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2 /96/ S03.00/0 T h e J o u r n a l of U rolouy Copyrght 1996 by A m ercan U rologcal A sso c a to n, n c. Vol. 156, , July 1996 Prnted n U.S.A. HGH ENERGY THERMOTHERAPY N THE TREATMENT OF BENGN PROSTATC HYPERPLASA: RESULTS OF THE EUROPEAN BENGN PROSTATC HYPERPLASA STUDY GROUP J. J. M. C. H. DE LA ROSETTE, M. J. A. M. d e WLDT, K. HOFNER, S. St. C. CARTER, F. M. J. DEBRUYNE a n d A. TUBARO From the Departments of Urology, Njmegen Unversty Hosptal, Njmegen, The Netherlands, Hannover Medcal School, Hannover, Germany, Hammersmth Hosptal Trust, London, Unted Kngdom, and UAqula Unversty School of Medcne, UAqula, taly ABSTRACT Purpose: We documented the results of hgh energy tran sureth ral mcrowave therm otherapy n the treatm ent of bengn pro statc hyperplasa. M aterals and Methods: We evaluated 116 patents followng tran sureth ral mcrowave th erm otherapy accordng to symptom scores, transrectal ultrasound, free vodng and pressure-flow study param eters. Results: Sgnfcant m provement was noted n all objectve and subjectve param eters. Moreover, cavtes n the prostatc urethra were observed n almost 40% of the patents. Conclusons: Hgh energy transurethral mcrowave therm otherapy s an effectve therapy for bengn prostatc hyperplasa. Patents w th larger prostates and moderate to severe bladder outlet obstructon seem to be the best canddates for ths hgher energy therm otherapy protocol, although morbdty s ncreased. Key Words: prostatc hypertrophy; hypertherma, nduced; mcrowaves Bladder outlet obstructon n men has been a clncal problem throughout medcal hstory. As early as the 17th century t was suggested that bengn prostatc hyperplasa (BPH) could result n mechancal obstructon of the bladder outlet, whch may eventually cause lower urnary tract symptoms, neffcent bladder emptyng wth poor urnary flow and/or post-mcturton resdual urne.1at ths juncture the patent usually seeks medcal advce ether because of troublesome symptoms or complants secondary to the worsened vodng, for example recurrent urnary tract nfectons. Presently, transurethral resecton of the prostate s the gold standard therapy for BPH, affordng excellent results n the hands of the experenced surgeon. The success of transurethral resecton of the prostate s defned by the mmedate removal of obstructng prostatc tssue resultng n the formaton of cavtes. Long lastng mprovement n symptoms and vodng parameters s acheved wthn a few days of treatment. However, ths operaton s not to be taken lghtly. Although the mortalty rate has decreased to 0.5%,2 the morbdty rate after transurethral resecton of the prostate s stll 18% and has not altered sgnfcantly wthn the last 15 years. Consequently, despte the proved safety and effcacy of ths procedure, ts morbdty as well as ts relatvely hgh cost and nvasve nature have led many nvestgators to search for an alternatve treatment. Many technques that mnmze the physologcal effects assocated wth prostatc surgery are currently beng assessed, ncludng use of prostatc stents,3 transurethral needle ablaton,^ hgh ntensty focused ultrasound,5 transurethral mcrowave thermotherapy6 and laser therapy.7 The queston as to whch technque s approprate n any ndvdual s answered largely by knowng the outcome of each of these therapes. Despte the encouragng results clamed for all of the new technques, transurethral resecton of the Accepted for publcaton January 26, Edtor s Note: Ths artcle s the fourth of 5 publshed n ths ssue for whch category 1 CME credts can be earned. nstructons for obtanng credts are gven wth the questons on pages 222 and prostate contnues to surpass ts compettors. However, the results of hgh energy thermotherapy seem to shed a new lght on ths dscusson. The results reported wth lower energy thermotherapy usng Prostasoft 2.0 n the treatment of BPH are promsng. Overall symptomatc mprovement has been reported n the majorty of patents n conjuncton wth mprovement of vodng parameters.8-10 The Madsen symptom score decreased from a mean of 13 before treatment to about 4 after treatment, whle mean maxmum flow change ranged from 2 to 3 ml. per second. t has been suggested that the placebo response wth ths modalty may contrbute consderably to treatment outcome. However, 5 sham controlled studes have demonstrated that the effect of transurethral mcrowave thermo therapy s greater than can be accounted for by ether the assocated urethral nstrumentaton or by any placebo effect.11 The re-treatment rate after transurethral mcrowave thermotherapy was reportedly 0.5 to 11% at 1 year of followup An ncrease n thermal dose can be seen wth the evoluton of thermal treatment modaltes. The elevaton of ntraprostatc temperatures as measured by nvasve thermometry durng transurethral mcrowave thermotherapy usng verson 2.0 operatng software has been shown to be broadly correlated wth clncal outcome.13 Program verson 2.0 was modfed to provde more power at a maxmum of 70 watts, and uses a hgher rectal threshold leadng to an ncrease n the energy delvered to the prostate. Ths new verson of the operatng software, known as Prostasoft verson 2.5, s currently under evaluaton. n contrast to earler reports on results acheved wth lower energy thermotherapy, the results wth these hgher energy levels seem to be excellent, and n a subgroup of patents they are even comparable to those of surgcal therapy. We present the results of a multcenter study usng hgh energy thermo therapy for the treatment of BPH. Technomed Medcal Systems, Lyon, France.

3 98 HGH ENERGY THERMOTHERAPY FOR BENGN PROSTATC HYPERPLASA PATENTS AND M ETHODS Patents recruted for the study had a Madsen symptom score of 8 or more, max mum flow rate 15 ml. per second or less, post-vod resdual 350 ml. or less and voded volume 100 ml. or more. Assessm ent of these patents ncluded hstory wth symptom scores, physcal examnaton wth dgtal rectal examnaton, bochemstry nvestgatons ncludng prostate specfc antgen, urnalyss, urne culture, transrectal ultrasonography of the prostate, uroflowmetry, post-vod resdual measurement and a urodynamc nvestgaton ncludng pressure-flow studes. The results of hgh energy thermotherapy n 116 men wth lower urnary tract symptoms and BPH were evaluated, and outcome was correlated wth prostate sze, nternatonal Prostatc Symptom Score (-PSS), Madsen symptom score, free flow vodng parameters and grade of bladder outlet obstructon. Followup was performed at 4, 12, 26 and 52 weeks after treatment. We used the Prostatron:!: devce wth a COO treatment catheter consstng of a mcrowave dpole antenna postoned 10 mm. below the Foley balloon and mounted n a water cooled transurethral probe. Verson 2.5 of the hgh energy operatng software provdes power at a maxmum of 70 watts wth a rectal threshold set at 43.5C. Transurethral mcrowave thermotherapy has been descrbed prevously.14 Uroflowmetry was performed, and the post-vod resduals were determned by transabdomnal ultrasound usng the ellpsod formula. Urodynamc nvestgatons were performed wth a transurethral catheter equpped wth an ntravescal mcrotp pressure sensor for bladder pressure recordngs. The abdomnal pressure was recorded ntrarectally wth a mcrotp sensor catheter. Commercally avalable equpment was used to record the pressure and flow data. The dgtally stored data were translated to a urodynamcs analyss computer program developed at our department. To provde objectve and precse grades of obstructon, pressure- flow study graphs were ftted to a passve urethral resstance relaton curve. The mnmal urethral openng pressure and theoretcal urethral lumen were calculated automatcally.15 The urethral resstance factor was computed to enable the classfcaton of patents on a contnuous, 1 parameter scale of obstructon.16 We also added a non parametrc analyss of obstructon usng a classfcaton accordng to the lnear passve urethral resstance relaton pressure-flow study nomogram.17 RESULTS Between Aprl 1993 and July 1994, 116 patents were treated wth hgh energy transurethral mcrowave thermotherapy usng the Prostasoft 2.5 software. Patent age at baselne ranged from 50 to 87 years (mean 66.6) and average prostate volume plus or mnus standard devaton was 51 ± 21 cm.3 (range 20 to 154). Madsen symptom scores ranged from 8 to 23 (mean 13.6 ± 3,6). Uroflowmetry parameters showed a maxmum flow rate of 3 to 15 ml. per second (mean 9.6 ± 3.3), voded volume 100 to 697 ml. (mean 227 ± 127) and post-vod resdual 0 to 350 ml. (mean 73 ± 79). An average of 147 ± 44 kj. (range 28 to 209) of mcrowave energy were admnstered durng treatment. Of the patents 67 have reached 1 year of followup, whle 105 were followed 26 weeks. Among the 11 patents who were not seen at 26 weeks 2 ded of nontreatment related causes (1 of termnal heart falure 4 months after treatm ent and 1 of pulmonary falure due to a 1-anttrypsn defcency), 3 underwent transurethral resecton of the prostate and 6 were lost to followup. Mean Madsen symptom score at baselne was 13.6, and mproved to 9.4 at 4 weeks, 6.0 at 12 weeks, 5.5 at 26 weeks and 4,9 at 52 weeks of followup (fg. 1, A). The -PSS showed a smlar pattern, wth mprovement from a m ean of 17.5 at baselne to 13.9 at 4 weeks, 8.2 at 12 weeks, 7.9 at 26 weeks and 7.1 at 52 weeks of followup (fg. 1, B). Maxmum flow rate mproved from 9.6 ml. per second at baselne to 9.8 at 4 weeks, 15.2 at 12 weeks and 14.1 at 26 weeks of followup. These mprovements were sustaned to 52 weeks, wth a maxmum flow rate of 14.5 ml. per second (fg. 1, C). The voded volume durng followup ncreased slghtly (fg. 2, A), whle the post-vod resdual decreased sgnfcantly from 73 ml. at baselne to 40 ml. at 4 weeks, 27 at 12 weeks, 33 at 26 weeks and 25 at 52 weeks of followup (fg. 2, B). Mean duraton of transurethral dranage was 14.3 ± 15.2 days (range 0 to 105). Transrectal ultrasonography at 3 months of followup dentfed a cavty n 37% of the patents (fg. 3). There appeared to be good statstcal correlaton between the presence of cavtes and uroflowmetry mprovement (p = 0.003). M axmum flow rate mproved from 9.7 ml. per second at baselne to 17.9 ml. per second n patents wth a cavty on transrectal ultrasound and from 9.6 to 13.6 ml. per second n those wthout a cavty. Currently, data for 83 patents are avalable for urodynamc analyss. At 6 months after transurethral mcrowave thermotherapy a statstcally sgnfcant mprovement was noted for all pressure-flow parameters, whch s also clearly llustrated n the Abrams-Grffth nomogram (fg. 4 and table 1). Baselne parameter stratfcaton versus treatm ent outcome showed that partcularly patents wth larger prostates and moderate to severe bladder outlet obstructon respond best to hgh energy transurethral mcrowave thermotherapy (table 2). These patents showed a sgnfcant mprovement n objectve and subjectve parameters. The relatonshp between maxmum flow rate at baselne and treatment outcome was much less. There appeared to be no relatonshp between treatm ent outcome and M adsen symptom score at baselne. Hgh energy thermotherapy resulted n consderable morbdty. rrtatve vodng complants were noted n a large number of patents for up to 2 to 4 weeks, and transent hematura was present n most patents durng the frst days after treatment. Fnally, retrograde ejaculaton was documented n a thrd of the patents who had antegrade ejaculaton before treatment. r> B 20 r 18 3u LO c s t o 8 E 5 f> 3 Q) bs o CJ (/> e n. E >% to w f [ & K ll N - 1(6 kucenc 03 Week.1 m W e e k Week Wwsfc KASELNr 116 W M E K 4 m W m - K 12 KM WE.'PK 26 6 A W :E ; K N = 114 N A S T l N C 108 WR KA 10 6 WEKK 12 WEEK 26 W EEK 52 FOLLOW-UP FO LLO W -U P FOLLOW-UP F g. 1. Changes n clncal parameters after treatment wth means and standard errors. A, Madsen symptom score., -PSS. C, maxmum free flow, N, number of patents.

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5 100 HGH ENERGY THERMOTHERAPY FOR BENGN PROSTATC HYPERPLASA T a b le 1. Urodynamc data at baselne and after treatment Before Treatment Mean ± SD After Treatment Pressure at maxmum flow 64 ± ± 16 Lnear passve urethral 2,9 ± ± 1.1 resstance relaton Urethral resstance factor 41 ± ± 11 Mnmal urethral openng 33 ± ± 9 pressure Theoretcal urethral lumen 2.8 ± ± 5.1 pulmonary dseases and hgh operatve rsks, a mnmally nvasve treatment has been sought, ncludng medcaton2021 and nstrumentaton.3 7 Wth the concept of transurethral mcrowave thermotherapy as an outpatent and anesthesa-free procedure, and the encouragng clncal results acheved to date, much effort has been concentrated on developng ths treatment modalty. Applcaton of hgher energy levels for thermotherapy usng Prostasoft 2.5 software was frst reported by Devonec6 and de la Rosette11 et al, who demonstrated clncally sgnfcant mprovement. Our present multcenter study confrms these results. The changes n subjectve parameters usng the hgh energy Prostasoft 2.5 software s smlar to the mprovement noted n patents treated wth the Prostasoft 2.0 verson.6 However, when comparng the objectve parameters, a sgnfcantly better outcome n terms of urnary peak flow change was noted. A statstcally sgnfcant ncrease n maxmum flow of 9.6 to 15.2 ml. per second was noted at 12 weeks after transurethral mcrowave thermotherapy, whch was sustaned to at least 1 year. Mean post-vod resdual also mproved sgnfcantly from 73 to 27 ml. at 12 weeks and 25 ml. at 1 year. Ths objectve mprovement n uroflowmetry results was much more pronounced than n patents treated wth the lower energy software. Transrectal ultrasound magng of the prostate dentfed a cavty n 37% of the patents at 3 months after treatment (fg. 3). A postve correlaton between the presence of such a cavty and urnary flow rate mprovement was observed. One may conclude that more energy delvered to the prostate seems to result n greater mprovement n objectve parameters, whch may be explaned by the creaton of cavtes wthn the prostate. However, when such a cavty s absent the treatment should not be regarded as a falure because uroflowmetry may mprove ndependent of cavtjf formaton. Although uroflowmetry s an excellent method to document the act of mcturton, and t may ndcate whether an abnormalty s present, ts role n defnng the grade of obstructon s lmted.22 For transurethral mcrowave thermotherapy to be regarded as proper therapy for BPH, t must be able to releve the outlet obstructon. Advanced urodynamcs, ncludng pres sure-flow study analyss, are consdered the best methods to document changes n the grade of obstructon.22 The changes n pressure-flow study parameters were only moderate wth the lower energy Prostasoft 2.0 software. We concluded that only a certan type of obstructon responded favorably to thermotherapy n general, however, severe obstructon s not cured followng low energy thermo therapy. Analyss of the urodynamc data at 6 months after transurethral mcrowave thermotherapy usng Prostasoft 2.5 showed that 80% of obstructon patents appeared to be cured (fg, 4). A sgnfcant decrease n all obstructon parameters was noted overall (table 1), One can conclude that transurethral mcrowave thermotherapy usng Prostasoft verson 2.5 s able to releve bladder outlet obstructon. From an earler study we learned that no sngle clncal parameter could predct whch patents would respond best to low energy thermotherapy.25 Usng hgh energy thermotherapy t appears that patents wth more severe outlet obstructon and larger prostates wll respond best. Further studes are requred to explan ths phenomenon. A possble explanaton for the favorable outcome of treatment of larger prostates s a dfference n tssue composton and tssue perfuson. t s well known that stromal tssue responds dfferently to heat than glandular tssue.26 Larger prostates may have a dfferent dstrbuton of stromal and glandular tssue, and consequently they may respond dfferently to thermotherapy. We also know that the temperature ncrease n the prostate depends strongly on the tssue perfuson, and that perfuson s known to ncrease wth temperature durng thermotherapy.27>28 One can speculate that n larger prostates the tssue perfuson s less effcent than n smaller prostates, and that perhaps as a consequence hgher temperatures can be acheved resultng n necross wth formaton of a cavty. Current thermotherapy systems do not consder the effect of tssue perfuson on the effcacy of the treatment. Although urne flow s mproved, the morbdty caused by hgh energy transurethral mcrowave thermotherapy s ncreased compared to lower energy protocols. The hgh energy treatment s well tolerated by the patents but pan medcaton must be admnstered before or durng therapy n most cases. On a tral and error bass, 30 mg. morphne sulfate admnstered 2 hours before therapy resulted n an almost complant-free treatment. f requested, patents also were gven ether 10 mg. dazepam and/or 0,10 mg, fentanyl durng treatment. Percepton of dscomfort durng transurethral mcrowave thermotherapy may vary from a mld sensaton of perneal warmth and a mld urge to urnate to sgnfcant dscomfort. However, the morbdty s clearly lower wth transurethral mcrowave thermotherapy than wth transurethral resecton of the prostate. Transurethral mcrowave thermotherapy can stll be performed as an outpatent procedure wthout general anesthesa, and t s partcularly well suted for patents n poor health. Occasonally, hematura and tssue slough are noted, and urnary retenton s ex T a b l e 2. Outcome of subjectve (Madsen symptom score) and objectve (maxmum flow and pressure at maxmum flow) parameters accordng to results of maxmum flow at baselne, prostate volume and grade of obstructon - No. Pts. Mean Madsen Symptom Score ± SD Mean Maxmum Free Flow ± SD Mean Detrusor Pressure at Maxmum Flow ± SD Baselne 12 Wks. Baselne 12 Wks. Baselne 26 Wks. Maxmum free flow (ml./sec.): 12 or More ± ± ± ± ± ± 17 Less than ± ± ± ± ± ± 15 Prostatc vol. (cc): 40 or More ± ± ± ± ± 16 Less than ± ± ± ± ± ± 15 Lnear passve urethral resstance relaton: 3 or More ± ± ± ± ± ± 17 Less than ± ± ± ± ± ± 13

6 HGH ENERGY THERMOTHERAPY FOR BENGN PROSTATC HYPERPLASA 101 pected n almost all patents. Catheterzaton nterval averaged 14.3 days (range 0 to 105) and patents wth larger prostates requred longer catheterzaton perods than those wth smaller prostates. The fndng of retrograde ejaculaton n a thrd of our patents s n contrast to those documented wth lower energy thermotherapy, n whch antegrade ejaculaton was unchanged n the majorty of patents.29 No bladder neck contracton or urethral strctures have been noted to date. Treatment was repeated n 3 patents because they were not satsfed wth the result. From the long-term folowup data usng Prostasoft 2.0 we have learned that the re-treatment rate at 1 year s estmated up to 10%,30 whle 3-year followup data by de Wldt and de la Rosette,27 and Dahlstrand et al31 ndcate that clncal beneft s sustaned for ths perod. One may expect that the results acheved wth the hgher energy software are at least as good. n concluson, hgh energy transurethral mcrowave thermotherapy shows sgnfcant subjectve and objectve mprovement. The best canddates are patents wth moderate to severe bladder outlet obstructon and larger prostates. Formaton of cavtes after treatment correlated well wth better clncal outcome. REFERENCES 1. Shelley, H. S.: The enlarged prostate. A bref hstory of ts treatment. J. Hst. Med. Alled Se,, 24: 452, Mebust, W. K., Holtgrew, H. L., Cocket, A. T. K. and Peters, P. C.: Transurethral prostatectomy: mmedate and postoperatve complcatons. A cooperatve study of 13 partcpatng nsttutons evaluatng 3,885 patents. J. UroL, 141; 243, Mlroy, E. J. G.: Prostatc stents. Curr. Opn. Urol., 5: 25, Schulman, C. C. and Zlotta, A. R.: Transurethral needle ablaton of the prostate: a new treatment of bengn prostatc hyperplasa usng ntersttal low-level radofrequency energy. Curr. Opn. UroL, 5: 35, Madersbacher, S., Kratzk, C., Susan, M. and Marberger, M.: Tssue ablaton n bengn prostatc hyperplasa wth hgh ntensty focused ultrasound. J. Urol., 152: 1956, Devonec, M., Carter, S. St. C., Tubaro, A.} de la Rosette, J., Höfner, K, Dahlstrand, C. and Perrn, P.: Mcrowave therapy. Curr. Opn. Urol., 5: 3, Anson, K. and Watson, G.: The current status of the use of lasers n the treatment of bengn prostatc hyperplasa. Brt. J. UroL, suppl. 1, 75: 34, Blute, M. L., Tomera, K. M., Hellersten, D, K., McKel, C. F., Jr., Lynch, J. H., Regan, J. B. and Sankey, N. E.: Transurethral mcrowave thermotherapy for management of bengn prostatc hyperplasa: results of the Unted States Prostatron cooperatve study. J. UroL, part 2, 150: 1591, de la Rosette, J. J., Froelng, F. M. and Debruyne, F. M.: Clncal results wth mcrowave thermotherapy of bengn prostatc hyperplasa. Eur. UroL, suppl. 1, 23: 68, Tubaro, A., Paradso Galatoto, G., Trucch, A., Began, A., Stoppaccaro, A,, Trucc, E., Began Provncal, R., Furbetta, A., Laurent, C., Albanese, R. and Mano, L.: Transurethral mcrowave thermotherapy n the treatment of symptomatc bengn prostatc hyperplasa. Eur. UroL, 23: 285, de la Rosette, J. J., Tubaro, A., Höfner, K. and Carter, S. St. C.: Transurethral mcrowave thermotherapy: past, present and future. World J. UroL, 12: 352, Carter, S. St. C., Ogden, C. and Patel, A.: Long-term results of transurethral mcrowave thermotherapy for bengn prostatc obstructon. n: Urology Edted by P. Puppo. Bologna: Monduzz, pp , Carter, S. and Ogden, C.: ntraprostatc temperature v. clncal outcome n T.U.M.T. s the response heat-dose dependent? J. UroL, part 2, 151: 416A, abstract 756, de la Rosette, J. J. M. C. H. and Debruyne, F. M. J.: Transurethral thermotherapy. n: Contemporary BPH Management. Edted by P. Puppo. Bologna: Monduzz, pp , Schäfer, W.: The contrbuton of the bladder outlet to the relaton between pressure and flow rate durng vodng. n: Bengn Prostatc Hypertrophy. Edted by F. Hnman, Jr. and S. Boyarsky. New York: Sprnger-Verlag, pp , Grffths, D., van Mastrgt, R. and Bosch, R.: Quantfcaton of urethral resstance and bladder functon durng vodng, wth specal reference to the effects of prostate sze reducton on urethral obstructon due to bengn prostatc hyperplasa. Neurourol. Urodynam, 8: 17, Schafer, W., Waterbar, F., Langen, P.-H. and Deutz, F.-J,: A smplfed graphc procedure for detaled analyss of detrusor and outlet functon durng vodng. Neurourol. Urodynam., suppl., 8: 405, abstract 78, Hald, T.: Urodynamcs n bengn prostatc hyperplasa: a survey. Prostate, suppl., 2: 69, Boyle, P.: New nsghts nto the epdemology and natural hstory of bengn prostatc hyperplasa. n: Bengn Prostatc Hyperplasa: Recent Progress n Clncal Research and Practce. Edted by K Kurth and D. W. W. Newlng. New York: Wley- Lss, nc., secton, pp. 3-20, Stoner, E. and members of the Fnasterde Study Group: Threeyear safety and effcacy data on the use of fnasterde n the treatment of bengn prostatc hyperplasa, Urology, 43: 284, Lepor, H. for the Terazosn Research Group: Long-term effcacy and safety of terazosn n patents wth bengn prostatc hyperplasa. Urology, 45: 406, Blavas, J., Nordlng, J., Grffths, D. J,, Kondo, A,, Kayanag, T., Neal, D,, Schafer, W, and Yalla, S.: The objectve evaluaton of bladder outflow obstructon. n: The 2nd nternatonal Consultaton on Bengn Prostatc Hyperplasa (BPH). Edted by the World Health Organzaton. Jersey, Channel slands: Scentfc Communcaton nternatonal Ltd., pp , Tubaro, A., Carter, S. St. C., de la Rosette, J., Hofner, K., Trucch, A., Ogden, C., Mano, L., Valent, M., Jonas, U. and Debruyne, F.: The predcton of clncal outcome from transurethral mcrowave thermo therapy by pressur e-flow analyss: a European multcenter study. J. UroL, 153: 1526, de la Rosette, J. J. M. C. H., Tubaro, A, Trucch, A., Carter, S. St. C. and Hcfner, K: Changes n pressure-flow parameters n patents treated wth transurethral mcrowave thermotherapy. J. UroL, 154: 1382, de Wldt, M. J, A. M,, Tubaro, A., Hofner, K., Carter, S. St. C., de la Rosette, J. J. M. C, H. and Devonec, M.: Responders and nonresponders to transurethral mcrowave thermotherapy: a multcenter retrospectve analyss. J. UroL, 154: 1775, Hefty, R., Mattfeld, T., Gottfred, H. W., Klenschmdt, K. and Hautmann, R. E.: The crtcal role of the epthelum-stromarato n the laser treatment of BPH. J. Urol., part 2,153:231A, abstract 10, de Wldt, M. J. A. M. and de la Rosette, J. J. M. C, H.: Transurethral mcrowave thermotherapy: an evolvng technology n the treatment of bengn prostatc enlargement. Brt. J. UroL, 76: 531, Tubaro, A., Paradso Galatoto, G., Vcentn, C., Mano, R., Maner, C. and Mano, L.: The mpact of transurethral mcrowave thermotherapy on prostate blood perfuson. A color flow Doppler sonography study. SU 23rd Congress, Sydney, abstract 608, Laduc, R,, Bloem, F. A. and Debruyne, F. M.: Transurethral mcrowave thermo therapy n symptomatc bengn pro statc hyperplasa. Eur. UroL, 23: 275, de Wldt, M. J. A. M., de la Rosette, J. J. M. C. H. and Debruyne, F. M. J.: Retreatment rate after surgcal and non-surgcal treatment. n; Bengn Prostatc Hyperplasa: Recent Progress n Clncal Research and Practce. Edted by K. Kurth and D. W. W. Newlng. New York: Wley-Lss, nc., secton X, pp , Dahlstrand, C., Walden, M., Gersson, G. and Pettersson, S.: Transurethral mcrowave thermotherapy versus transurethral resecton for symptomatc bengn prostatc obstructon: a prospectve randomzed study wth a 2-year follow-up. Brt. J. UroL, 76: 614, EDTORAL COMMENT The authors ntroduce the results of a multcenter tral of hgh energy transurethral mcrowave thermo therapy. n ths regard the lower energy Prostasoft 2.0 software was altered. The power was ncreased to a maxmum of 70 watts compared to 60 watts, and rectal temperature safety thresholds were ncreased from 42.5 to 43.5C. Of

7 1 0 2 HGH ENERGY THERMOTHERAPY FOR BENGN PROSTATC HYPERPLASA 116 patents treated 67 were followed for 1 year. The overall magntude of response n terms of symptom scorng, peak flow rate and post-vod resdual seems to be superor to that obtaned wth the pror software (references 6, 8 to 10, 12 and 13 n artcle). The authors attrbute the mproved results to a hgher energy delvered to the prostate, resultng n a wder zone of tssue destructon and subvescal cavtes n 37% of the patents. Thus, mprovement n mean peak flow rate changes at 12 months approached 5 cc per second wth a statstcally sgnfcant decrease n post-vod resdual and an ncrease n voded volume. However, symptomatc mprovement does not appear to be sgnfcantly dfferent than what can be acheved n symptom score wth the Prostasoft 2.0 software. The downsde to usng ths software, however, has been an ncrease n the morbdty of the procedure and prolonged retenton rate. These morbdtes reman substantally less than those of transurethral resecton, snce patents are treated on an outpatent bass wthout requrng general anesthesa, although lberal parenteral sedaton and analgesa were necessary. Consderable rrtatve vodng complants that perssted for up to 4 weeks after the procedure are remnscent of the experence wth laser prostatectomy. t s clear that transurethral mcrowave thermotherapy s developng ts role as an alternatve n the management of BPH. The nvestgators contnue to provde these data. A randomzed prospectve study wth ths large populaton of patents comparng Prostasoft versons 2.0 and 2.5 more clearly have placed the hgh energy treatment n ts proper perspectve. Whle t s apparent that symptomatc mprovement s substantally the same for both versons, s t necessary to ncrease morbdty to mprove urodynamc parameters? Does the creaton of a subvescal cavty result n a more durable treatment? These questons wll be answered as transurethral mcrowave thermo therapy contnues to ncrease ts role n the overall management of ths dsease. Mchael L. Blute Department of Urology Mayo Clnc Rochester, Mnnesota