Efficacy and Safety of Plasmakinetic Resection of the Prostate in Patients with a Prostate Gland Larger than 80 cc: 30-Month Follow-Up Results

Abstract

Purpose:

This study aimed to evaluate the efficacy and safety of transurethral plasmakinetic resection of the prostate (PKRP) for the treatment of patients with benign prostatic hyperplasia (BPH) in men with prostate volume >80 cc.

Patients and Methods:

From January 2010 to December 2011, 120 patients were included in our study; among these patients, 66 had prostate sizes of 80 cc to 100 cc and 54 had prostate sizes >100 cc. Pre-, peri- and postoperative evaluations were performed.

Results:

The mean operative duration of PKRP was 112 minutes, and the mean resected tissue weight was 60.01 g. Hemoglobin level decreased by 0.65±0.52 g/dL, and serum sodium content decreased by 0.06±2.62 mmol/L. The mean catheterization time was 83.05 hours, and the mean hospital stay was 12.47 days. The short follow-up time (30 months) demonstrated significant improvement in International Prostate Symptom Score, quality of life, and postvoid residual volume compared with preoperative characteristics. One patient underwent reoperation because of a blood clot in the bladder. Twelve patients complained of retrograde ejaculation. No patient experienced urinary incontinence.

Conclusions:

PKRP is safe and efficacious for men with BPH who have a large prostate (volume >80 cc).

Introduction

Lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH) are often bothersome and interfere with the quality of life (QoL) of middle-aged or elderly men.¹ Because not all patients with LUTS will choose to seek medical guidance, the prevalence of LUTS may be underestimated and could include approximately 25% of men who are aged ≥50 years. The prevalence of BPH, particularly histologic BPH, which has been examined in several autopsy studies worldwide, accounts for approximately 40% of men in their 50s and even reaches 90% of men in their 90s.

LUTS caused by BPH can cause severe economic burden to the society. For instance, in America, the treatment for this condition costs more than $2 billion every year. At present, the recommended treatment for BPH includes intense monitoring of behavior, drug treatment, and surgical treatment. Drug treatment can alleviate LUTS and improve QoL to a certain degree.² Surgical management is still necessary, however, because drug treatment can be ineffective in some patients.

With the application of minimally invasive endoscopy, transurethral resection of the prostate (TURP) is a monopolar electrosurgical technology considered as the golden standard to surgically manage LUTS secondary to BPH.³ In this treatment option, an electrical loop is inserted through the patient's body by using mannitol as the flushing fluid. According to the European Association of Urology (EAU) Guidelines 2012, monopolar TURP is the preferred management option for prostates with a volume of 30 cc to 80 cc. With the advancement of drug treatments, an increase in the size of prostate gland will improve along with the associated complications of TURP, including bleeding, sepsis, and transurethral resection (TUR) syndrome, because of fluid absorption.^4,5

Bipolar electrosurgical technology has been widely recommended and used worldwide currently, aiming to decrease the complications and maintaining efficacy of the standard monopolar TURP; many similar devices have been developed by different companies.^6,7 The development of the PlasmaKinetic Tissue Management System (Gyrus Medical Ltd., Bucks, UK) has been demonstrated as effective as TURP for BPH because it provides good long-term results and results in fewer early complications.^8,9 Recent studies, however, on plasmakinetic resection of the prostate (PKRP) have been performed on patients with small to medium prostate gland sizes.^10
–12 The efficacy of PKRP should be assessed in patients with large prostates.

This investigation is a retrospective study and included patients with prostate glands >80 cc who were undergoing PKRP in our hospital. The present study was conducted to evaluate the clinical efficacy and safety of PKRP in patients with large prostates.

Patients and Methods

Study design

This investigation is a retrospective study and included patients with large prostate glands (>80 cc) who were undergoing PKRP in our hospital from January 2010 to December 2011. The inclusion criteria were as follows: Patients with LUTS after therapy with medical treatment and required surgery failed; prostate volume (measured using transrectal ultrasonography [TRUS]) >80 cc; and with a postoperative pathologic diagnosis of BPH. Exclusion criteria were listed as follows: Bladder stone, neurogenic bladder, prostatic cancer, urethral stricture, and history of prostate surgery.

The standard investigative protocol included the preoperative information (age, prostate size, free prostate-specific antigen [PSA], International Prostate Symptom Score [IPSS], quality of life [QoL], maximum flow rate [Qmax], and postvoid residual [PVR] volume) and perioperative information (operative duration, resected tissue weight, hemoglobin decrease, catheterization time, hospital stay, reoperation rate, transfusion rate, and TUR syndrome rate). We followed up patients by evaluating IPSS, QoL, Qmax, PVR volume, and complications.

Preoperative preparation

A routine preoperative examination, including TRUS, digital rectal examination, PVR volume, uroflowmetry, and functional bladder capacity measurement, was conducted for all the patients. Moreover, all of the patients answered the IPSS and QoL questions. Patients with acute urinary retention were catheterized, and antibiotics were administered for urinary tract infection. Patients with hypertension were given antihypertensive treatment, and patients with coronary heart disease were provided with treatment for blood vessel expansion. Fasting blood glucose levels were controlled at 8.0 mmol/L for patients with diabetes.

Equipment

The PK system consisted of a PK Generator (the capability is 200 W, the radiofrequency ranges from 320 kHz to 450 kHz, and the voltage ranges from 350 V to 450 V) and a PK Super-Loop Electrode. This system can automatically preprogram 160 W for cutting and 80 W for coagulation after power on; of course, the automatically settings can be changed by the physician at any time. The flushing fluid was saline.

Surgical procedures

According to the actual situation, we chose the best surgical technique, specific as follows:

1) Divided anterograde resection—prostate size >80 to 100 cc, the adenoma and surgical capsule were adhered tightly. Incisions deep into the plane of the surgical capsule of prostate were made at the 12-o'clock position and the conjuction of the lateral lobes and the middle lobe. Then the divided lateral lobes and middle lobe were resected anterogradely.

2) Divided retrograde resection—prostate size >80 to 100 cc, the adenoma could be easily separated from the surgical capsule. A circular groove to the surgical capsule at the proximal part of the verumontanum and the distal edge of the prostate lobes was made by incising with the cutting loop and pushing with the tip of the resectoscope. Incisions deep into the plane of the surgical capsule of prostate were made at the 12-o'clock position and the conjuction of the lateral lobes and the median lobe. The adenoma was separated by the push of the resectoscope sheath, like the procedure used to remove the proliferated prostate with a finger in a suprapubic transvesical prostatectomy. At last the separated lateral lobes and middle lobe were removed by the cutting loop.

3) Undivided retrograde enucleation—prostate size >80 cc, the adenoma could be easily separated from the surgical capsule. A circular groove to the surgical capsule at the proximal part of the verumontanum and the distal edge of the prostate lobes was made by incising with the cutting loop and pushing with the tip of the resectoscope. The whole adenoma was separated by the push of the resectoscope sheath, only attached to the bladder neck in the 4-o'clock and 8-o'clock positions. At last, the separated adenoma was resected by the cutting loop.

Statistical analysis

Statistical analysis was performed using Student t test, Mann-Whitney test, and chi-square test. P<0.05 was considered statistically significant. Statistical data were presented as mean±standard deviation (SD).

Results

A total of 120 patients were included in our study, among whom 66 patients had prostate sizes of 80 cc to 100 cc and 54 patients had a prostate size >100 cc. Table 1 shows the baseline characteristics of the selected patients.

Table 1.

Baseline Patient Characteristics

	Mean±SD
Age (y)	72.3±6.65
Prostate size (mL)	101.05±18.78
Total PSA (ng/mL)	2.94±1.31
fPSA/tPSA	0.556±0.082
Preoperative hemoglobin (g/dL)	13.65±1.24
Preoperative serum sodium (mmol/L)	141.34±2.62
IPSS	19.97±7.12
QoL	5.6±0.9
Qmax (mL/s)	7.25±2.62
PVR (mL)	131.08±139.63

SD=standard deviation; PSA=prostate-specific antigen; fPSA=free prostate-speific antigen; tPSA=total prostate-specific antigen; IPSS=International Prostate Symptom Score; QoL=quality of life; Qmax=maximum flow rate; PVR=postvoid residual.

The mean operative duration of PKRP was 112±40.62 minutes (ranging from 30 min to 210 min); however, the mean resected tissue weight was 60.01±17.02 g (range 32 g to 101 g). Hemoglobin level decreased by 0.65±0.52 g/dL whereas serum sodium content decreased by 0.06±2.62 mmol/L. The mean catheterization time was 83.05±36.09 hours (range 24 h to 231 h), and the mean hospital stay was 12.47±4.46 d (range 6 d to 23 d). These results are summarized in Table 2.

Table 2.

Perioperative Data

	Mean±SD
Operative duration (min)	112±40.62
Resected tissue weight (g)	60.01±17.02
Postoperative hemoglobin decrease (g/dL)^a	0.65±0.52
Postoperative serum sodium decrease (mmol/L)	0.06±2.62
Catheterization time (h)	83.05±36.09
Hospital stay (d)	12.47±8.46
Reoperation	1
Transfusion	2
TUR syndrome	0

Values assayed at the beginning of operation and 1 hour postoperatively.

TUR=transurethral resection.

Table 3 presents the complete urinary function follow-up data. At 30 months of the follow-up period, significant improvements in IPSS, QoL, PVR, and Qmax were noted. One patient underwent reoperation because of a blood clot in the bladder. Twelve patients complained of retrograde ejaculation. No patient experienced urinary incontinence.

Table 3.

Intention-to-Treat Analysis of Follow-Up Data

Parameters	Overall	Prostate size ≥80<100 cc	Prostate size ≥100 cc	P-value
IPSS
Baseline	19.97±7.12	18.70±4.12	21.10±5.77	0.009
6 months	4.84±2.05^a	4.68±1.69	5.02±2.31	0.354
12 months	5.51±3.15^a	5.16±2.94	5.63±2.58	0.359
24 months	5.56±1.86^a	5.24±2.23	5.78±1.98	0.168
30 months	5.60±2.44^a	5.30±1.77	5.90±2.61	0.138
QoL
Baseline	5.60±0.90	5.41±0.78	5.72±0.62	0.019
6 months	2.55±0.56^a	2.35±0.76	2.76±1.44	0.048
12 months	1.61±0.82^a	1.50±0.91	1.78±0.96	0.105
24 months	1.20±0.73^a	1.14±0.55	1.32±0.61	0.092
30 months	1.22±0.50^a	1.13±0.23	1.28±0.68	0.096
Qmax(mL/s)
Baseline	7.25±2.62	7.89±3.07	7.01±3.16	0.126
6 months	25.12±12.30^a	25.60±10.25	25.06±11.21	0.784
12 months	21.70±6.21^a	21.98±4.58	20.34±5.84	0.087
24 months	21.35±8.45^a	21.55±7.25	21.20±7.88	0.801
30 months	20.05±10.49^a	20.73±5.64	19.98±9.24	0.586
PVR (mL)
Baseline	131.08±39.63	122.52±34.16	138±42.53	0.029
6 months	25.69±10.25^a	22.89±9.35	26.14±8.96	0.056
12 months	22.84±7.63^a	20.76±8.55	24.10±10.23	0.054
24 months	28.35±11.56^a	26.62±7.38	28.77±10.46	0.190
30 months	29.74±12.11^a	27.97±9.92	31.20±13.42	0.133

P<0.001 compared with baseline.

Discussion

BPH associated with LUTS is a common and often bothersome condition in aging men.¹³ It is a histologic diagnosis characterized by epithelial cell and smooth muscle proliferation in the prostatic transition zone leading to nonmalignant prostate enlargement and bladder outlet obstruction.

The current gold standard surgical treatment for patients with BPH is still TURP. The EAU Guidelines 2012 suggested that monopolar TURP is the treatment of choice for prostates of 30 cc to 80 cc, while the surgical management recommended for prostate of >80 cc was open prostatectomy. Open surgery, however, can cause serious injury to patients, and current minimally invasive surgical techniques are bipolar TURP and laser treatment. Laser treatment is costly and necessitates a long training curve for physicians.

We recommend the application of the PK system to manage large prostates of >80 cc. In addition, most of patients with larger prostates were old/aging. Considering this problem, open prostatectomy may be more invasive and lead to more rehabilitation difficulties for older patients. Thus, PKRP may have superior efficacy on this aspect and be more suitable for older patients.

In the present study, the PK system produced by Gyrus was used. Compared with monopolar TURP, the bipolar TURP uses a specialized resectoscope loop (it is made up of active and return electrodes, which can ensure electrosurgical tissue cutting in a conductive saline medium). When high-frequency current is activated, the physiologic saline surrounding the loop is heated until reached the boiling point. A high electrical resistance environment is created by the bubbles, and the voltage between electrode and saline solution spikes to form an arc. The heat of the arc ignition indirectly heats the tissue, thereby enabling both resection and coagulation.^8,14

In the present study, two patients needed transfusion; one patient needed transfusion because of halfway coagulation leading to a blood clot in the bladder and the other patient needed transfusion because of a large prostate (211 cc) and long operative duration. PKRP cuts tissue in a saline medium and can reduce the TUR syndrome.

In the present study, no patient experienced TUR syndrome. The PK system can decrease peri- and postoperative bleeding, thereby improving the operation view and shorten the rehabilitation duration of patients. Moreover, a clear operation view can help protect the urethral sphincter and the verumontanum. In the present study, the mean operative duration was 112±40.62 minutes, and the mean resected tissue weight was 60.01±17.02 g. PKRP is better for coagulation; as such, the mean catheterization time was 83.05±36.09 hours, and hospital stay time was 12.47±4.46 days, indicating a faster rehabilitation. In addition, the IPSS and Qol of patients were improved compared with baseline.

To our knowledge, no study has reported the influence of PKRP on the sexual function of patients, but studies on the comparison of other bipolar systems (Olympus and VISTA) and monopolar TURP have shown that no significant difference was found between the effects of bipolar and monopolar TURP on sexual function.¹⁵ In our study, 12 (10%) patients and 7 patients complained of retrograde ejaculation. The main complication of PKRP on sexual function of patients with BPH was retrograde ejaculation, rather than erectile dysfunction.

In the present study, we investigated the short-term efficacy of PKRP for large prostate glands; however, its long-term efficacy still needs to be assessed. Moreover, multiple centers and controlled studies on the efficacy of PKRP for large prostate glands are needed.

Conclusion

The efficacy and safety of PKRP on BPH patients with prostates >80 cc were investigated. Our study provided the basis of PKRP that could be promoted and applied.

Footnotes

Acknowledgments

This study was supported by the National Natural Science Foundation of China (No. 81202027) and Independent Research Projects of Wuhan University (No. 111086).

Disclosure Statement

No competing financial interests exist.

Abbreviations Used

References

, Zeng

, Ruan

, et al. Simultaneous transurethral resection of bladder cancer and prostate may reduce recurrence rates: A systematic review and meta-analysis. Exp Ther Med, 2012; 4:685–692.

Wang

, Wang

, Li

, et al. Comparative effectiveness of oral drug therapies for lower urinary tract symptoms due to benign prostatic hyperplasia: A systematic review and network meta-analysis. PLoS One, 2014; 9:e107593.

, Zeng

, Ruan

, et al. Holmium laser enucleation versus transurethral resection in patients with benign prostate hyperplasia: An updated systematic review with meta-analysis and trial sequential analysis. PLoS One, 2014; 9:e101615.

Akcayoz

, Kaygisiz

, Akdemir

, et al. Comparison of transurethral resection and plasmakinetic transurethral resection applications with regard to fluid absorption amounts in benign prostate hyperplasia. Urol Int, 2006; 77:143–147.

Galanakis

, Celia

, Del Biondo

, et al. Evolving transurethral resection of the prostate: Enucleation-resection of the prostate. J Endourol, 2010; 24:2043–2046.

, Wang

, Wu

, Wang

. Use of bipolar energy for transurethral resection of superficial bladder tumors: Long-term results. J Endourol, 2008; 22:545–549.

Fagerstrom

, Nyman

, Hahn

. Complications and clinical outcome 18 months after bipolar and monopolar transurethral resection of the prostate. J Endourol, 2011; 25:1043–1049.

Kong

, Ibrahim

, Zainuddin

. A prospective, randomized clinical trial comparing bipolar plasma kinetic resection of the prostate versus conventional monopolar transurethral resection of the prostate in the treatment of benign prostatic hyperplasia. Ann Saudi Med, 2009; 29:429–432.

Nuhoglu

, Ayyildiz

, Karaguzel

, et al. Plasmakinetic prostate resection in the treatment of benign prostate hyperplasia: Results of 1-year follow up. Int J Urol, 2006; 13:21–24.

10.

de Sio

, Autorino

, Quarto

, et al. Gyrus bipolar versus standard monopolar transurethral resection of the prostate: A randomized prospective trial. Urology, 2006; 67:69–72.

11.

Patankar

, Jamkar

, Dobhada

, Gorde

. PlasmaKinetic Superpulse transurethral resection versus conventional transurethral resection of prostate. J Endourol, 2006; 20:215–219.

12.

Yoon

, Kim

, Moon

, et al. Transurethral resection of the prostate with a bipolar tissue management system compared to conventional monopolar resectoscope: One-year outcome. Yonsei Med J, 2006; 47:715–720.

13.

Zeng

, Yao

, Weng

, et al. Meta-analysis of vitamin D receptor gene polymorphisms and benign prostatic hyperplasia risk. Mol Biol Rep, 2014; 41:6713–6717.

14.

Yang

, Lin

, Chang

, et al. Gyrus plasmasect: Is it better than monopolar transurethral resection of prostate?. Urol Int, 2004; 73:258–261.

15.

Mamoulakis

, Skolarikos

, Schulze

, et al. Bipolar vs monopolar transurethral resection of the prostate: Evaluation of the impact on overall sexual function in an international randomized controlled trial setting. BJU Int, 2013; 112:109–120.