm). 22 In the current cohort we showed that the Hol-TUIP procedure provides symptom reduction equivalent to that of PVP at different followup points. In addition, a shorter operating time, catheter duration and hospital stay were shown with Hol-TUIP. These findings were reflected in the total cost of the procedure, with savings of almost 1,200CAD per procedure from the actual cost. For others using single use holmium laser fibers, the cost savings would be less. In a study by Fraundorfer et al holmium laser resection of the prostate was more cost-effective than TURP because of savings in hospital stay, the need for postoperative nursing care and not needing blood transfusion. 23 Furthermore, on the basis of these savings 93 cases per year were required to recover the capital and service costs of the holmium:yag laser. Head-to-head cost analyses of different laser procedures are currently lacking in the urological literature. Cornford et al described Hol-TUIP as a totally outpatient procedure. 9 However, in our series hospital admission was individualized based on specific patient morbidity. PVP and Hol-TUIP can be performed safely as a day surgery, which will contribute
154 COMPARISON OF LASER TECHNIQUES FOR BENIGN PROSTATIC HYPERPLASIA to cost savings. Furthermore, similar perioperative morbidity and re-treatment rates were reported for the 2 procedures. Despite being statistically insignificant, the relatively higher BNC rate in the PVP group warrants randomized evaluation and comparison of the groups to reach a solid conclusion regarding the results of the current cohort. In terms of study limitations, the retrospective nature of our study is the main limitation in addition to the disparity in sample size, relatively high dropout rate especially at 5 years and the lack of evaluation of sexual function. However, to the best of our knowledge, this study is the first to compare these techniques of laser prostate surgery with a relatively long followup. Furthermore, the statistical model using the propensity score nullifies the bias effect of procedure selection on the outcome parameters. CONCLUSIONS Hol-TUIP and GreenLight PVP seem to be equally effective, safe and durable surgical treatment options for small prostates even in high risk patients. However, in a small prostate (less than 40 ml) with absence of a median lobe Hol-TUIP was associated with a lower reoperation rate for BNC, fewer hospital readmissions and a lower overall cost. Both techniques can be offered safely as outpatient procedures. REFERENCES 1. Elshal AM, Elmansy HM and Elhilali MM: Can we predict the outcome of 532 nm laser photoselective vaporization of the prostate? Time to event analysis. J Urol 2012; 188: 1746. 2. Hai MA: Photoselective vaporization of prostate: five-year outcomes of entire clinic patient population. Urology 2009; 73: 807. 3. Tas c i AI, Ilbey Y O, Luleci H et al: 120-W Green- Light laser photoselective vaporization of prostate for benign prostatic hyperplasia: midterm outcomes. Urology 2011; 78: 134. 4. 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