Vaporization of the Prostate


Fig. 16.1

Cystoscopy prior to initiating the photoselective vaporization of the prostate demonstrates significant benign prostatic hyperplasia with complete visual obstruction by the median lobe (a) and lateral lobes (b). The bladder neck is not visualized from the verumontanum


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Fig. 16.2

Nodules of benign prostatic hyperplasia within the mid-prostatic urethra are visually obstructing the bladder neck



After introduction of the laser fiber, the PVP is begun. General strategies for achieving the most efficient vaporization are pursued. These include maintaining only a 1–2 mm distance between the laser fiber and the tissue being treated, rotating the fiber no more than 30° from the neutral position to prevent diffusion of the laser beam, keeping the rotation of the fiber at a slow pace (0.5–1 sweeps/s), and withdrawing the cystoscope at a speed of only a few millimeters per second. The speed of the fiber rotation and the angle of the rotation have been shown to have effects on vaporization efficiency in ex vivo analysis [12, 13]. The fiber is marked with a blue arrow and a red stop sign (Fig. 16.3) to help prevent firing the laser toward the cystoscope lens, and careful attention must be given to observing these markings. In addition, the cystoscope is rotated within the prostatic urethra so that the beak of the scope is always 180° from the tissue being treated. The appearance of bubbles as the tissue is being treated is a reliable indicator of effective vaporization. The initial power settings are 80 W for vaporization and 30 W for coagulation. The vaporization power is increased to 120 W once enough tissue has been cleared in the prostate fossa that the working channel can be easily traversed without the laser fiber being forced into contact with the prostate tissue. The vaporization power is increased to 180 W as necessary for the largest or most fibrous glands.

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Fig. 16.3

The 120 W HPS 2090 fiber (a) and the 180 W XPS MoXy fiber (b) are shown at the optimal extension from the end of the cystoscope and the proper distance from the tissue being treated. The blue arrows demonstrate that the beams are aimed toward the tissue and away from the lens


The authors’ technique for completing the PVP begins first by performing vaporization at the 5 o’clock and 7 o’clock positions from the bladder neck to the level of the verumontanum in order to help distinguish the lateral lobes from the median lobe and to define the surgical level of the capsular fibers. The right and left lateral lobes are vaporized next by performing sweeps from the bladder neck to the verumontanum in a stepwise progression from the posterior aspect of the lobe to the anterior aspect of the lobe on each side. The treatment continues in this fashion until the circular fibers of the prostate capsule are recognized (Fig. 16.4). The median lobe of the prostate is then vaporized from a lateral to medial direction beginning at the bladder neck and proceeding distally to the verumontanum . The median lobe is approached from both lateral directions in this manner until the posterior bladder neck is completely flattened to the level of the trigone. Care is taken to recognize the ureteral orifices, which can be marked at the start of the procedure by applying a short burst of vaporization or coagulation energy to the nearby bladder mucosa. Any residual apical tissue is vaporized to complete the procedure and allow a fully unobstructed view from the verumontanum through the prostatic urethra (Figs. 16.5 and 16.6). This technique is very similar to that described by Malek [17] and the Basel technique [14]. Those patients with a large median lobe may require partial or complete vaporization of the median lobe prior to the lateral lobes in order to optimize visualization and irrigation.

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Fig. 16.4

The proper depth of surgical resection is reached once the circular fibers of the prostate capsule are seen


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Fig. 16.5

The verumontanum is preserved during photoselective vaporization of the prostate (PVP) (a), and vaporization is not performed on tissue distal to it in order to minimize risk of thermal injury to the external sphincter. At completion of the PVP, an open channel is seen from the verumontanum to the bladder neck. It is not unusual to see a shaggy surface (b) within the fossa after a successful PVP


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Fig. 16.6

When viewed from the mid-prostatic urethra, any visual evidence of obstruction by prostate tissue is absent (a), and the bladder neck is wide open at the completion of the photoselective vaporization of the prostate (b)


A modified technique that utilizes deep incisions into the prostate lobes has been described [10]. A midline incision that is carried down to the trigone is performed first. A second incision is then made lateral to the median lobe on one side, and the tissue in between these incisions is completely vaporized. The same maneuver is then performed on the contralateral side. Incisions high on the lateral lobes are then made, and the tissue of the lateral lobes is vaporized down to the floor of the prostate.


A spiral technique is another method to perform the PVP [18]. In this technique, a clear channel is achieved in a stepwise fashion, as if spiraling down through the prostate. A complete area of the prostate along its length is vaporized in a 360° manner beginning at the bladder neck, proceeding next to the proximal lateral lobes, and finishing with the floor of the prostate and the apex.


The anterior start technique initially begins with vaporization between the 11 o’clock and 1 o’clock positions from the bladder neck proximally to the level of the verumontanum distally [18]. Vaporization of the lateral lobes is performed next. The median lobe is flattened, and creation of a midline incision through the median lobe then allows completion of its vaporization in a medial to lateral direction bilaterally.


Whichever technique a surgeon utilizes, it should be consistent and reproducible, yet also be applicable to prostates of various sizes and shapes. The procedure is assessed for completion when the inflow irrigation is stopped and the prostate fossa is viewed with the cystoscope placed at the verumontanum (which should still be preserved). A wide-open channel into the bladder should be seen with no remaining visually obstructing tissue present. A TURP-like defect is considered critical to reduce the risk of the patient needing a secondary procedure (see Figs. 16.5 and 16.6). The ureteral orifices are inspected to ensure they remain intact. Stopping the inflow irrigation also allows for assessment of bleeding from the prostate fossa.


There are various techniques for managing troublesome bleeding encountered during the PVP. Raising the height of the irrigation fluid will often improve visualization. Once the view becomes less bloody, the fluid may be lowered to its initial height. Specific sites of bleeding within the fossa may be vaporized using the coagulation setting of the laser. Care should be taken to avoid aiming the beam directly into a bleeding vessel. The vaporization setting can also be used to achieve hemostasis by moving the laser fiber an increased distance away from the tissue being treated and thus defocusing the beam. Coagulation rather than vaporization occurs as the working distance from the fiber to the tissue is increased. If visualizing is adequate to allow for continued safe vaporization, bleeding will often slow or stop as the prostatic channel size is increased, and the flow of the continuous irrigation becomes more vigorous. It is often helpful to focus on vaporizing the lateral lobe contralateral to an annoying bleeding site for a period of time and then periodically reassessing the status of the bleeding as the flow improves. If the degree of bleeding becomes significant enough that visualization is impaired to the point that vaporization cannot be safely continued, it may be necessary to remove the cystoscope and place a resectoscope to achieve hemostasis. Once the bleeding site has been fulgurated with the resectoscope, the cystoscope can be replaced and the PVP completed, or the procedure may be completed as a TURP. The need for placing the resectoscope to control bleeding should be a rare event and in the authors’ experience occurs in less than 1% of cases.


Once the PVP is deemed complete, and the hemostasis at the end of the procedure deemed appropriate, the cystoscope is removed and an 18 Fr Foley catheter is placed. If no bloody drainage is noted from the Foley after the bladder is completely drained, then it is connected to a gravity drainage bag and the patient reversed from anesthesia. If continuous bloody drainage is noted from the Foley, then several minutes of hand irrigation with a bulb or piston syringe is undertaken to see if this is able to clear the urine. If this maneuver is unsuccessful, then the 18 Fr Foley is removed and replaced by a larger-sized three-way catheter. If the urine appears to be clearing on moderate continuous bladder irrigation, then the patient is reversed from anesthesia. In the rare event that the urine does not clear with continuous bladder irrigation and an arterial bleeder is suspected, then a resectoscope should be placed and the bleeding site fulgurated if found.


The authors wish to highlight a few “tricks of the trade” points to keep in mind when performing PVP, especially early in the learning phase:



  • Be sure to review the online physician videos and resource downloads on the Boston Scientific website (http://​www.​bostonscientific​.​com/​en-US/​products/​lithotripsy/​greenlight-xps/​healthcare-professionals-resources.​html).



  • Take advantage of the GreenLight PVP simulator, as this should be useful for urologists learning this technique.



  • At the start of the case, create a good working channel within the prostatic urethra in order to optimize flow of irrigation. The laser power may initially need to be kept low (80 W) when making this channel. The vaporization power can be increased (120 W or higher) once the channel is open enough to allow for good flow of irrigant.



  • Control bleeding early and don’t fall behind on this, as the combination of blood and saline irrigant makes endoscopic visualization difficult.



  • Over time, one’s efficiency of movement and sweeping of the laser fiber improves, and surgeons will find that they will spend more time with their foot on the firing pedal than not.



  • Fully vaporize an area of tissue before moving on to another area, as previously treated tissue becomes more difficult to vaporize, thus decreasing laser efficiency.



  • Choose straightforward cases to start with when early in the learning curve. These cases include patients with smaller glands, who are not on anticoagulation, who are not in retention, and who do not have significant median lobes.



  • Emphasize practice-based learning and improvement strategies by videotaping your procedures and evaluating and critiquing yourself and others. Much can be learned by even a few minutes of doing so!


Postoperative Management


The need for postoperative catheterization following PVP done under general anesthesia is at the discretion of the surgeon. Those done under spinal anesthesia may benefit from overnight placement of a catheter given the increased risk of urinary retention following spinal anesthesia. It is the standard practice of the authors to leave a catheter overnight in patients undergoing PVP, and the patient is instructed to remove the catheter himself on the first postoperative morning if the urine does not demonstrate any significant hematuria. Those patients taking oral anticoagulant medication may benefit from a longer trial of catheterization in order to reduce the risk of clot retention. Those patients with preoperative urinary retention may also benefit from longer catheterization times and a formal trial of voiding in the office rather than self-removal of the catheter at home. Several clinical trials have demonstrated reduced mean catheterization times for patients undergoing PVP relative to TURP [4, 6, 19].


Those patients noted to have significant hematuria at the completion of the PVP often require additional interventions to help the urine to clear. Instilling more water into the catheter balloon and placing it on traction will often help to stop bleeding from the prostate fossa. Manual irrigation of the catheter is also often successful in slowing bleeding and preventing clot formation. However, for those patients in whom significant hematuria persists despite these maneuvers, a period of time utilizing continuous bladder irrigation may be necessary. The continuous bladder irrigation may be weaned over several hours so that the patient may still go home the day of surgery, although in some cases overnight hospitalization may be necessary.


Patients are encouraged to increase their fluid intake as soon as they are transferred from the recovery room to the outpatient unit. This increased fluid consumption should be maintained for several days after surgery, and oral intake and diet can return to preoperative levels if the urine remains clear at home with the catheter out. Narcotic pain medications should be avoided if possible, but patients are given a prescription to fill if necessary. Patients are advised to limit postoperative activities for 1–2 weeks after surgery. Lifting should be restricted to less than 10 lb, and strenuous exercise should be avoided. Sexual activity is also discouraged for 1–2 weeks.


Patients can generally discontinue any medications they were taking for management of LUTS after they have undergone a PVP. Those patients who experience persistent gross hematuria may benefit from the initiation or resumption of a 5-ARI. Similarly, postoperative storage symptoms including urinary frequency, urgency, and urge incontinence may warrant continuation of an antimuscarinic medication in those taking these preoperatively or initiation of such medications for patients in whom these symptoms develop de novo after surgery. Resumption of oral anticoagulant medications can be advised at the surgeon’s discretion and as deemed appropriate by the patient’s cardiologist or internist.


Patients are typically seen in 2–3 weeks following surgery for a postoperative visit or in 2–3 days if a formal trial of voiding is needed. Problems such as dysuria, storage symptoms, hematuria, tissue sloughing, or other concerns are addressed at the postoperative visit. A PVR is routinely checked to rule out impending urinary retention. The patients then return in 3 months for uroflowmetry, assessment of PVR, and assessment of LUTS with the AUA-SI. Any lingering concerns are sought, and those patients with poor symptom relief or very poor flow rates on uroflowmetry undergo cystoscopy to evaluate for incomplete tissue removal, urethral stricture, or bladder neck contracture. A serum PSA can be checked in appropriately selected patients to establish a new baseline for future screening.


Efficacy


Assessment of the efficacy of PVP with regard to improvement in LUTS and urodynamic parameters is limited by a paucity of randomized clinical trials comparing PVP to other established surgical treatment options. In addition, the studies which have been published do not typically utilize the latest iteration of the device, the 180 W XPS system. Nonetheless, the data thus far demonstrate comparable improvement to that achieved with TURP and OP, with potential benefit in regard to surgical complications.


In 2006, Bouchier-Hayes and associates published a randomized trial comparing TURP to PVP done with the 80 W system [4]. A similar reduction of approximately 50% in IPSS was seen for both the PVP and the TURP groups. The Qmax improved by 167% for the PVP patients and 149% for the TURP patients, a significant increase for both. Post-void residual volumes also showed significant decreases, and similar trends were seen in relation to bother and quality of life scores. The length of catheterization was less in the PVP group (mean of 12.2 h) than in the TURP group (44.5 h). A significant difference in length of stay was also noted, with the mean of the PVP group being 1.08 days and the mean of the TURP group being 3.4 days.


An early study comparing TURP to 80 W PVP in patients with large (>70 mL) prostates noted a significant difference in IPSS, Qmax, and PVR values at 6 months in favor of TURP [6]. The procedure was significantly shorter for the TURP group (mean of 51 min versus 87 min), but the length of hospital stay (4.8 days versus 2 days) and length of catheterization (3.9 days and 1.7 days) were shorter in the PVP group.


A study comparing 120 W PVP with TURP in patients with a mean prostate volume of approximately 60 mL shows more promising results [2]. As seen in the other studies, the mean catheterization time of 1.4 days in the PVP group was significantly shorter than the 2.7 days in the TURP group. Mean hospital stay also favored PVP (2.3 days versus 4.1 days). Functional outcome with regard to increase in Qmax, decrease in IPSS, and decrease in PVR was notable for dramatic improvement in all three compared with preoperative values. The degree of improvement in both the PVP group and the TURP group was comparable at all time points of follow-up out to 36 months.


A second randomized clinical trial comparing 120 W PVP with TURP was published in 2011 and provided a 2-year follow-up [5]. Similar IPSS reduction was seen for both PVP and TURP at 2 years (−15.7 and − 14.9, respectively). There was no significant difference in the increase in Qmax between PVP and TURP (+14.5 and + 13.1 mL/s, respectively). Length of hospital stay and time to catheter removal were significantly shorter with PVP.


Similar symptomatic improvement and changes in urodynamic parameters have also been noted in PVP as compared to OP. Alivizatos and colleagues assessed men with prostate glands >80 mL in size who were randomized to either 80 W PVP or transvesical open enucleation at 1 year [3]. All functional parameters improved significantly compared to baseline values in both groups. The IPSS did not differ between the two groups at 3, 6, and 12 months postoperatively. There were no significant differences between the two groups in the Qmax and PVR after surgery. The prostate volume was significantly reduced to a greater degree in the OP group. Another trial evaluating PVP and OP in men with glands >80 mL provided an 18-month follow-up [7]. There was no difference in IPSS between the two groups at 3, 6, 12, and 18 months postoperatively. At 18 months there were no significant differences between the two groups in Qmax and PVR. As seen in the previous study, the prostate volume was lower in the OP group.


A study looking at the efficacy of the GreenLight laser XPS system showed excellent early functional improvement in key parameters up to 6 months following treatment [20]. Mean IPSS scores improved from 19.6 preoperatively to 9.4. Maximum urinary flow rate increased from 8.4 to 21.0 mL/s. There was also a drop in PVR from a mean of 190 mL to a mean of 35 mL. The study was notable for approximately a quarter of the patients having a prostate volume >80 mL. Statistically significant drops in both PSA values and prostate volume at 3 months postoperatively confirm the effectiveness of the XPS system in removing a large amount of prostate tissue.


More recently, the GOLIATH trial enrolled 291 patients at 29 centers in 9 European countries to assess noninferiority of PVP to transurethral resection of the prostate in IPSS at 6 months. A total of 281 patients were ultimately randomized, of which 269 received treatment. Noninferiority was maintained at 12 months [21]. In addition, maximum urinary flow rate, post-void residual urine volume, prostate volume, and prostate-specific antigen were not statistically different between the treatment arms at 12 months [21]. Furthermore, the complication-free rate at 1 year was 84.6% after photoselective vaporization of the prostate vs 80.5% after transurethral resection of the prostate [21].


Two-year results for the GOLIATH trial were published in 2016. Noninferiority in IPSS, maximum flow rate, and reductions in prostate volume and prostate-specific antigen were confirmed again at 24 months [22]. The proportion of patients free of complications through 24 months was 83.6% for photoselective vaporization of the prostate versus 78.9% for transurethral resection of the prostate [22]. This trial demonstrated a durable surgical benefit for photoselective vaporization of the prostate that compares favorably to transurethral resection of the prostate with regards to safety and efficacy.


Photoselective vaporization of the prostate has also been studied in men suffering from urinary retention prior to surgery. Ruszat and colleagues published a subgroup analysis of their results using PVP in men with refractory urinary retention [23]. At 24 months postoperatively, they found a peak urinary flow rate of 19.4 mL/s in men with retention versus 23.3 mL/s in men without retention who has also undergone the procedure. IPSS for the two groups was found to be 4.4 versus 6.5, respectively. Postoperative urinary retention and complication rates were comparable for the two groups. Being in urinary retention also did not have any negative impact on the outcome of 180 W GreenLight laser PVP in the study by Bachmann and associates [20].


There are few studies examining the long-term durability of PVP. Hai reported on the 5-year outcomes on 246 of the first 321 patients who underwent PVP at his institution [24]. The average improvement in AUASS was 79%, while the average improvement in maximal flow rate was 172%. The overall retreatment rate was 8.9%; 19 of the 246 were treated with a repeat PVP due to re-obstruction from prostate adenoma, and 3 underwent transurethral incision of the bladder neck. A study of 500 consecutive patients with mean follow-up of 30 months found a retreatment rate of 6.8% because of insufficient first vaporization or regrowth of prostate tissue [25].


Complications


Complications related to PVP can be categorized as intraoperative, early postoperative, and late. All are relatively infrequent and comparable to those seen in other surgical interventions for BPH.


Intraoperative


Intraoperative bleeding may occur with PVP, but the need for blood transfusion is significantly less likely than what is seen with TURP [2, 26]. In a randomized, prospective trial using the 120 W laser, Al-Ansari et al. reported that 20% of TURPs needed blood transfusions, but none of the PVPs did [2]. In the same study, 16.7% of TURPs had capsular perforated capsule versus none with PVP, and 5% of TURPs had TUR syndrome versus none of PVPs. Even in those patients on anticoagulation, the occurrence of significant intraoperative bleeding is less than TURP [9, 10]. Conversion to TURP because of intraoperative bleeding is a potential adverse event that patients should be warned of prior to PVP. Conversion rates are generally low (<5%) but increase as gland size increases [26].


Other intraoperative complications of endoscopic surgery for BPH to be considered include capsule perforation and TUR syndrome. However, because the irrigating fluid used during PVP is isotonic to saline, the theoretical risk of TUR syndrome should be very low. The GreenLight laser is selective for oxyhemoglobin, and thus minimally vascular tissue such as the fibrotic prostate capsule should be much less susceptible to the effects of the treatment. This reduces the likelihood of capsule perforation compared to the electrocautery of TURP. One study comparing TURP and PVP found a 16.7% capsule perforation rate and 5% risk of TUR syndrome in the patients undergoing TURP with no patient in the PVP group experiencing these complications [2]. Another comparison found a 0.4% versus 6.3% capsular perforated capsule rate between the PVP and TURP groups, respectively [25].


Early Postoperative Complications


Early postoperative complications following PVP include urinary retention, hematuria, dysuria, urinary tract infection, ejaculatory dysfunction, recatheterization, and readmission.


Studies using the 80 W laser report rates of urinary retention ranging from 1% to 15.4%, transient hematuria in 4–18%, transient dysuria in 7–30%, culture-documented UTIs in 6%, and ejaculatory dysfunction (either decreased volume of ejaculate or retrograde ejaculation) ranging from 36% to 55% [19, 2733]. In a large single-center study of 500 patients using the 80 W laser, Ruszat and colleagues reported early postoperative complication rates including hematuria (9.8%), transfusion (0.4%), immediate repeat surgery (0.6%), urosepsis (0.4%), dysuria (14.8%), urge incontinence (2.4%), and UTI (6.8%) [25, 26].


Studies using the 120 W laser report rates of urinary retention at 8%, UTI in 6%, a recatheterization rate of 1–5%, transient hematuria in 12% 120 W 12%, and the need for antimuscarinics to control storage symptoms as being the same as in TURP [5]. In one study using the 120 W laser, the postoperative readmission rate was 6% (3 of 50 patients) including 2 for hematuria and 1 for a febrile UTI [5]. In another study using the 120 W laser, 60 patients (versus 60 TURPs) were followed for a mean of 36 months, and at follow-up, no patient had had clot retention (versus 10% of TURPS); however, 93% reported urgency or dysuria (versus 32% of TURPs) [2].


In a 2010 meta-analysis of published studies on PVP, Ahyai and colleagues found postoperative urinary retention in 9.9%, clot retention in 0%, secondary resection rates of 2.1%, secondary bleeding in 0.7%, urosepsis in 0%, and UTI with fever 12% [34]. Except for clot retention, these numbers were all higher than TURP, bipolar TURP, TUVP, and HoLEP but did not reach statistical significance.


The safety of photoselective vaporization of the prostate remains satisfactory for higher risk patients as well. A multicenter retrospective analysis of 941 men who underwent photoselective vaporization of the prostate specifically assessed the results of high medical risk men [35]. These men were considered high risk if they had an American Society of Anesthesiologists physical status score ≥3. They tended to be older, have larger prostate volumes, and were more likely to be on anticoagulant or antiplatelet medications [35]. At 6 months, the higher medical risk group had similar improvements in IPSS, maximum flow rate, post-void residual urine volume, and reduction in prostate volume as men in the standard risk group, and 90-day complication rates were comparable between the two groups [35]. Of note, the high medical risk group did have more hospital readmissions within 90 days of surgery.


Late Postoperative Complications


Urethral stricture represents one potential late complication from PVP. One study with long-term follow-up found an overall stricture rate of 4.4%, the vast majority of which were in the bulbar urethra (>90%) [25]. The stricture was noted in the first year in 86% of patients with a stricture. This group found that their urethral stricture rate fell significantly after switching from a 26 Fr cystoscope to a 22.5 Fr instrument. In one trial comparing PVP to TURP, urethral stricture was noted in 5.1% of the PVP patients and 8.1% of the TURP patients at 6 months follow-up [6]. These patients did undergo internal urethrotomy as treatment for the stricture. In a study by Alivizatos and associates comparing PVP to OP, only 2 of 65 patients in the PVP group and 1 of 60 patients in the OP group required treatment for urethral stricture [3]. Capitan et al. found that 2 of 50 patients developed urethral meatal stenosis, 6% developed a urethral stricture, 2% had urinary incontinence, and there were no bladder neck contractures [5].


Bladder neck contracture is another potential late complication of PVP. However, much like for urethral stricture, the incidence is generally low. No patient experienced a bladder neck contracture in one comparative study of PVP versus TURP with a 2-year follow-up, while 4% of the TURP patients experienced this complication [5]. In a randomized clinical trial comparing PVP to OP with an 18-month follow-up, 0% versus 3.3% of patients were noted to have bladder neck contractures in the PVP and OP groups, respectively [7].


Patients undergoing PVP should be informed about the possibility of urinary incontinence and erectile dysfunction as part of informed consent of the procedure. The actual incidence of these conditions appears to be quite low in the published literature. In comparison with both OP and TURP, PVP has demonstrated no significant difference in effect on erectile function [3, 4]. Like with TURP, retrograde ejaculation does occur commonly.


Ruszat et al. reported in their single-center study of 500 PVP procedures using the 80 W laser with a 2.5-year mean follow-up of late postoperative complication of bladder neck contracture in 3.6%, urethral stricture in 4.4%, retreatment rates of 6.8%, and incontinence in 1.2% [25]. Using the 120 W laser, Al-Ansari et al. reported in their 60 patients with a mean follow-up of 36 months rates of late complications of needing a redo procedure in 11% and bladder neck contractures in 7.4% [2]. In a meta-analysis by Ahyai et al., rates of late postoperative complications included bladder neck contracture in 5%, urethral stricture in 6.3%, repeat procedure in 5.6%, and dysuria in 8.5% [34].


Special Considerations


Safety of PVP in Men Who Require Continuous Anticoagulation


One of the highly touted advantages of PVP over TURP is that its laser technology allows for a virtually bloodless tissue ablation technique. PVP therefore may be performed safely for patients with medical comorbidities, including a high-risk patient on anticoagulation and antiplatelet therapies [36].


In a two-center study of 66 medically comorbid patients with an ASA score of three or more, Reich et al. reported a 14-point IPSS score reduction and a 222% improvement in Qmax at 1 year, with an 11% recatheterization rate and one patient requiring a redo procedure [29].


In a study of 116 men who underwent PVP while continuing warfarin, aspirin, or clopidogrel therapies, no bleeding complications were observed and no patients required blood transfusions. Of note, these patients did have higher rate of postoperative bladder irrigation (17% versus 5.4% of controls) resulting in longer postoperative catheterization time [9]. These findings have been confirmed in other studies [10, 37].


Safety and Efficacy of PVP in Men with Large Prostates


A number of studies have demonstrated the safety and efficacy of PVP on large prostates. Significant improvements in Qmax and IPSS scores have been reported [30, 38]. However, operating times, the probability of a staged procedure, and the number of laser fibers used to complete the procedure were higher in men with large prostates when compared with smaller prostate glands. Good functional outcomes were maintained, but the incidence of postoperative recatheterization was 5, and 23.1% of patients needed a reoperation within 1 year [30, 38]. These apparent drawbacks of treating large prostates with the early 80 W systems have been minimized with the advent of more powerful (180 W) laser systems.


Another study found a higher safety profile of PVP as compared with TURP [6]. When compared to open prostatectomy for glands >80 mL, PVP patients had longer operating times but shorter catheterization and hospitalization times [3]. Complications and improvements in voiding parameters were similar in both groups. The open prostatectomy group had a higher transfusion rate.


A more recent trial by Meskawi et al. reported on 438 men with prostate volumes greater than 100 mL on transrectal ultrasound who were treated at eight centers in Canada, the United States, and France with photoselective vaporization of the prostate. IPSS, maximum flow rate, and post-void residual urine volume were significantly improved at 6, 12, 24, 36, and 48 months [39]. The median prostate volume for this group of men was 121 mL, and the median prostate-specific antigen value was 6.3 ng/dL. Thirty-seven percent of the men had an indwelling catheter at the time of surgery. Surgical retreatment rates were only 5.4% at 24 months and 9.3% at 36 months [39].


Learning Curve


The learning curve for any surgery plays an important role in its overall acceptance. PVP has been shown to have a shorter learning curve than HoLEP, and this is likely the reason for the greater popularity of PVP [40]. Additionally, some consider PVP to be easier to learn and perform than TURP with reports of urologists feeling comfortable performing TURPs after about 50 procedures [41, 42] and others reporting competence in PVP after performing 10–20 (or fewer) procedures depending on gland size [41]. As with learning any new technique or procedure, the authors advise a mentorship training period to adequately and safely perform PVP.


Cost


An issue worth mentioning is the cost-effectiveness of PVP, as the generator and laser fibers are expensive. A number of studies have examined and summarized the issue of cost of PVP versus TURP [43]. A Swiss study showed similar financial costs for PVP and TURP. OR and postoperative care costs were higher for TURP, while the costs of disposable materials were higher for PVP [44]. Similarly, an Australian study showed that when performed as a same-day surgery procedure and despite the higher cost of equipment and disposables, PVP was less expensive than TURP. Cost savings with PVP generally were due to shorter hospital stays, shorter catheterization times, and lower complication rates [4].


A 2006 study examined the clinical outcomes and cost characteristics of PVP, TUMT, TUNA, interstitial laser coagulation, and TURP using a decision analytic Markov model. In this model, PVP resulted in the largest beneficial changes in IPSS, Qmax, and QoL scores, and the expected cost per patient at all time points was lowest for PVP. The cost savings of PVP was due to lower rates of adverse events and retreatments [45].


It is important to keep in mind that the cost-effectiveness of any treatment depends on the different reimbursement systems in different countries. Therefore, it is difficult to draw general conclusions that are applicable to every country or health-care delivery system.


Conclusions


PVP is one of a number of laser technologies available for the treatment of lower urinary tract symptoms due to benign prostatic obstruction. This treatment carries with it a quick learning curve, a low risk of bleeding, the ability to perform the surgery if men are unable to stop blood-thinning agents, a short postoperative catheterization, and a short hospital stay. However, the equipment is expensive, and there are increased retreatment and dysuria rates as compared to TURP. Urologists need to be aware of the advantages and disadvantages of not only PVP but of the array of technologies available for the surgical treatment of LUTS due to BPH. Ultimately, urologists needs to know and review their own outcomes with benign prostate surgeries and offer their patients the treatments that in their own hands have the best outcomes and fewest complications, particularly in the era of cost-conscious and evidence-based medicine.

Oct 20, 2020 | Posted by in UROLOGY | Comments Off on Vaporization of the Prostate

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