Can transurethral thermotherapy save elderly patients with benign prostatic obstruction and high ASA score?

Abstract

Introduction

The Aim of this study was to investigate the efficacy of the new bipolar radiofrequency prostate thermotherapy method for those with high potential surgical risk and also for patients with a chronic catheter.

Material and Methods

103 patients attending our clinic due to BPO and related complaints with high ASA score had outcomes after the procedure recorded prospectively and investigated retrospectively. Qmax, prostate volume, IPSS score, quality of life score, and presence of catheters were recorded before the procedure and analyzed with the outcomes after the procedure.

Results

The ASA scores were calculated as 3.0 ± 1.0 (IQR). Before the procedure, Qmax values (mean (SD)) were 5.11 ± 5.37 ml/s, while in the 6th month after the procedure Qmax values were identified as 10.45 ± 3.8 ml/s (p < 0.001). Of 53 patients (55.2%) with chronic catheters who could not be operated, 30 (61.2%) no longer required urinary catheter.

Conclusion

Bipolar RF thermotherapy appears to be an effective method for patients with BPO who cannot be operated. Due to the surgical risks of patients dependent on the catheter in spite of receiving medical treatment, it is a good alternative to remove catheter dependence. It may be one of the methods that should be remembered, especially in this patient group.

Keywords:

• Benign prostatic obstruction
• treatment
• thermotherapy
• radiofrequency
• complication

Introduction

Benign prostatic obstruction (BPO) is one of the uropathologies most frequently seen in men over the age of 40. Generally known to be observed in later years, BPO is rarely observed before the age of 40 and is observed at rates of 30–40% from 50 to 55 years with this rate reaching very high rates of 80–90% by 80 years or older [1]. Especially in patients with advanced age, it is shown to be an important cause of disrupted quality of life. In this patient group, BPO or linked lower urinary tract symptoms are frequently observed in addition to complications like renal failure, infectious situations, and falls linked to nocturia and increase the need for treatment [2].

According to the latest American Urological Association (AUA) guidelines for patients requiring surgical treatment for BPO, transurethral resection of the prostate (TUR-P) is still presented as the first method [3]. However, in some of this patient group surgical treatment cannot be performed due to high anesthesia risks linked to cardiac, respiratory, and neurologic problems [4]. Additionally, some people must live with a catheter due to these reasons and reject surgical treatment due to potential complications.

In recent years, nonsurgical or minimally invasive methods have come to the agenda to reduce complication rates for BPO treatment. The transurethral bipolar radiofrequency (RF) thermotherapy method is presented as an alternative technique to transurethral resection and has gained importance in daily practice. Due to being nonsurgical, not requiring anesthesia, being an outpatient method, and being easy to perform, it is a choice for BPO treatment with increasing use [5].

When the literature is examined, there is insufficient data about the surgical outcomes of patients with high risk. This study aims to investigate the efficacy of the RF thermotherapy method in patients who cannot have surgical treatment due to high anesthesia risk in terms of Qmax values and endindg permanent catheter dependence.

Material and method

This study was performed in the urology clinic of Ordu University. From April 2017 to December 2019, the outcomes for patients with transurethral bipolar radiofrequency thermotherapy performed were recorded prospectively and reviewed retrospectively. Patient measurements and records were taken by a single doctor. Patients with obstructive lower urinary tract complaints resistant to medical treatment and requiring prostate surgery had uroflowmetry tests, prostate volume, post-voiding residual urine (PVR) amounts and international prostate symptom scores (IPSS) investigated and recorded before the procedure. Patients with maximum urine flow rate (Qmax) below 10 ml/s, with prostate volume from 30–100 ml and with prostatic urethra length (from bladder neck to verumontanum) less than 50 mm were included in the study. Patients with obstructive complaints resistant to medical treatment and requiring surgery and patients using clean interval catheterization or urinary catheter due to urinary retention without neurologic infrastructure had the catheters removed under medical treatment compression to observe whether urination occurred and prostate volumes recorded. All patients had the American Society of Anesthesiologists (ASA) scores calculated. Patients with ASA values of III and above with high complication rates for anesthesia and surgery were included in the study. Patients were treated with a TEMPRO direx transurethral thermotherapy radiofrequency ablation system. Before the procedure patients had a silicon-coated catheter with 16 Fr (5.5 mm) diameter inserted into the urethra under local anesthesia and an applicator with 3 different sensors for different regions of the prostate was inserted. Patients had transurethral bipolar radiofrequency ablation treatment applied with the middle model gradient method at 55 °C for 1 h. After the procedure, patients had a Foley catheter inserted for 7 days. Patients had Qmax values, prostate volume, PVR values and IPSS scores measured again at the end of the 1st and 6th months and these were retrospectively investigated.

The IPSS is a current survey form investigating lower urinary tract complaints of patients with 7 questions. It is a rapid and validated test for questioning obstructive status like difficulty urinating, lack of full voiding of urine, need to urinate in periods shorter than 2 h, and intermittent urination, along with a quality of life index.

The study did not include patients with active urinary tract infection, high prostatic median lobe, previous radiotherapy to the pelvic region, or considered to have neurogenic-sourced bladder dysfunction. Patients with pacemakers consulted with cardiology and had the procedure performed after stopping the pacemaker and then the pacemaker was reset.

Statistics

Statistical analyses were performed with SPSS 21.0 (IBM, Chicago, IL). To determine the fit of variables to a normal distribution, one simple Kolmogorov–Smirnov test was used. Variables with normal distribution are shown as mean ± standard deviation, while variables without normal distribution are shown as median ± interquartile range. Statistical analysis used the paired t-test and Wilcoxon signed-rank test. A p-value <0.05 was accepted as statistically significant.

Results

A total of 103 patients had the bipolar radiofrequency thermotherapy procedure performed. The mean age of patients was 75.35 ± 11.15, and mean body mass index was 25.27 ± 3.99 kg/m². Of patients, 36.5% had at least 1 and 42.7% had 2 systemic diseases. Systemic diseases and incidences are summarized in Table 1.

Table 1. Systemic diseases and distribution.

	n	%
Systemic diseases
Diabetes Mellitus	22	21.4
Asthma, COPD	23	22.3
Hypertension	34	33.0
Heart failure	27	26.2
Psychiatric	3	2.9
Coexistence of comorbidities
1	35	36.5
2	41	42.7
3	18	18.8
4	2	2.1

The median ASA score for patients was 3.0 ± 1.0 (IQR) and 10 patients (9%) died during the follow-up due to systemic diseases. These patients did not encounter any problem during the procedure; however, patients who died could not complete the 6-month surveillance process. As a result, the study had to be completed with a total of 93 patients in the 6th month.

When patients first attended the clinic, 72.8% were using medication. The medications and incidences used for lower urinary tract complaints before the procedure are summarized in Table 2. In 53 patients (55.2%) catheter was inserted due to urinary retention. Then the medical treatment was begun and catheters were removed during check-ups for reassessment. If urinary retention or the inability to urinate was present during the assessment, the catheter was reinserted. These patients had RF thermotherapy applied due to high surgical risks and ASA scores.

Table 2. Medications and distribution on admission.

Medical treatment	n	%
Alpha blocker	24	23.3
5 ARI	11	10.7
Anticholinergic	9	8.7
Total	44	42.7

The Qmax values for patients were measured before the procedure and in the 1st, 3rd, and 6th month after the procedure. Before the procedure, mean Qmax value (mean (SD)) was 5.11 ± 5.37 ml/s while in the 1st month after the procedure Qmax was identified as 8.91 ± 5.16 ml/s (p < 0.001). Mean Qmax value in the 3rd month after the procedure was 10.51 ± 3.88 ml/s (p < 0.001), and in the 6th month it was 10.45 ± 3.8 ml/s (p < 0.001). When the Qmax values after the procedure are compared, the 1st- and 6th-month values did not appear to have significant Qmax value loss (p = 0.056). The mean prostate volume was 46.99 ± 24.22 ml before the procedure while after the procedure it was 45.96 ± 22.76 ml and no statistically significant variation was observed (p = 0.626; Table 3). Of the 53 patients (55.2%) with a urinary catheter inserted, 30 (61.2%) did not require a urinary catheter after the procedure and their dependence on the catheter was resolved.

Table 3. Qmax and prostate volume before and after procedure.

	Mean ± SD	p
Qmax
Before	5.115 ± 5.4	0.000***
1st month	8.913 ± 5.2
Before	5.980 ± 6.2	0.000***
3rd month	10.515 ± 3.9
Before	5.980 ± 6.2	0.000***
6th month	10.456 ± 3.8
1st month	9.327 ± 4.1	0.056
6th month	10.456 ± 3.8
P. vol.
Before	46.992 ± 24.2	0.626
After	45.962 ± 22.8

*p < 0.05; ***p < 0.001. P. vol.: Prostate volume.

Table 4. IPSS and QoL scores before and after procedure.

	Median ± IQR	p
IPSS
Before	21.0 ± 16	0.002**
6th month	16.0 ± 9
QoL
Before	3.5 ± 1	0.014*
6th month	3.0 ± 1

*p < 0.05; **p < 0.01.

The mean IPSS score (median (IQR)) recorded before the procedure was 21.0 ± 16, while the IPSS score in the 6th month was 16.0 ± 9 with a statistically significant reduction in symptoms observed (p = 0.002, Table 4). Before the procedure mean quality of life (QoL) score was 3.6 ± 1 while in the 6th month after the procedure, QoL was 3 ± 1 (p = 0.014).

Discussion

BPO is currently a commonly observed significant health problem with the incidence increasing with age. It may affect the quality of life significantly especially in the elderly patient group. As in our patient group, the presence of advanced age along with comorbid diseases may cause serious surgical complication risks in patients [6]. During our follow-up, 10 patients died due to different causes, and additionally, 42% of patients had at least 2 systemic diseases which is an important marker of this situation. However, though in the advanced age group, patients generally do not choose to use a urinary catheter due to BPO and wish to take their chance with surgical intervention. When the transurethral radiofrequency method is applied to this patient group, significant improvement was provided when Qmax values before the procedure are compared to those in the 1st and 6th month (p < 0.001). When results from the 1st and 6th months are compared, this effect was permanent and there was no significant difference between the results (p = 0.056). These results are followed by patients’ symptom scores. Before the procedure the IPSS total score was mean 21.0 ± 16 (IQR), while the IPSS score in the 6th month was 16.0 ± 9 and a significant improvement was observed in scores. The quality of life index for patients in the 6th month was 3 ± 1 and the increase in quality of life was statistically significant.

Though the basic effect of RF thermotherapy method for BPO treatment begins later, it is shown to be an alternative to pharmacologic treatment due to more permanent and lower side effect rates [7]. Especially in the patient group with surgical risk and high ASA score, it is a procedure that is reliable, can be performed under clinical conditions, and does not require anesthesia. As a result, it may be shown to be an alternative to TUR-P for patients with high surgical risk [7]. It may be considered a choice for patients who have advanced age, who cannot be operated and who are dependent on a urinary catheter. In patients with advanced age, the age factor alone increases the risk of patients requiring a urinary catheter [8]. In our patient group, 53 patients who could not have anesthesia had a chronic catheter due to urinary retention and RF thermotherapy had a 61.2% success rate with catheter-dependence resolved in these patients. It should be considered an important treatment choice, especially for this patient group.

RF thermotherapy theoretically causes rapid vascular thrombosis and then more pronounced clotting necrosis [9]. This effect is greater no matter how small the prostate tissue is which is one of the reasons for individual differences after the procedure. The prostate composition appears to be effective in predicting success after the procedure. When it is considered that LUTS complaints may be due to the median lobe, as they are due to asymmetric prostate growth, it is considered these patients will not benefit from the RF ablation procedure [10]. In our study, patients with median lobe identified were excluded from the study. The denervation effect of RF ablation contributes to the effect of coagulation necrosis. Along with coagulation necrosis induced in deep prostate tissues, denervation and axon loss is thought to affect muscle tissue. Denervation developing in neurons is estimated to occur as a result of angiopathy and protein denaturation due to heat forming during the procedure. In this way, though there is no clear change in the prostate volume, this explains how better uroflowmetry values are formed even with similar volumes after the procedure [11]. In our study, though there was no clear difference in prostate volumes measured before and after the procedure (p = 0.626), the provision of a significant improvement in Qmax values is thought to have occurred due to the development of denervation (p < 0.001).

A study by Sugiyama et al. explained better levels of urination without resecting adenoma tissue with similar volumes with isometric spasm studies. The study showed that nerve fibers are more sensitive to heat compared to smooth muscle and that irreversible nerve damage occurs over 48 °C. In this way, the sympathetic system is blocked by preventing autonomic suppression affecting smooth muscle and prostatic urinary canal and pathologic investigations observed a larger scale of nerve damage than muscle damage [12]. These findings explain how RF thermotherapy has similar effects on alpha blockers and local anesthetics. In this way, it is considered that RF thermotherapy may be beneficial for cases like chronic prostatitis due to the reduction in subjective irritative symptoms in BPO due to damage to urethral afferent nerves [13].

When outcomes are examined economically, the use of thermotherapy methods was shown to have potential savings in terms of cost. Lower costs are provided by outpatient administration removing steps like admitting patients and follow-up procedures [14]. A cohort study comparing the cost of thermotherapies with both TUR-P and alpha-blockers found 5-year highest economic benefit was observed in the thermotherapy group compared to the other two groups [15].

There are some limitations to this study. The study included a single-center and no control group was used. Patients were evaluated for short-term 6-month outcomes. There is a need for expanded and long-term studies to observe the long-term effect of RF thermotherapy in patients with a high ASA score.

Conclusion

The results of this study show that bipolar RF prostate ablation treatment for patients who cannot have surgical treatment due to high anesthesia risk provided significant improvement in Qmax values and in reducing dependence on urinary catheters. As a result, we think this is an effective treatment method that can be offered to patients without the chance of surgical treatment or who wish to avoid potential complications of surgical treatment. Additionally, this treatment has significant advantages of being an outpatient, daytime, and comfortable procedure that can be repeated when required.

Disclosure statement

No potential conflict of interest was reported by the author(s).