TRANSURETHRAL MICROWAVE THERMOTHERAPY FOR BENIGN PROSTATIC HYPERPLASIA: PATIENT CHARACTERISTICS IN GOOD AND POOR RESPONDERS

Transurethral microwave thermotherapy (TUMT) has be'en shown to produce a clinical benefit in patients with symptomatic benign prostatic hyperplasia. In order to identify the features of the ideal candidate, a retrospective analysis was conducted in 32 patients who were followed for 2 mo or more. Good responders (GR) were defined as having their Siroky peak flow rate (PFR) standard deviation (SD) increase by 0.5 or a decrease in the International Prostatic Symptom Score (l-PSS) of 10 (22 patients). Poor responders (PR) were defined as having their PFR SD increase by 0.5 and their l-PSS decrease by10 (10 patients). The prostate volume, pre-TUMT l-PSS and intravesical opening pressure were significantly greater in the GR group, while there were no significant differences between the 2 groups for the other baseline patient characteristics: age, prostate length, PFR, PFR SD, post-voiding residual volume and quality of life. Concerning the operational parameters, significantly more total energy was delivered to the prostate in the GR group (mean 131 kJ) than in the PR group (mean 101 kJ). Moreover, the 7 patients with anti-androgen therapy pre-TUMT received less total energy and 5 of the 7 were poor responders. These results suggest that patients with apparent obstructive symptoms and with moderate enlargement of prostate could benefit more from this less invasive therapy. Clinical response seems to be dose-dependent and patients with a history of recent anti-androgen treatment may have a less favorable response. The histological composition of the prostatic tissue may play an important role as far as microwave thermal interactions and treatment outcome are concerned.     

TRANSURETHRAL MICROWAVE THERMOTHERAPY FOR BENIGN PROSTATIC HYPERPLASIA: CLINICAL RESULTS AFTER A 1-YEAR FOLLOW-UP

Since September 1992, 63 patients with symptomatic benign prostatic hyperplasia (BPH) have been treated with transurethral microwave thermotherapy (TUMT) using the Prostatron device. The International Prostate Symptom Score (l-PSS) and quality of life (QOL) score were used to evaluate subjective symptoms. The mean l-PSS (total, irritative and obstructive scores) and QOL scores had decreased by 40, 38, 45 and 40%, respectively, at 12 months (p < 0.0001). While the mean peak flow rate had increased by 72% (p < 0.001). The clinical efficacy at 12 months was 42%, using a modification of the response criteria proposed at the 2nd International Consultation on Benign Prostatic Hyperplasia. There were no significant differences in the baseline and treatment parameters between those who responded favorably to TUMT and those who did not. The total thermal dose delivered to the prostate did not predict clinical response. However, there was a positive correlation between l-PSS or QOL at baseline and % reduction at 3, 6 and 12 months, and a negative correlation between peak flow rate at baseline and % increase at 3 and 6 months. There were no major complications associated with TUMT during the follow-up period. In summary, our 1-year clinical results are compatible with previous reports, suggesting that TUMT is a safe, effective and lasting non-surgical treatment for BPH. However, evaluation of efficacy should be based on uniform criteria to facilitate comparisons of different clinical trials. The most suitable patient profiles for TUMT could not be identified by retrospective analysis.     

Transurethral microwave thermotherapy for benign prostatic hyperplasia: Relation between clinical response and prostate histology

The effectiveness of transurethral microwave thermotherapy (TUMT) for BPH has been confirmed. To identify the characteristics of the ideal candidate, retrospective analysis and morphometric study of prostatic tissue were performed. Forty-two patients with symptomatic BPH were included in the study; these comprised 10 patients treated for more than 3 months with anti-androgen pre-TUMT (group A) and 32 fresh cases (group B). Subjective and objective responses were evaluated at 2 months post TUMT. In 12 fresh cases who underwent pre-TUMT biopsy of the prostate, the stromal-to-epithelial ratio was determined via quantitative image analysis on a computer-assisted morphometry system. No significant differences in baseline patient characteristics were found between the two groups: age, prostate volume, peak flow rate (PFR), or International Prostate Symptom Score (I-PSS). However, significant differences in treatment outcome were found between the two groups (group A vs. group B, respectively): total energy delivered to the prostate: 96 kJ vs. 125 kJ; I-PSS decrease from baseline: 5.9 vs. 11.6; PFR increase from baseline: 1.1 vs. 4.7 ml/sec. There was a positive correlation between the I-PSS change from baseline and the stromal-to-epithelial ratio of the prostatic tissue (r = 0.4857). The results suggest that microwave interacts poorly with the prostate due to the artificially created “lack” of glandular tissue. The morphometric study also supports the contention that the histological composition of the prostatic tissue plays an important role in terms of microwave thermal interactions and treatment outcome. © 1996 Wiley-Liss, Inc.     

RESPONSE CRITERIA FOR THE THERAPEUTIC EFFICACY OF TREATMENT FOR BENIGN PROSTATIC HYPERPLASIA

Response criteria for the therapeutic efficacy of treatments for benign prostatic hyperplasia (BPH) were proposed following the International Consultation on BPH held in 1993. In the present study, we validated the criteria and proposed a simplified form, which consists of the responses of three parameters: symptom score and quality of life assessed by the international prostate symptom score and the maximum flow rate. Each of the three individual parameters is evaluated as one of four response grades: excellent, good, fair or poor, and the number of response grade of the three parameters determines the overall response. Excellent and Good responses are regarded as effective, and fair and poor are regarded as not effective. The validity of the response criteria was assessed by comparing the responses determined by these criteria with those made by physicians in charge using a group of 225 patients receiving various treatments. The agreement rates on effectiveness of overall responses between the response criteria and physicians were 77% for a multicenter trial of medical treatment (n = 94), 100% for TURP (n = 23), 92% for laser treatment (n = 47), 80% for thermal treatment (n = 26) and 78% for α-blockers (n = 35), respectively. Altogether, 88% (198 of 225 cases) were evaluated accurately regarding effectiveness. Addition of prostate volume to the battery of response parameters made little contribution to diagnostic accuracy. Deletion of any of the other three parameters, however, significantly compromised the quality of assessment. These results suggest that the proposed criteria may be useful as the standard method for the assessment of the clinical efficacy of BPH treatment.     

Pros-EightTM Transurethral Radiofrequency Thermotherapy for Benign Prostatic Hyperplasia: Preliminary Clinical Results

Background: We have developed a new transurethral thermotherapy device using 8MHz radiofrequency (RF) for the treatment of patients with symptomatic benign prostatic hyperplasia (BPH). We report the safety and effectiveness of the initial clinical experience with this device
Methods: Sixty patients with symptomatic BPH were subjected to a single 1-hour treatment under local anesthesia. The treatment device uses extracorporeal RF capacitive heating in combination with radiative heating and conductive cooling of the urethra.
Results: In the 49 patients evaluahle at 3 months, the mean International Prostate Symptom Score decreased from 17.8 to 13.1 ( P < 0.0001) and the Quality of Life score decreased from 4.4 to 3.4 (P < 0.0005). Maximum flow rate increased from 8.1 to 9.7mL/s (P< 0.05) at 3 months. Overall effectiveness by Homma's response criteria was as follows; excellent 4.1%, good 10.2%, fair 38.8% and poor 46.9%. Side effects were minimal. Gross hematuria was seen in 3 patients and erosion of the external urethral meatus was seen in 2 patients, but none had urinary retention.
Conclusions: In this initial clinical trial, transurethral RF thermotherapy was safe and resulted in modest symptomatic improvement. Further investigations for optimizing the treatment protocol seem warranted.     

Transurethral needle ablation of the prostate: An initial Japanese clinical trial

OBJECTIVES: Transurethral needle ablation of the prostate is a new alternative endoscopic thermal therapy that uses a low-energy radio frequency delivered into the prostatic adenoma. Herein is reported the initial clinical experience by multiple institutes in Japan of transurethral needle ablation of the prostate for the treatment of symptomatic benign prostatic hyperplasia. METHODS: A total of 93 patients were treated with this technique. Transurethral needle ablation of the prostate was generally performed under low-spinal anesthesia. Before and after the procedure, international symptom score (IPSS), quality of life (QOL) score, peak urinary flow rate (Qmax), postvoid residual urine volume and prostate size were evaluated. RESULTS: There was a reduction of IPSS of more than 50% when compared with that of pretreatment, being 51.3% (57/93 patients) and 60.2% (56/93 patients) at 3 months and 6 months after the procedure, respectively. Sixty-seven patients who were available for a 12-month follow-up period demonstrated a markedly decreased mean IPSS when compared with that measured before the treatment for a statistically significant difference (P < 0.01). Fifty-eight patients who were available for uroflowmetric study at 12 months exhibited a notably increased mean Qmax of 11.2 +/- 4.5 mL/s, which was a statistically significant increase when compared with that found before treatment (P < 0.05). Although all patients suffered some degree of gross hematuria after the procedure, none of them required any specific treatment for complications. CONCLUSION: Transurethral needle ablation technique for the treatment of symptomatic benign prostatic hyperplasia is safe and effective. However, a much longer follow-up study is essential for fully evaluating the extended effectiveness of this technique.     

IMMEDIATE AND POSTOPERATIVE COMPLICATIONS OF TRANSURETHRAL PROSTATECTOMY IN THE 1990s

PURPOSE: We compare the morbidity, mortality, hospitalization and urethral catheter time of contemporary transurethral prostatectomy to historical series, and evaluate recent trends in hospitalization and urethral catheter time during the last 8 years. MATERIALS AND METHODS: A retrospective chart review of 520 consecutive patients who underwent transurethral prostatectomy between 1991 and 1998 at a single institution for symptomatic benign prostatic hyperplasia was performed. Inpatient and outpatient charts, clinic records, operative reports and discharge summaries were reviewed. For each patient 43 data points were collected. Telephone followup was performed when data were lacking. All retrieved data were compiled in a computer database. Perioperative and late postoperative morbidity and mortality, hospitalization and urethral catheter time were analyzed. RESULTS: A total of 520 patients were identified with an average age of 67 years (range 44 to 89). Significant co-morbidity (2 or more co-morbid disease processes) was identified preoperatively in 30.3% of the patients. The most common indications for transurethral prostatectomy were lower urinary tract symptoms (80.9%) and urinary retention (15.2%). Average preoperative International Prostate Symptom Score was 23.8. Average weight of resected tissue was 18.8 gm. There was no perioperative patient mortality. Blood transfusion rate was 0.4%. The rate of intraoperative and immediate postoperative complications was 2.5% and 10.8%, respectively. Average hospital stay was 2.4 days, and 1.1 from 1997 through 1998. The rate of late postoperative complication was 8.5% and the average postoperative symptom score was 6.4 with an average followup of 42 months (range 6 to 84). CONCLUSIONS: Contemporary perioperative and postoperative complications of transurethral prostatectomy are significantly lower than rates in historical series. The average hospital stay and urethral catheter time have steadily decreased during the last 8 years.     

Transurethral microwave thermal therapy: Pathologic findings in the canine prostate

Microwave irradiation administered by transurethral transducer to the prostate permits focused hyperthermia with resultant tissue ablation; a cooling system within the catheter allows urethral preservation. We evaluated the effect of microwave hyperthermia in 13 dogs receiving 48–79 min of focused irradiation (16–45 watts, intraprostatic temperature >45°C) delivered by a specially-designed transducer with an operator-controlled directional antenna (T3, Urologix Inc., Minneapolis, MN); one other dog had transducer placement without irradiation (sham control). After treatment, the dogs were in good health, voiding well without complications, and were sacrificed after 5–38 days. The prostate and vasa deferentia were removed, fixed in 10% formalin, grossly inspected, cut at 5 mm intervals, and serially sectioned with whole mount sections; representative sections of the adjacent rectum and distal bladder were also obtained. All cases were histologically evaluated with prostatic mapping without knowledge of treatment or time of sacrifice. In the acute phase (5–13 days), the prostate showed sharply circumscribed periurethral coagulative necrosis with hemorrhage; necrosis was also seen in the mucosa and bladder wall of those with transducers placed at the bladder neck. In the subacute phase (17 days), the hemorrhagic necrosis was resolving, often with cystically dilated urethra due to sloughed necrotic tissue; the urothelium was intact. By 24–38 days, the necrosis was in the late stages of resolution, with residual patchy acute and chronic inflammation at the periphery, and frequent persistence of megalourethra. In all cases, the prostatic capsule was intact, the urethral mucosa was preserved, and the vasa deferentia and rectum were normal except for two cases with mild fat necrosis. Microwave irradiation allows precisely localized thermal ablation of prostatic tissue and enlargement of the urethral bore without clinical complications in dogs, offering promise as a therapeutic alternative to surgery in select patients with symptomatic prostatic nodular hyperplasia.     

TOTAL DOSE IRON INFUSION: SAFETY AND EFFICACY IN PREDIALYSIS PATIENTS

Iron deficiency anemia isnot uncommon in predialysis patients. Oral iron often cannot maintain adequate iron stores. Hence we evaluated the safety and efficacy of total infusion (TDI) of iron in these patients. Anemic predialysis patients were screened and those with Hb < 7.0g/dL and serum ferritin < 200ng/mL were selected. Patients with active bleeding and acute livere disease were excluded. All patients were on oral iron 100mg/day. None of the patients were on erytropoeitin. 11 patients (6 males and 5 females). aged 45.9 + 15yrs. were suitable. Hb was 5.9 ± 1.0g/dL and serum ferritin was 89.5 + 50 ng/mL. The preparation used was iron dextran. A test dose of 25mg in 100mL normal saline was administeted over 1 hr to all patients. One patient had fever and chills during the test dose and was not given TDI. 10 patients received TDI. None of these patients had any problem during the infusion. The dose of iron administered was 900 + 316.2 mg. One patient who received 1600mg had arthralgia-myalgia and another patient had thrombophlebitis following TDI. One month after TDI, Hb was 8.0 + 1.0g/dL and serum ferritin was 362ng/mL. We feel that TDI is a safe and effective method of correcting iron deficiency in predialysis patients.     

A coaxial microwave applicator for transurethral hyperthermia of the prostate

Benign prostatic hyperplasia (BPH) is a common disease of elderly men. The current definitive treatment for urinary obstruction caused by this disease is surgery (transurethral resection of the prostate, or TURP). Recent evidence suggests that hyperthermia may be a useful nonsurgical alternative for treatment of symptomatic BPH. A transurethral microwave applicator has been designed around a Foley catheter for delivery of local hyperthermia to the prostate. The Foley balloon is used to maintain the antenna position within the prostatic urethra. The Foley catheter also features an antenna choke to confine power deposition to the intended region. The antenna is a coaxial dipole designed to operate at 915 MHz. Qualitative and quantitative specific absorption rate (SAR) patterns are shown for this antenna. In vivo experiments in dog prostate demonstrate that temperatures >42°C can be obtained > 1 cm away from the catheter, while maintaining a maximum urethral temperature of 47°C to 48°C. Histology obtained acutely after the hyperthermia treatments showed minimal damage to the periurethral tissues. We conclude from these studies that this microwave applicator is capable of providing local hyperthermia to the prostatic tissues with a predictable and well-circumscribed thermal distribution. © 1993 Wiley-Liss, Inc.     

良性前列腺增生症的微创治疗进展

良性前列腺增生症（BPH）是中老年男性泌尿生殖系统最常见的疾病之一,而外科手术治疗是治愈此疾病的唯一手段,传统的外科手术方法主要是开放前列腺摘除手术及经尿道前列腺切除术（TURP）,但因手术创伤较大及术中并发症较多,其在外科手术治疗中的主导地位不断受到各类新近微创治疗方法的挑战,其中一部分已成为治疗良性前列腺增生症的重要手段。本文就微创治疗技术在治疗良性前列腺增生症的发展作一综述,以供临床参考。     

THE EFFECT OF FINASTERIDE ON PROSTATE VOLUME,URINARY FLOW RATE AND SYMPTOM SCORE IN MEN WITH BENIGN PROSTATIC HYPERPLASIA

This study was designed to determine the efficacy of the 5α-reductase inhibitor finasteride (Proscar, MK-906) in men with reduced urinary flow rates and symptoms of urinary outflow obstruction secondary to benign prostatic hyperplasia. Forty-five men were randomized to one of three groups receiving either placebo, 1 mg/day or 5 mg/day tinasteride for the first 12 months of the study period. At the end of this period all men received 5 mg/day finasteride for a further 2 years. Efficacy was determined by measurement of prostate volume, maximum urinary flow rate, and symptom score using a modified Boyarsky assessment. Prostate volume reduced by 20 and 27%. respectively, for those on 1 and 5 mg after the first year. At 3 years the volume had reduced by 43%. This reduction in prostate volume was associated with an improvement in maximum urinary flow rate by 50% (1 mg), and 35% (5 mg) at 1 year, and 36% at 3 years. The total, obstructive and non-obstructive symptom scores decreased (improved) for patients on 1 and 5 mg tinasteride, with the total score reducing by 33% from baseline at year 3. The results demonstrate that finasteride causes a modest but signiticant clinical improvement in men with urinary outflow obstruction secondary to benign prostatic hyperplasia.     

A PROSPECTIVE STUDY OF THE SAFETY AND EFFICACY OF SUPRAPUBIC TRANSVESICAL PROSTATECTOMY IN PATIENTS WITH BENIGN PROSTATIC HYPERPLASIA

PURPOSE: We investigate the safety and efficacy of suprapubic transvesical prostatectomy, and the change in bladder wall thickness after surgery. MATERIALS AND METHODS: We conducted a prospective 1 center study of 32 consecutive patients who underwent transvesical prostatectomy from December 1996 to March 1997 for benign prostatic hyperplasia with large prostate volume, who were followed for 1 year. Pressure flow study and transrectal sonography were performed at baseline and repeated at 6 months. Bladder wall thickness was measured at baseline and regular intervals postoperatively. A morbidity questionnaire was completed during the first 6 weeks after surgery. RESULTS: An average of 63 gm. prostate adenoma were enucleated at surgery. An indwelling catheter was required for an average plus or minus standard deviation of 5.4 +/- 2.6 days after treatment. The International Prostate Symptom Score decreased from 19.9 +/- 4.4 to 1.5 +/- 2.7 and the quality of life score decreased from 4.9 +/- 1.0 to 0.2 +/- 0.4 at year 1, respectively. Maximum flow rate improved from 9.1 +/- 5.3 to 29.0 +/- 8.9 ml. per second. Residual urine decreased from 128 +/- 113 to 8 +/- 18 ml. Before surgery 30 patients had obstruction and 2 were in the equivocal zone of the International Continence Society nomogram. At 6 months after prostatectomy 30 patients did not have obstruction, and 2 who were subsequently operated on for bladder neck sclerosis were equivocal and had obstruction, respectively. No patient had significant postoperative bleeding and no heterologous blood transfusions were required. There were 4 men who had urinary tract infection and 1 who had wound infection. A slight decrease in erectile function was observed 6 weeks postoperatively, and no change in patient libido and quality of sex life was reported. The total complication rate was 31.3%. The bladder was unstable in 7 men before and 3 after surgery. A significant decrease in bladder wall thickness was observed from 5.2 +/- 0.7 at baseline to 2.9 +/- 0.9 mm. at year 1 postoperatively. CONCLUSIONS: Our study confirms the excellent clinical outcome of transvesical prostatectomy, and rapid improvement of most subjective and objective parameters during the 4 weeks after surgery. Bladder hypertrophy appears to be significantly reduced after prostate surgery. The urodynamic results in patients who underwent open surgery probably represent the maximum obtainable relief of obstruction and should be considered the reference standard to which all other treatments, including transurethral resection, should aspire.     

ASSESSMENT OF SEXTANT BIOPSY OF THE PROSTATE FOR DETECTING CANCER PRIOR TO THERAPY IN PATIENTS CLINICALLY DIAGNOSED AS BENIGN PROSTATIC HYPERPLASIA

Pathological results and perioperative morbidity were compared in 199 patients who had undergone prostatectomy and/or biopsy in order to determine the extent to which systematic biopsy is effective for detecting prostate cancer prior to therapy in patients clinically diagnosed as having benign prostatic hyperplasia. Seventeen (8.5%) cancers were detected in 199 patients following surgery and/or biopsy. Digitally-guided biopsy as a means of detecting prostate cancer was found to be just as effective as ultrasound-guided biopsy. Seven (12.5%) cancers were detected in 56 patients who had undergone biopsy and transurethral resection. Preprostatec to my biopsy detected only two of three patients with stage TIb disease. All four stage TIa and one stage TIb failed to be diagnosed. Of 90 patients who had biopsy prior to surgery other than TURP, seven (7.8%) cancers were found. Four of these were advanced. The incidence of postoperative fever > 38.0 °C and duration of postoperative pyuria did not differ significantly between groups with or without biopsy. Preoperative biopsy did not contribute to perioperative morbidity. Tumors detected by systematic biopsy are usually large and clinically significant. Positive biopsy results are often diagnostic, but the pathological features of a tumor together with clinical parameters should be considered to reduce the chance of overdiagnosing an insignificant tumor. Sextant biopsy would be most applicable to patients scheduled for any type of therapy other than TURP especially in those with markedly elevated serum PSA levels. This procedure may be beneficial particularly for younger patients with long life expectancy who will benefit from definitive therapy.