human
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND The Early Intervention Study , a placebo-controlled clinical trial , enrolled approximately 200 patients between age 45 - 65 years who had mild symptoms associated with early benign hyperplasia ( BPH ) . Prostate volume was measured by magnetic resonance imaging ( MRI ) and read by the local radiologist , who was blinded to the treatment group but not to the sequence of MRI scans . In order to ascertain whether knowledge of the sequence of the MRI scans by the local radiologist was introducing bias in prostate volume changes , a single radiologist was selected to reread all MRI scans at the end of the study . METHODS Each film was masked as to patient identity , study drug , and date . A new r and omization schedule was prepared to blind the single reader to both sequence and treatment . The two sets of readings were compared . RESULTS Accuracy was dramatically improved when defined as percentage of patients with a 20 % or more decrease in prostate volume , from 14 % to 0 % in placebo patients , and from 38 % to 29 % in finasteride patients . The variability was significantly reduced ( by 50 % ) when read by a single observer [ 1 ] . CONCLUSIONS A single reader , blinded to time sequence as well as to therapy , improves the accuracy and precision of the measurements when compared to multiple readers , blinded only to drug therapy A group of 69 men with bladder outflow obstruction due to benign prostatic hyperplasia ( BPH ) were treated in a double-blind , placebo-controlled study with finasteride ( Proscar , MK-906 ) , a 5-alpha reductase inhibitor , 5 mg or 10 mg/day or placebo for 3 months ; subsequently , 20 patients received finasteride 5 mg/day for a further 9 months in an open extension study . In treated patients dihydrotestosterone declined by over 60 % , remaining unchanged with placebo . Symptom scores fell significantly in all 3 groups . Mean maximum flow rates fell slightly in placebo-treated patients but improved by 1.5 ml/s in the 10 mg group and by 3.3 ml/s in the 5 mg group . After 1 year 's treatment , the reduction in symptom score and increase in flow rate were well maintained ; the mean prostate volume was reduced by 14 % and prostatic specific antigen declined by 28 % . It was concluded that finasteride shows some efficacy in the treatment of BPH , with minimal toxicity , but 12 months of therapy or longer may be necessary to achieve maximal effect The clinical effects of finasteride , a 5 alpha-reductase inhibitor , in patients with benign prostatic hyperplasia ( BPH ) were evaluated in a double-blind , placebo-controlled study . Forty-six patients with symptomatic BPH were r and omly assigned to 2 groups , the finasteride group and the placebo group . The finasteride group received 5 mg of finasteride daily for 6 months . Prostate volume , urinary flow , urinary symptoms , serum prostate-specific antigen ( PSA ) and adverse events were determined before and after treatment . After 6 months of treatment the patients treated with 5 mg of finasteride per day had a 30 % decrease in their total urinary symptom score , a 14 % decrease in prostate volume and a 0.9 ng/dL decrease of PSA . Their maximal urinary flow rate increased by 1.42 mL per second and the mean urinary flow rate increased by 0.64 mL per second . The patients given placebo showed no significant changes in their prostate volume , serum PSA and maximal and mean urinary flow rate . However , the symptom scores in the placebo group also decreased significantly . When compared with the placebo group , those in the finasteride group had significantly lower prostate volume , serum PSA , maximal urinary flow rate and urinary symptoms , but not mean urinary flow rate . The frequency of adverse events was low in both the finasteride and placebo groups . These results show that finasteride may be an effective and safe alternative for the treatment of patients with BPH Objective To test the hypothesis that in patients with benign prostatic hyperplasia ( BPH ) , the outcome of drug therapy with finasteride may be predictable from the baseline prostate volume and that positive clinical effects might be expected only in patients with prostate volumes of > 40 mL , using a subgroup analysis of results from a previously reported clinical trial of finasteride and phytotherapy We assessed the long-term safety and efficacy of finasteride , an orally active 5 alpha-reductase inhibitor , in 2 previously reported groups of patients with symptomatic benign prostatic hyperplasia ( BPH ) . Prostate volume was measured by magnetic resonance imaging , and the maximum urinary flow rate was assessed noninvasively . Symptoms were scored utilizing a patient self-administered symptom score question naire . Total symptom scores ranged from 0 ( or asymptomatic ) to 35 ( severely symptomatic ) . After an initial double-blind period , the patients in study 1 were treated with 10 mg finasteride for 1 year and then switched to 5 mg finasteride for an additional 4 years , whereas patients in study 2 were treated with 5 mg finasteride for the entire 5 years . A total of 190 patients were r and omized in the double-blind studies , 156 entered year 1 of the open extension and 70 patients completed 5 years of finasteride therapy . In both studies prostate volume was reduced from baseline by 30 % , dihydrotestosterone was reduced by 72 % , and the maximum urinary flow rate improved by approximately 1.5 ml/s . Prostate-specific antigen was decreased by approximately 50 % . Finasteride was well tolerated ; approximately 10 % of patients reported sexual adverse experiences during the 5-year study period , which were considered drug related by the investigators . The incidence in reporting sexual adverse experiences did not increase with the increased duration of treatment : findings consistent with previous reports . In summary treatment of BPH with finasteride for 5 years inhibits the progression of the disease with an excellent safety profile and represents a low-risk medical option for the treatment of symptomatic BPH In this multicentre , double-blind study , patients with LUTS/BPH were r and omised to 26 weeks with finasteride 5 mg once daily ( n=204 ) or tamsulosin 0.4 mg once daily ( n=199 ) . Double-blind treatment was continued for another 26 weeks ( total treatment duration : 1 y ) . The primary efficacy parameter was the difference in mean change in total Symptom Problem Index ( SPI ) from baseline to end point at week-26 in the intention-to-treat ( ITT ) and per protocol ( PP ) population s. Tamsulosin induced a greater improvement in total SPI ( −5.2 points or −37 % ) compared to finasteride ( −4.5 points or −31 % ) at week-26 ( P=0.055 in ITT and P=0.032 in PP ) . Tamsulosin  improved urinary symptoms ( particularly the more bothersome storage symptoms ) and flow more quickly than finasteride . The difference was statistically significant for the SPI from week-1 ( reduction , respectively , −2.5 vs −1.8 points , P=0.043 ) to week-18 and for Qmax from week-1 ( increase , respectively , 2.3 vs 0.7 ml/s , P=0.0007 ) to week-12 . Both treatments were well tolerated with a comparable incidence of adverse events , including urinary retention We studied the effects of 5 alpha-reductase inhibitor ( finasteride ) in the treatment of benign prostatic hyperplasia ( BPH ) . This study is a r and omized controlled trial . Sixty-two patients were treated with 5 alpha-reductase ( finasteride 5 mg/day ) and 61 patients  ( control group )  with placebo for one year . Prostatic volume , maximal urine flow rate , AUA symptom scoring , residual urine volume and prostate-specific antigen ( PSA ) levels were evaluated at 3 , 6 , 9 and 12 months . In the first 6 months prostatic volume decreased rapidly ( 20.5 % ) , in the second 6 months it decreased slowly and reached the maximal rate ( 23.3 % ) . Maximal urine flow rate increased in the second 6 months . AUA symptom scores decreased first at 3 months and were 4.6 points lower at the end of the 12th month . There were no significant changes in residual volume . The 5 alpha-reductase inhibitor caused a 50 % decrease in PSA levels , like in other studies .Becuase of the prolonged use of the drug , treatment with 5 alpha-reductase inhibitor is not tolerated by many patients and being expensive its future in the pharmacotherapy of BPH is unclear The purpose of this paper is to examine effects of finasteride 5 mg across different age groups in an ethnically diverse population of men with symptomatic benign prostatic hyperplasia ( BPH ) seen in community urology and primary care practice s. Data were combined from two previous placebo-controlled r and omised trials of finasteride that evaluated changes in urinary symptoms , blinded global assessment s of urologic status , adverse experiences , and effects on dihydrotestosterone ( DHT ) and prostate-specific antigen ( PSA ) in over 4500 men .  Finasteride showed a favourable efficacy and tolerability profile in this large ethnically diverse population and was similarly effective in middle-aged and older men with BPH and prostate gl and enlargement PURPOSE We evaluated the effectiveness of single or combination drug therapy on nocturia in men with lower urinary tract symptoms suggestive of benign prostatic hyperplasia . MATERIAL S AND METHODS A total of 3,047 men with lower urinary tract symptoms/benign prostatic hyperplasia enrolled in the Medical Therapy of Prostatic Symptoms trial were r and omly assigned to receive doxazosin alone , finasteride alone , combination therapy or placebo . Treatment effectiveness was assessed according to intent to treat by mean reduction in self-reported nightly nocturia at 1 and 4 years . A subgroup analysis by age ( younger than 70 vs 70 years old or older ) was also performed . RESULTS Of the men 2,583 reported 1 or more episodes of nocturia and finished 12 or more months of the trial .  Mean nocturia was similar in all groups at baseline . Mean nocturia was reduced at 1 year by 0.35 , 0.40 , 0.54 and 0.58 in the placebo , finasteride , doxazosin and combination groups , respectively . Reductions with doxazosin and combination therapy were statistically greater than with placebo ( p < 0.05 ) . At 4 years nocturia was also significantly reduced in patients treated with doxazosin and combination therapy ( p < 0.05 vs placebo ) . In men older than 70 years ( 495 ) all drugs significantly reduced nocturia at 1 year ( finasteride 0.29 , doxazosin 0.46 and combination 0.42 ) compared to placebo ( 0.11 , p < 0.05 ) . CONCLUSIONS Doxazosin and combination therapy reduced nocturia more than placebo , but the net benefit of active drug compared to placebo was often modest with a net difference of less than 0.20 fewer nightly nocturia episodes at 1 and 4 years . Findings in men 70 years old or older were similar , with an even smaller effect observed for finasteride OBJECTIVES To determine the long-term effects of finasteride treatment on prostate tissue composition ; to relate these effects to clinical outcomes ; and to test the hypothesis that finasteride exerts a selective or preferential action on the transition zone . METHODS Nineteen men with symptomatic benign prostatic hyperplasia ( BPH ) who completed a 6-month double-blind trial of finasteride  were enrolled in a 24-month open-label extension study of drug responders . Magnetic resonance imaging and prostate biopsy for morphometric analysis were performed together 70 times : at baseline ( n = 19 ) , after treatment periods of intermediate duration ( 6 to 18 months , n = 32 ) , and after long-term drug treatment ( 24 to 30 months , n = 19 ) . At baseline , prostate volume averaged 51 cc , of which 57 % was transition zone . RESULTS Decreases in symptom score , dihydrotestosterone and prostate-specific antigen levels , and prostate volume occurred at 6 months ( P < 0.01 ) , stabilized , and were maintained without further long-term decreases . Prostate epithelium contracted progressively from baseline ( 19.2 % tissue composition ; 6.0-cc volume ; 3.2 stroma/epithelial ratio ) to intermediate ( 12.5 % , 3.3 cc , and 5.6 , respectively ) to long-term treatment ( 6.4 % , 2.0 cc , and 17.4 , respectively , P < 0.01 for all ) . Percent epithelial contraction was similar in the peripheral and transition zones ( P = NS ) . The transition zone remained a relatively constant proportion ( 53 % to 58 % ) of whole-prostate volume from baseline to long-term observation . CONCLUSIONS Long-term finasteride treatment ( 24 to 30 months ) results in a marked involution of the prostate epithelium , which continues to progress for many months after clinical effects stabilize . The effect on the epithelium is similar in the peripheral and transition zones for both morphometric and volumetric changes . Progressive contraction of the prostate epithelium appears to constitute the underlying mechanism for sustained action of finasteride This study sought to assess the efficacy , tolerability , and effect of finasteride on health-related quality of life ( HRQL ) in a diverse population of men with moderate-to-severe symptomatic benign prostatic hyperplasia ( BPH ) . This double-blind study evaluated finasteride and 
    Output:
    
agent
MAIN RESULTS Finasteride consistently improved urinary symptom scores more than placebo in trials of > 1 year duration , and significantly lowered the risk of BPH progression ( acute urinary retention , risk of surgical intervention , ≥ 4 point increase in the AUASI/IPSS ) .
In comparison to alpha-blocker monotherapy , finasteride was less effective than either doxazosin or terazosin , but equally effective compared to tamsulosin .
Both doxazosin and terazosin were significantly more likely than finasteride to improve peak urine flow and nocturia , versus finasteride .
Versus tamsulosin , peak urine flow and QoL improved equally well versus finasteride .
However , finasteride was associated with a lower risk of surgical intervention compared to doxazosin , but not to terazosin , while finasteride and doxazosin were no different for risk of acute urinary retention .
Finasteride + doxazosin and doxazosin monotherapy  improved urinary symptoms equally well ( ≥ 4 point improvement).For finasteride , there was an increased risk of ejaculation disorder , impotence , and lowered libido , versus placebo .
Versus doxazosin , finasteride had a lower risk of asthenia , dizziness , and postural hypotension , and versus terazosin , finasteride had a significant , lower risk of asthenia , dizziness , and postural hypotension .
Finasteride improves long-term urinary symptoms versus placebo , but is less effective than doxazosin .
Long-term combination therapy with alpha blockers ( doxazosin , terazosin ) improves symptoms significantly better than finasteride monotherapy .
Finasteride + doxazosin improves symptoms equally - and clinical ly - to doxazosin alone .
Finasteride + doxazosin versus doxazosin  improves scores equally for short and long term .
Drug-related adverse effects for finasteride are rare ; nevertheless , men  taking  finasteride are at increased risk for impotence , erectile dysfunction , decreased libido , and ejaculation disorder , versus placebo .
Versus doxazosin , which has higher rates of dizziness , postural hypotension , and asthenia , men taking finasteride are at increased risk for impotence , erectile dysfunction , decreased libido , and ejaculation disorder .
Finasteride significantly reduces asthenia , postural hypotension , and dizziness versus terazosin .
Finasteride significantly lowers the risk of asthenia , dizziness , ejaculation disorder , and postural hypotension , versus finasteride + terazosin
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND The Early Intervention Study , a placebo-controlled clinical trial , enrolled approximately 200 patients between age 45 - 65 years who had mild symptoms associated with early benign hyperplasia ( BPH ) . Prostate volume was measured by magnetic resonance imaging ( MRI ) and read by the local radiologist , who was blinded to the treatment group but not to the sequence of MRI scans . In order to ascertain whether knowledge of the sequence of the MRI scans by the local radiologist was introducing bias in prostate volume changes , a single radiologist was selected to reread all MRI scans at the end of the study . METHODS Each film was masked as to patient identity , study drug , and date . A new r and omization schedule was prepared to blind the single reader to both sequence and treatment . The two sets of readings were compared . RESULTS Accuracy was dramatically improved when defined as percentage of patients with a 20 % or more decrease in prostate volume , from 14 % to 0 % in placebo patients , and from 38 % to 29 % in finasteride patients . The variability was significantly reduced ( by 50 % ) when read by a single observer [ 1 ] . CONCLUSIONS A single reader , blinded to time sequence as well as to therapy , improves the accuracy and precision of the measurements when compared to multiple readers , blinded only to drug therapy A group of 69 men with bladder outflow obstruction due to benign prostatic hyperplasia ( BPH ) were treated in a double-blind , placebo-controlled study with finasteride ( Proscar , MK-906 ) , a 5-alpha reductase inhibitor , 5 mg or 10 mg/day or placebo for 3 months ; subsequently , 20 patients received finasteride 5 mg/day for a further 9 months in an open extension study . In treated patients dihydrotestosterone declined by over 60 % , remaining unchanged with placebo . Symptom scores fell significantly in all 3 groups . Mean maximum flow rates fell slightly in placebo-treated patients but improved by 1.5 ml/s in the 10 mg group and by 3.3 ml/s in the 5 mg group . After 1 year 's treatment , the reduction in symptom score and increase in flow rate were well maintained ; the mean prostate volume was reduced by 14 % and prostatic specific antigen declined by 28 % . It was concluded that finasteride shows some efficacy in the treatment of BPH , with minimal toxicity , but 12 months of therapy or longer may be necessary to achieve maximal effect The clinical effects of finasteride , a 5 alpha-reductase inhibitor , in patients with benign prostatic hyperplasia ( BPH ) were evaluated in a double-blind , placebo-controlled study . Forty-six patients with symptomatic BPH were r and omly assigned to 2 groups , the finasteride group and the placebo group . The finasteride group received 5 mg of finasteride daily for 6 months . Prostate volume , urinary flow , urinary symptoms , serum prostate-specific antigen ( PSA ) and adverse events were determined before and after treatment . After 6 months of treatment the patients treated with 5 mg of finasteride per day had a 30 % decrease in their total urinary symptom score , a 14 % decrease in prostate volume and a 0.9 ng/dL decrease of PSA . Their maximal urinary flow rate increased by 1.42 mL per second and the mean urinary flow rate increased by 0.64 mL per second . The patients given placebo showed no significant changes in their prostate volume , serum PSA and maximal and mean urinary flow rate . However , the symptom scores in the placebo group also decreased significantly . When compared with the placebo group , those in the finasteride group had significantly lower prostate volume , serum PSA , maximal urinary flow rate and urinary symptoms , but not mean urinary flow rate . The frequency of adverse events was low in both the finasteride and placebo groups . These results show that finasteride may be an effective and safe alternative for the treatment of patients with BPH Objective To test the hypothesis that in patients with benign prostatic hyperplasia ( BPH ) , the outcome of drug therapy with finasteride may be predictable from the baseline prostate volume and that positive clinical effects might be expected only in patients with prostate volumes of > 40 mL , using a subgroup analysis of results from a previously reported clinical trial of finasteride and phytotherapy We assessed the long-term safety and efficacy of finasteride , an orally active 5 alpha-reductase inhibitor , in 2 previously reported groups of patients with symptomatic benign prostatic hyperplasia ( BPH ) . Prostate volume was measured by magnetic resonance imaging , and the maximum urinary flow rate was assessed noninvasively . Symptoms were scored utilizing a patient self-administered symptom score question naire . Total symptom scores ranged from 0 ( or asymptomatic ) to 35 ( severely symptomatic ) . After an initial double-blind period , the patients in study 1 were treated with 10 mg finasteride for 1 year and then switched to 5 mg finasteride for an additional 4 years , whereas patients in study 2 were treated with 5 mg finasteride for the entire 5 years . A total of 190 patients were r and omized in the double-blind studies , 156 entered year 1 of the open extension and 70 patients completed 5 years of finasteride therapy . In both studies prostate volume was reduced from baseline by 30 % , dihydrotestosterone was reduced by 72 % , and the maximum urinary flow rate improved by approximately 1.5 ml/s . Prostate-specific antigen was decreased by approximately 50 % . Finasteride was well tolerated ; approximately 10 % of patients reported sexual adverse experiences during the 5-year study period , which were considered drug related by the investigators . The incidence in reporting sexual adverse experiences did not increase with the increased duration of treatment : findings consistent with previous reports . In summary treatment of BPH with finasteride for 5 years inhibits the progression of the disease with an excellent safety profile and represents a low-risk medical option for the treatment of symptomatic BPH In this multicentre , double-blind study , patients with LUTS/BPH were r and omised to 26 weeks with finasteride 5 mg once daily ( n=204 ) or tamsulosin 0.4 mg once daily ( n=199 ) . Double-blind treatment was continued for another 26 weeks ( total treatment duration : 1 y ) . The primary efficacy parameter was the difference in mean change in total Symptom Problem Index ( SPI ) from baseline to end point at week-26 in the intention-to-treat ( ITT ) and per protocol ( PP ) population s. Tamsulosin induced a greater improvement in total SPI ( −5.2 points or −37 % ) compared to finasteride ( −4.5 points or −31 % ) at week-26 ( P=0.055 in ITT and P=0.032 in PP ) . Tamsulosin  improved urinary symptoms ( particularly the more bothersome storage symptoms ) and flow more quickly than finasteride . The difference was statistically significant for the SPI from week-1 ( reduction , respectively , −2.5 vs −1.8 points , P=0.043 ) to week-18 and for Qmax from week-1 ( increase , respectively , 2.3 vs 0.7 ml/s , P=0.0007 ) to week-12 . Both treatments were well tolerated with a comparable incidence of adverse events , including urinary retention We studied the effects of 5 alpha-reductase inhibitor ( finasteride ) in the treatment of benign prostatic hyperplasia ( BPH ) . This study is a r and omized controlled trial . Sixty-two patients were treated with 5 alpha-reductase ( finasteride 5 mg/day ) and 61 patients  ( control group )  with placebo for one year . Prostatic volume , maximal urine flow rate , AUA symptom scoring , residual urine volume and prostate-specific antigen ( PSA ) levels were evaluated at 3 , 6 , 9 and 12 months . In the first 6 months prostatic volume decreased rapidly ( 20.5 % ) , in the second 6 months it decreased slowly and reached the maximal rate ( 23.3 % ) . Maximal urine flow rate increased in the second 6 months . AUA symptom scores decreased first at 3 months and were 4.6 points lower at the end of the 12th month . There were no significant changes in residual volume . The 5 alpha-reductase inhibitor caused a 50 % decrease in PSA levels , like in other studies .Becuase of the prolonged use of the drug , treatment with 5 alpha-reductase inhibitor is not tolerated by many patients and being expensive its future in the pharmacotherapy of BPH is unclear The purpose of this paper is to examine effects of finasteride 5 mg across different age groups in an ethnically diverse population of men with symptomatic benign prostatic hyperplasia ( BPH ) seen in community urology and primary care practice s. Data were combined from two previous placebo-controlled r and omised trials of finasteride that evaluated changes in urinary symptoms , blinded global assessment s of urologic status , adverse experiences , and effects on dihydrotestosterone ( DHT ) and prostate-specific antigen ( PSA ) in over 4500 men .  Finasteride showed a favourable efficacy and tolerability profile in this large ethnically diverse population and was similarly effective in middle-aged and older men with BPH and prostate gl and enlargement PURPOSE We evaluated the effectiveness of single or combination drug therapy on nocturia in men with lower urinary tract symptoms suggestive of benign prostatic hyperplasia . MATERIAL S AND METHODS A total of 3,047 men with lower urinary tract symptoms/benign prostatic hyperplasia enrolled in the Medical Therapy of Prostatic Symptoms trial were r and omly assigned to receive doxazosin alone , finasteride alone , combination therapy or placebo . Treatment effectiveness was assessed according to intent to treat by mean reduction in self-reported nightly nocturia at 1 and 4 years . A subgroup analysis by age ( younger than 70 vs 70 years old or older ) was also performed . RESULTS Of the men 2,583 reported 1 or more episodes of nocturia and finished 12 or more months of the trial .  Mean nocturia was similar in all groups at baseline . Mean nocturia was reduced at 1 year by 0.35 , 0.40 , 0.54 and 0.58 in the placebo , finasteride , doxazosin and combination groups , respectively . Reductions with doxazosin and combination therapy were statistically greater than with placebo ( p < 0.05 ) . At 4 years nocturia was also significantly reduced in patients treated with doxazosin and combination therapy ( p < 0.05 vs placebo ) . In men older than 70 years ( 495 ) all drugs significantly reduced nocturia at 1 year ( finasteride 0.29 , doxazosin 0.46 and combination 0.42 ) compared to placebo ( 0.11 , p < 0.05 ) . CONCLUSIONS Doxazosin and combination therapy reduced nocturia more than placebo , but the net benefit of active drug compared to placebo was often modest with a net difference of less than 0.20 fewer nightly nocturia episodes at 1 and 4 years . Findings in men 70 years old or older were similar , with an even smaller effect observed for finasteride OBJECTIVES To determine the long-term effects of finasteride treatment on prostate tissue composition ; to relate these effects to clinical outcomes ; and to test the hypothesis that finasteride exerts a selective or preferential action on the transition zone . METHODS Nineteen men with symptomatic benign prostatic hyperplasia ( BPH ) who completed a 6-month double-blind trial of finasteride  were enrolled in a 24-month open-label extension study of drug responders . Magnetic resonance imaging and prostate biopsy for morphometric analysis were performed together 70 times : at baseline ( n = 19 ) , after treatment periods of intermediate duration ( 6 to 18 months , n = 32 ) , and after long-term drug treatment ( 24 to 30 months , n = 19 ) . At baseline , prostate volume averaged 51 cc , of which 57 % was transition zone . RESULTS Decreases in symptom score , dihydrotestosterone and prostate-specific antigen levels , and prostate volume occurred at 6 months ( P < 0.01 ) , stabilized , and were maintained without further long-term decreases . Prostate epithelium contracted progressively from baseline ( 19.2 % tissue composition ; 6.0-cc volume ; 3.2 stroma/epithelial ratio ) to intermediate ( 12.5 % , 3.3 cc , and 5.6 , respectively ) to long-term treatment ( 6.4 % , 2.0 cc , and 17.4 , respectively , P < 0.01 for all ) . Percent epithelial contraction was similar in the peripheral and transition zones ( P = NS ) . The transition zone remained a relatively constant proportion ( 53 % to 58 % ) of whole-prostate volume from baseline to long-term observation . CONCLUSIONS Long-term finasteride treatment ( 24 to 30 months ) results in a marked involution of the prostate epithelium , which continues to progress for many months after clinical effects stabilize . The effect on the epithelium is similar in the peripheral and transition zones for both morphometric and volumetric changes . Progressive contraction of the prostate epithelium appears to constitute the underlying mechanism for sustained action of finasteride This study sought to assess the efficacy , tolerability , and effect of finasteride on health-related quality of life ( HRQL ) in a diverse population of men with moderate-to-severe symptomatic benign prostatic hyperplasia ( BPH ) . This double-blind study evaluated finasteride and 
    Output:
    