Does transurethral microwave thermotherapy (TUMT) improve bothersome urinary symptoms without unwanted side effects in men with an enlarged prostate?
An enlarged prostate may cause bothersome urinary tract symptoms, such as having to urinate often during the day or night, having a weak stream, and the feeling of not completely emptying the bladder. When lifestyle changes (like drinking fewer liquids) or medications do not help, men may choose to have surgery, such as transurethral resection of the prostate. However, this procedure may cause unwanted effects, such as erection and ejaculation problems, or require retreatment. This review looks at the results of transurethral microwave thermotherapy, which is an alternative, less invasive procedure that uses microwave energy to reduce prostatic tissue.
We found no study comparing transurethral microwave thermotherapy with the other newer and less invasive treatments for this condition.
We found 16 studies with 1919 men that compared transurethral microwave thermotherapy with a simulated procedure (participants are made to believe they received treatment, while in reality, they did not) or with traditional surgery (transurethral resection of the prostate (TURP)). Participants’ average age was 69 years, and most had a moderate degree of bothersome urinary symptoms.
Compared to the traditional surgery (TURP), transurethral microwave thermotherapy probably results in little to no difference in urinary symptoms at short-term follow-up, but we are uncertain about its long-term effects. There may be little to no difference in quality of life or problems with erections between these interventions both short-term and long-term. This procedure likely results in fewer serious side effects and problems with ejaculation compared to surgery. However, it likely results in an increase in the need for retreatment (including surgery).
Compared to a simulated procedure, transurethral microwave thermotherapy probably improves urinary symptoms and the need for retreatment at short-term follow-up (less than 12 months). This treatment may make little to no difference in the quality of life. We are very uncertain whether or not serious unwanted side effects, including problems with erection and ejaculation, are more common.
Findings of this review are up-to-date until 31 May 2021.
Certainty of the evidence
The certainty of the evidence for the outcomes ranged mostly from moderate to low due to shortcomings in how the studies were conducted and small study size. This means that we have either moderate or limited confidence in the results.
TUMT provides a similar reduction in urinary symptoms compared to the standard treatment (TURP), with fewer major adverse events and fewer cases of ejaculatory dysfunction at short-term follow-up. However, TUMT probably results in a large increase in retreatment rates. Study limitations and imprecision reduced the confidence we can place in these results. Furthermore, most studies were performed over 20 years ago. Given the emergence of newer minimally-invasive treatments, high-quality head-to-head trials with longer follow-up are needed to clarify their relative effectiveness. Patients' values and preferences, their comorbidities and the effects of other available minimally-invasive procedures, among other factors, can guide clinicians when choosing the optimal treatment for this condition.
Transurethral resection of the prostate (TURP) has been the gold-standard treatment for alleviating urinary symptoms and improving urinary flow in men with symptomatic benign prostatic hyperplasia (BPH). However, the morbidity of TURP approaches 20%, and less invasive techniques have been developed for treating BPH. Transurethral microwave thermotherapy (TUMT) is an alternative, minimally-invasive treatment that delivers microwave energy to produce coagulation necrosis in prostatic tissue. This is an update of a review last published in 2012.
To assess the effects of transurethral microwave thermotherapy for the treatment of lower urinary tract symptoms in men with benign prostatic hyperplasia.
We performed a comprehensive search using multiple databases (the Cochrane Library, MEDLINE, Embase, Scopus, Web of Science, and LILACS), trials registries, other sources of grey literature, and conference proceedings published up to 31 May 2021, with no restrictions by language or publication status.
We included parallel-group randomized controlled trials (RCTs) and cluster-RCTs of participants with BPH who underwent TUMT.
Two review authors independently assessed studies for inclusion at each stage and undertook data extraction and risk of bias and GRADE assessments of the certainty of the evidence (CoE). We considered review outcomes measured up to 12 months after randomization as short-term and beyond 12 months as long-term. Our main outcomes included: urologic symptoms scores, quality of life, major adverse events, retreatment, and ejaculatory and erectile function.
In this update, we identified no new RCTs, but we included data from studies excluded in the previous version of this review. We included 16 trials with 1919 participants, with a median age of 69 and moderate lower urinary tract symptoms. The certainty of the evidence for most comparisons was moderate-to-low, due to an overall high risk of bias across studies and imprecision (few participants and events).
TUMT versus TURP
Based on data from four studies with 306 participants, when compared to TURP, TUMT probably results in little to no difference in urologic symptom scores measured by the International Prostatic Symptom Score (IPSS) on a scale from 0 to 35, with higher scores indicating worse symptoms at short-term follow-up (mean difference (MD) 1.00, 95% confidence interval (CI) −0.03 to 2.03; moderate certainty). There is likely to be little to no difference in the quality of life (MD −0.10, 95% CI −0.67 to 0.47; 1 study, 136 participants, moderate certainty). TUMT likely results in fewer major adverse events (RR 0.20, 95% CI 0.09 to 0.43; 6 studies, 525 participants, moderate certainty); based on 168 cases per 1000 men in the TURP group, this corresponds to 135 fewer (153 to 96 fewer) per 1000 men in the TUMT group. TUMT, however, probably results in a large increase in the need for retreatment (risk ratio (RR) 7.07, 95% CI 1.94 to 25.82; 5 studies, 337 participants, moderate certainty) (usually by repeated TUMT or TURP); based on zero cases per 1000 men in the TURP group, this corresponds to 90 more (40 to 150 more) per 1000 men in the TUMT group. There may be little to no difference in erectile function between these interventions (RR 0.63, 95% CI 0.24 to 1.63; 5 studies, 337 participants; low certainty). However, TUMT may result in fewer cases of ejaculatory dysfunction compared to TURP (RR 0.36, 95% CI 0.24 to 0.53; 4 studies, 241 participants; low certainty).
TUMT versus sham
Based on data from four studies with 483 participants we found that, when compared to sham, TUMT probably reduces urologic symptom scores using the IPSS at short-term follow-up (MD −5.40, 95% CI −6.97 to −3.84; moderate certainty). TUMT may cause little to no difference in the quality of life (MD −0.95, 95% CI −1.14 to −0.77; 2 studies, 347 participants; low certainty) as measured by the IPSS quality-of-life question on a scale from 0 to 6, with higher scores indicating a worse quality of life. We are very uncertain about the effects on major adverse events, since most studies reported no events or isolated lesions of the urinary tract. TUMT may also reduce the need for retreatment compared to sham (RR 0.27, 95% CI 0.08 to 0.88; 2 studies, 82 participants, low certainty); based on 194 retreatments per 1000 men in the sham group, this corresponds to 141 fewer (178 to 23 fewer) per 1000 men in the TUMT group. We are very uncertain of the effects on erectile and ejaculatory function (very low certainty), since we found isolated reports of impotence and ejaculatory disorders (anejaculation and hematospermia).
There were no data available for the comparisons of TUMT versus convective radiofrequency water vapor therapy, prostatic urethral lift, prostatic arterial embolization or temporary implantable nitinol device.