|
| |
 |
|
| ORIGINAL ARTICLE |
|
| Year : 2021 | Volume
: 32
| Issue : 3 | Page : 125-131 |
|
Effect of short-term preoperative dutasteride and finasteride on bleeding after transurethral resection of the prostate: A prospective randomized study
Nitesh Kumar, Sunil K Palve, Karthik Marripeddi, Sanath Thantla
Department of Urology, Osmania Medical College, Hyderabad, Telangana, India
| Date of Submission | 02-Jan-2021 |
| Date of Decision | 15-Mar-2021 |
| Date of Acceptance | 19-Mar-2021 |
| Date of Web Publication | 28-Sep-2021 |
Correspondence Address:
Nitesh Kumar
Room No: 504, Old Men's Hostel, Osmania Medical College, Koti, Hyderabad - 500 095, Telangana
India
 Source of Support: None, Conflict of Interest: None
DOI: 10.4103/UROS.UROS_2_21
Purpose: Transurethral resection of the prostate (TURP) is the standard surgical treatment for patients with benign prostatic hyperplasia (BPH). Among the many complications of TURP, the most prevalent and serious complication is hemorrhage. The aim of the study was to compare the effect of short-term (2–4 weeks) pretreatment of BPH with dutasteride and finasteride on bleeding after TURP. Methods: A prospective randomized double-blinded study was conducted in Osmania General Hospital, a tertiary care center for a period of 2 years. Two hundred and forty patients who were planned for TURP were included and randomized into four groups; D2: 2 weeks of dutasteride, F2: 2 weeks of finasteride, P2: 2 weeks of placebo, and D4: 4 weeks of dutasteride. The primary outcome was to evaluate the volume of blood loss. Results: The baseline variables were comparable among the groups. Statistically significant differences were seen in total volume of blood loss (183.4 vs. 172.7 vs. 288.5 vs. 173.2 ml, P = 0.01), blood loss per minute of operating time (3.80 vs. 3.65 vs. 5.71 vs. 3.61 ml/min, P = 0.02), and blood loss per gram of resected prostatic tissue (7.61 vs. 7.43 vs. 11.57 vs. 7.21 ml/g, P = 0.008). Blood transfusion requirement was significantly more in the placebo group (11.8%) compared to other groups (P = 0.02). Conclusion: Short-term preoperative dutasteride and finasteride for 2 weeks are equally effective, and they significantly reduce the perioperative blood loss during TURP. Four weeks of dutasteride has no significant advantage when compared to its 2-week course.
Keywords: Blood loss, dutasteride, finasteride, prostate, transurethral resection of the prostate
How to cite this article:
Kumar N, Palve SK, Marripeddi K, Thantla S. Effect of short-term preoperative dutasteride and finasteride on bleeding after transurethral resection of the prostate: A prospective randomized study. Urol Sci 2021;32:125-31 |
How to cite this URL:
Kumar N, Palve SK, Marripeddi K, Thantla S. Effect of short-term preoperative dutasteride and finasteride on bleeding after transurethral resection of the prostate: A prospective randomized study. Urol Sci [serial online] 2021 [cited 2023 May 28];32:125-31. Available from: https://www.e-urol-sci.com/text.asp?2021/32/3/125/326933 |
| Introduction | |  |
Transurethral resection of the prostate (TURP) is the standard surgical treatment for patients who have benign prostatic hyperplasia (BPH) but do not respond to medical management.[1] However, this procedure causes some complications, including perioperative bleeding, urinary incontinence, retrograde ejaculation, transurethral resection (TUR) syndrome, and erectile dysfunction. The combined morbidity rates of around 18% have been reported, and one of the most prevalent and serious complications is hemorrhage.[2],[3] It can lead to clot retention and blood transfusions, thereby prolonging hospital stay and re-interventions.[3] A perioperative blood loss of >1 l in 13% of patients has been documented.[4]
Five-alpha-reductase inhibitors (5-ARIs), along with alpha-blockers, have been approved for the medical treatment of BPH. 5-ARIs inhibit the conversion of testosterone (T) to its active form dihydrotestosterone (DHT) as catalyzed by five-alpha-reductase (5-AR).[5] The available 5-ARIs, namely finasteride and dutasteride, suppress DHT levels, prostate vascularity, and growth. Several studies have shown that pretreatment with finasteride has resulted in decreased blood loss during TURP[6],[7],[8] and reduced microvessel density (MVD) in the prostatic urothelium and stroma[9] and vascular endothelial growth factor (VEGF).[10] However, few studies have caused no effect.[11] Studies on dutasteride have mixed results; for example, some studies have supported its use that is similar to that of finasteride.[12],[13] Other studies have rejected its use.[11],[14] Color Doppler sonography (CDS) has also been applied to examine the changes in the vascularity of the prostate.[15]
Finasteride inhibits only type I 5-AR, whereas dutasteride blocks both types I and II 5-ARs.[11] Dutasteride results in higher suppression of serum DHT (>90% vs. 70%) but similarly suppresses intraprostatic DHT (85%–90%).[16],[17] The pharmacokinetics of both drugs are similar except that dutasteride has a longer half-life of 4–5 weeks than that of finasteride (6 h).[16] Therefore, if the less potent finasteride can decrease bleeding in TURP, dutasteride should cause the same effect. However, the reason for these different outcomes is unknown.
This study was conducted to compare the effect of the short-term pretreatment (2–4 weeks) of BPH with dutasteride and finasteride on bleeding after TURP. To our knowledge, this study was the first to compare 2 weeks of preoperative finasteride and placebo with 2 and 4 weeks of preoperative dutasteride.
| Methods | | |
A prospective randomized double-blinded study was conducted in Osmania General Hospital, a tertiary care center from January 2018 to December 2019. Ethical committee approval (No. 17618001013D, 2018) was obtained from Osmania Medical College before the study was conducted in accordance with the Declaration of Helsinki. All patients presenting with lower urinary tract symptoms that indicated an enlarged prostate were evaluated further with international prostate symptom score, digital rectal examination, uroflowmetry, serum prostate-specific antigen (PSA), and abdominal and transrectal ultrasonography of the prostate volume. A urodynamic study was performed if necessary. All the diagnosed BPH cases scheduled for surgery were included in the study and treated with alpha-blockers before they were included in the study. A detailed history, physical examination, and basic preoperative blood and urine investigations were carried out.
Patients were excluded from the study in accordance with the following criteria: they had a history of treatment with 5-ARIs within a year, prostate volume <30 g, previous invasive procedures of the prostate, pelvic or any other urological malignancies, anticoagulant use, hematological disorders, deranged renal function, severe hepatic dysfunction, and unstable cardiac disease. Urinary tract infections were treated before intervention, and malignancy was excluded via TRUS biopsy in patients with PSA >4 ng/dl. Nonsteroidal anti-inflammatory drugs (NSAIDs) and aspirin were discontinued 2 weeks before surgery and 1 week after surgery.
Written and informed consents were taken from the patients satisfying the inclusion and exclusion criteria. Patients were randomized into four groups by using a computer-generated randomization chart by a separate investigator, who had no role in result analysis. The patients were blinded to their respective study groups: Group 1, D2 with 0.5 mg of dutasteride for 14 days; Group 2, F2 with 5 mg of finasteride for 14 days; Group 3, P2 with placebo (empty capsules) for 14 days; and Group 4, D4 with 0.5 mg of dutasteride for 28 days. All the treatments were given once daily before TURP. After 2 weeks, the patients in the D2, P2, and F2 groups were subjected to TURP, and the patients in the D4 group were given medication for 2 more weeks.
All the patients under spinal anesthesia were subjected to TURP with 26 French Iglesias continuous irrigation resectoscope sheaths (Karl Storz) with a bipolar working element and normal saline (NS) irrigation. The operating surgeons had similar skills and were blinded to the treatment group. The irrigation fluid was collected in a bucket, where 1000 U heparin was added to prevent blood from clotting. After the procedure was completed, the bucket was stirred manually. Two samples (5 ml) were taken from the periphery of the bucket and transferred to a vial for hemoglobin estimation. A low hemoglobin-measuring system (HemoCue AB) was used to determine the hemoglobin concentration of the irrigating fluid in high precision.[4] The hemoglobin concentration (gm/dl) of the irrigation fluid was multiplied by the total volume of the irrigation (dL) used to determine the amount of intraoperative blood loss. Then, the obtained result was divided by the value of hemoglobin obtained before surgery to determine the amount of the total blood loss. Serum hemoglobin levels were measured before and 24 h after the procedure. The resected prostatic chips were weighed.
A 20-French 3-way Foley catheter was placed with a bulb inflated to 30 ml, and NS irrigation was continued postoperatively until hematuria subsided. Catheter traction was applied to all the patients and released after 6 h. The catheter was removed on day 2, and a voiding trial was conducted. Blood transfusion was given only when hemoglobin was < 9 gm/dl. Dutasteride or finasteride and placebo drugs were stopped in the postoperative period.
Outcome parameters were recorded by another surgeon who was also blinded to the study groups. Primary outcomes were as follows: duration of surgery, amount of irrigation fluid used, duration of postoperative irrigation, weight of the resected tissue, total volume of blood loss, blood loss per minute of operative time, and blood loss per gram of the resected prostate tissue. Secondary outcomes were as follows: decrease in serum hemoglobin, reduction in hematocrit after 24 h, blood transfusion requirement, and hospital stay length. All cases were histopathologically analyzed, and diagnosis other than BPH was excluded.
Sample size was calculated on the basis of power calculations previously described by Kim et al.[18] to determine the benefits of preoperative dutasteride in terms of reducing blood loss after TURP. The sample size of each treatment group was 40 patients, with >90% power to detect the differences through pair-wise comparison for the primary end point (blood loss in TURP) and around >80% power to identify the differences in secondary end points. At least 40 patients were included in each group; at the end of the 2-year study, 60 patients were included in each group. Data were analyzed with XLSTAT 2019.1 by (Addinsoft), The leading data analysis and statistical solution for microsoft excel®. One-way ANOVA and Fisher's exact test were performed for continuous and categorical data, respectively. A post hoc comparison test was used for intergroup comparison with adjustments for multiple comparisons by using the Bonferroni method. Data with P < 0.05 were considered statistically significant.
| Results | | |
Of the 324 patients who had symptoms of BPH and underwent TURP, 84 were excluded. The 240 remaining patients were randomized and allocated in four groups (60 patients in each group). Furthermore, five patients did not take the medications as specified, and four patients were lost during the study. The case flow during the study is summarized in [Figure 1].
The demographic data and the baseline parameters of the four study groups are shown in [Table 1]. The D2, F2, P2, and D4 groups had 58, 57, 59, and 57 patients, respectively. The mean age and body mass index (BMI) of the four groups were similar. Body composition was assessed in terms of BMI. The other baseline variables were comparable among the groups [Table 1]. | Table 1: Demographic data and the baseline parameters of different study groups
Click here to view |
The comparison of the primary outcomes of the study among the four groups is shown in [Table 2]. The duration of surgery, amount of irrigation fluid used, weight of the resected tissue, and duration of postoperative irrigation were not significantly different. The total volume of blood loss (183.4 vs. 172.7 vs. 288.5 vs. 173.2 ml, P = 0.01), blood loss/minute of operating time (3.80 vs. 3.65 vs. 5.71 vs. 3.61 ml/min, P = 0.02), and blood loss/gram of the resected prostatic tissue (7.61 vs. 7.43 vs. 11.57 vs. 7.21 ml/g, P = 0.008) were significantly different. The parameters of the D2 group were slightly higher than that of the D4 group even for the larger glands (>60 g, 184.1 vs. 172.7, P = 0.20). However, the results were not significantly different.
The comparison of the secondary outcomes of the study among the four groups is presented in [Table 3]. Hemoglobin and hematocrit before TURP were comparable among the groups. The decrease in hemoglobin at 24 h (1.10 vs. 0.98 vs. 1.91 vs. 0.94 gm/dl, P = 0.001), a reduction in hematocrit at 24 h (3.37 vs. 3.32 vs. 6.46 vs. 3.41, P = 0.001), and hemoglobin and hematocrit after TURP were significantly different. The P2 group required more blood transfusions (11.8%) than the other groups did (3.4%, 1.75%, and 1.75%, P = 0.02). The postoperative hospital stay among the groups did not significantly differ (P = 0.69).
The intergroup comparisons of the significant parameters are represented in [Table 2] and [Table 3]. The total volume of blood loss, blood loss per minute of operating time, blood loss per gram of the resected tissue, decrease in hemoglobin, reduction in hematocrit at 24 h, and requirement of blood transfusion in D2, F2, and D4 groups were significantly less than those in the P2 group. The D2, F2, D4, and D2 groups had no significant differences.
The drugs were well tolerated, and no severe adverse effects were observed in the study. The four groups were comparable in terms of the other clinical outcomes such as postoperative uroflometry, postvoid residual urine, postoperative TURP incontinence, and prolonged indwelling catheters. Few minor complications (Clavien Classes I and II) were observed, but no differences were found among the four groups. No major TURP-related complications (Clavien Classes III and IV) occurred.
| Discussion | | |
This study was primarily conducted to assess the effect of short-term preoperative dutasteride and finasteride on bleeding after TURP in men with BPH. The amount of blood loss significantly decreased during the perioperative period when the patients had 2 weeks of preoperative dutasteride or finasteride compared with that of placebo. Only a marginal insignificant benefit was detected after the duration of dutasteride was extended to 4 weeks. The secondary outcomes, namely hemoglobin, hematocrit, and blood transfusion, were also significantly reduced.
TURP is the standard surgical treatment of BPH,[1] but it is associated with several complications and associated morbidity (reaching 18%).[2],[3] Perioperative bleeding is the most frequent and serious complication and can lead to clot retention and need for blood transfusion (4.4% in a meta-analysis).[19] The perioperative blood loss of >1 l has also been observed in 13% of patients in other studies.[4],[5],[6],[7],[8],[9] However, a blood loss of around 250–500 ml in TURP without preoperative 5-ARIs has been reported in recent studies.[11],[12] The incidence of TUR syndrome decreases because of the use of bipolar TURP in NS.[3] In our study, all the cases were subjected to bipolar TURP in NS.
The rationale for the use of 5-ARIs before TURP comes from their ability to reduce the intraprostatic DTH concentration, which leads to decreased levels of androgen-derived growth factors required for angiogenesis. Ultimately, the vascularity of the prostate decreases as the MVD reduces, resulting in a reduction in blood loss.[10],[15],[20],[21] Kravchick et al.[15] reported decreased vascularity of the prostate by counting the discrete color Doppler signal (CD spot) of the prostate after the treatment with 5-ARIs. However, the routine preoperative use of 5-ARIs is not accepted worldwide because of conflicting results. Few studies have supported the administration of finasteride only[6],[7],[8],[9],[10],[14] and both 5-ARIs.[12],[13] Similarly, some studies have rejected both 5-ARIs[11] because of their role in reducing blood loss. According to a survey based in the United Kingdom, 98% of urologists used 5-ARIs for the treatment of hematuria of prostatic origin, but only 4% administered it before TURP.[22]
The optimal duration of preoperative 5-ARIs to reduce bleeding is diverse, ranging from 2 weeks to 3 months.[23] Donohue et al.[7],[22] reported that 2 weeks of preoperative finasteride results in significantly lower MVD and VEGF expression levels. This result provides evidence that the changes required to reduce bleeding are achieved early within 2 weeks. Carlin et al.[24] reported that gross hematuria caused by BPH subsides after the treatment with 2 weeks of finasteride. Kearney et al.[25] showed that patients who had BPH and began finasteride while actively bleeding had an average time to clear urine of 12 days (range of 2–45 days); this finding is related to prostatic volume (12.7 days for 40 g ≥10.3 days for 40–100 g). The clinical effect of the drug occurs within 2 weeks even for the glands up to 100 g. Hahn et al.[11] did not find any differences in MVD after 2 and 4 weeks of dutasteride treatment. Therefore, the preoperative treatment duration was set to 2 weeks only. An additional arm of 4 weeks of dutasteride treatment was added because of its reported lower efficacy than that of finasteride.[12],[15],[23] A long-term treatment may also provide relief to some patients, so they no longer require surgery and leave only more vascular prostates; however, comparing them may yield erroneous results.[12],[13],[15],[18]
Blood loss is quantified with various methods, including a decrease in hemoglobin, hematocrit, and hemoglobin in irrigating fluid.[6],[12],[18] The most practical way is the measurement of hemoglobin in the irrigating fluid.[11] A sensitive photometer (HemoCue AB) gives good results because of low hemoglobin levels present in the irrigating fluid. The speed of resection depending on a surgeon's experience and the amount of the resected tissue account for two-thirds of variability found in the perioperative blood loss.[4],[11] In our study, these variables were adjusted using the blood loss/gram of the resected prostatic tissue and each minute of operating time. A decrease in hemoglobin and hematocrit might not yield an accurate estimate of blood loss, but it was routinely used as a guide to monitor and determine the need for intervention.
In our study, the total volume of blood loss, blood loss/minute, and blood loss/gram were significantly higher in the P2 group than in the F2, D2, and D4 groups. The decrease in hemoglobin and hematocrit at 24 h and the need for blood transfusion were also significantly higher in the placebo group than in the other groups. When intergroup comparisons were performed, no significant differences were observed among D2, D4, and F2 groups. The efficacy of dutasteride is similar to that of finasteride in terms of reducing blood loss. Therefore, dutasteride should be regularly used because it is the most commonly used drug for medical management in combination therapy. Furthermore, the prolonged duration of 5-ARIs does not significantly affect the transfusion rates.
Our results are consistent with those reported in the literature. Bansal and Arora[12] (n = 450) reported significant reduction in blood loss by 4 weeks of finasteride and dutasteride compared with that of placebo. Kim et al.[18] (n = 83) obtained a lower mean blood loss after 2 weeks of dutasteride compared with that of placebo (ΔHb = 1.16 vs. 1.86; ΔHct = 3.69% vs. 5.39%; in our study, D2 vs. P2: ΔHb = 1.10 vs. 1.91; ΔHct = 5.8% vs. 7.8%). Liu et al.[8] (n = 100) found that the levels of VEGF expression and angiogenesis in the prostate decreased and blood loss reduced during TURP (135.8 vs. 245.1 ml; our study: P2: 172.7 vs. F2: 288.5 ml) after the pretreatment with 2 weeks of finasteride compared with that of placebo.
Various other studies have demonstrated that the preoperative use of 5-ARIs has no significant benefits.[12] Tuncel et al.[26] (n = 75) concluded that 5 weeks of dutasteride does not affect blood loss and MVD. Lund et al. [27] (n = 35) and Sandfeldt et al.[28] (n = 60) concluded that 3 months of preoperative finasteride has no effect on blood loss. However, both studies were underpowered. Hahn et al.[11] (n = 214) did not find a reduction in the MVD of prostatic tissue even after 4 months of dutasteride therapy; nevertheless, they achieved ~ 90% reduction in the serum and DHT concentrations, which are contradictory to a large study on 450 patients by Bansal and Arora.[12]
The MVD has a strong positive correlation with blood loss, and almost all studies demonstrating a reduction in blood loss after preoperative 5-ARIs showed that MVD counts in the resected tissue decreases.[9],[11],[12],[13] Häggström et al.[10] did not find any reduction in the human prostate MVD even after 3 months of treatment with finasteride. This finding might be due to the simultaneous shrinking of the gland and MVD, so density was unaffected. However, few questions about the use of MVD remained unanswered. Therefore, only the direct clinical effect of 5-ARIs, not MVD, was evaluated.
Few meta-analyses and systematic reviews regarding the role of preoperative treatment with 5-ARIs have been performed.[14],[22] Zong et al.[14] carried out a systematic review (n = 1156) involving 10 randomized controlled trials (RCTs) for finasteride and 5 RCTs for dutasteride. Preoperative finasteride treatment decreases MVD in resected prostate specimens and reduces blood loss. Dutasteride had no effect on bleeding. Zhu et al.[23] conducted a meta-analysis on 17 RCTs (n = 1489). They reported that finasteride but not dutasteride positively affects the reduction of blood loss and MVD. Ren et al.[29] conducted a systematic review on five RCTs and five cohort studies (n = 1022) and concluded that preoperative treatment with dutasteride can reduce surgical bleeding during TURP. The studies included in the meta-analysis varied, and a well-designed multicenter randomized placebo-controlled study with different treatment durations should be performed.
In this study, the role of short-term 5-ARIs in reducing bleeding in TURP was examined with a well-designed randomized placebo-controlled study. The clinical effect was set as the main outcome criterion, and a relatively large number of patients were included. This study was the first to compare 2 weeks of preoperative dutasteride and finasteride with placebo in preventing blood loss with an additional comparison arm of 4 weeks of dutasteride. This study was limited by indirect methods to predict blood loss. For instance, MVD, VEGF, and CDS were not used.
| Conclusion | | |
Short-term preoperative dutasteride and finasteride for 2 weeks are equally effective. They significantly reduce the perioperative blood loss during TURP. Dutasteride for 4 weeks has no significant advantage over its 2-week course. Therefore, the short-term (2 weeks) administration of 5-ARIs before TURP may reduce blood loss, minimize the related complications, and decrease the need for transfusion in the perioperative period.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
| References | | |
| 1. | Reich O, Seitz M, Gratzke C, Schlenker B, Walther S, Stief C. Benign prostatic hyperplasia (BPH): Surgical therapy options. Urologe A 2010;49:113-26.  |
| 2. | Rassweiler J, Teber D, Kuntz R, Hofmann R. Complications of transurethral resection of the prostate (TURP) – Incidence, management, and prevention. Eur Urol 2006;50:969-79. |
| 3. | Mebust WK, Holtgrewe HL, Cockett AT, Peters PC. Transurethral prostatectomy: Immediate and postoperative complications. Cooperative study of 13 participating institutions evaluating 3,885 patients. J Urol 1989;141:243-47. |
| 4. | Ekengren J, Hahn RG. Blood loss during transurethral resection of the prostate as measured by the HemoCue photometer. Scand J Urol Nephrol 1993;27:501-7. |
| 5. | Lepor H. Medical treatment of benign prostatic hyperplasia. Rev Urol 2011;13:20-33. |
| 6. | Hagerty JA, Ginsberg PC, Harmon JD, Harkaway RC. Pretreatment with finasteride decreases perioperative bleeding associated with transurethral resection of the prostate. Urology 2000;55:684-9. |
| 7. | Donohue JF, Hayne D, Karnik U, Thomas DR, Foster MC. Randomized, placebod with transurethral resection of the pros reduces prostatic vascularity rapidly within 2 weeks. BJU Int 2005;96:1319-22. |
| 8. | Liu XD, Yang YR, Lu YP, Zhang XH, Li FY, Wei Q. Preoperative finasteride on decreasing operative bleeding during transurethral resection of prostate. Chin J Urol 2003;24:694. |
| 9. | Pareek G, Shevchuk M, Armenakas NA, Vasovic L, Hochberg DA, Basillote JB, et al. The effect of finasteride on the expression of vascular endothelial growth factor and microvessel density: A possible mechanism for decreased prostatic bleeding in treated patients. J Urol 2003;169:20-3. |
| 10. | Häggström S, Tørring N, Møller K, Jensen E, Lund L, Nielsen JE, et al. Effects of finasteride on vascular endothelial growth factor. Scand J Urol Nephrol 2002;36:182-7. |
| 11. | Hahn RG, Fagerström T, Tammela TL, Van Vierssen Trip O, Beisland HO, Duggan A, et al. Blood loss and postoperative complications associated with transurethral resection of the prostate after pretreatment with dutasteride. BJU Int 2007;99:587-94. |
| 12. | Bansal A, Arora A. Transurethral resection of prostate and bleeding: A prospective, randomized, double-blind placebo-controlled trial to see the efficacy of short-term use of finasteride and dutasteride on operative blood loss and prostatic microvessel density. J Endourol 2017;31:910-7. |
| 13. | Woo JH, Kang JY, Kim EK, Yoo TK. The effect of short term dutasteride therapy on microvessel density in benign prostatic hyperplasia. Korean J Urol 2008;49:515-9. |
| 14. | Zong HT, Peng XX, Yang CC, Zhang Y. A systematic review of the effects and mechanisms of preoperative 5α-reductase inhibitors on intraoperative haemorrhage during surgery for benign prostatic hyperplasia. Asian J Androl 2011;13:812-8. |
| 15. | Kravchick S, Cytron S, Mamonov A, Peled R, Linov L. Effect of short-term dutasteride therapy on prostate vascularity in patients with benign prostatic hyperplasia: A pilot study. Urology 2009;73:1274-8. |
| 16. | Bartsch G, Rittmaster RS, Klocker H. Dihydrotestosterone and the concept of 5alpha-reductase inhibition in human benign prostatic hyperplasia. Eur Urol 2000;37:367-80. |
| 17. | Roehrborn C, Andriole G, Schalken J, Wilson T, Clark R. Dutasteride, a novel dual 5-A reductase inhibitor, reduces serum DHT to a greater extent versus finasteride and achieves finasteride maximal reduction in a larger proportion of patients. Eur Urol Suppl 2003;2:161. |
| 18. | Kim KS, Jeong WS, Park SY, Kim YT, Moon HS. The effect of two weeks of treatment with dutasteride on bleeding after transurethral resection of the prostate. World J Mens Health 2015;33:14-9. |
| 19. | Mayer EK, Kroeze SG, Chopra S, Bottle A, Patel A. Examining the 'gold standard': A comparative critical analysis of three consecutive decades of monopolar transurethral resection of the prostate (TURP) outcomes. BJU Int 2012;110:1595-601 |
| 20. | Lekås E, Bergh A, Damber JE. Effects of finasteride and bicalutamide on prostatic blood flow in the rat. BJU Int 2000;85:962-5. |
| 21. | Aboumarzouk OM, Aslam MZ, Wedderburn A, Turner K, Hughes O, Kynaston HG. Should finasteride be routinely given preoperatively for TURP? ISRN Urol 2013;2013:458353. |
| 22. | Donohue JF, Barber NJ. How do we investigate haematuria and what role has finasteride? BJU Int 2004;93:3-4. |
| 23. | Zhu YP, Dai B, Zhang HL, Shi GH, Ye DW. Impact of preoperative 5α-reductase inhibitors on perioperative blood loss in patients with benign prostatic hyperplasia: A meta-analysis of randomized controlled trials. BMC Urol 2015;15:47. |
| 24. | Carlin BI, Bodner DR, Spirnak JP, Resnick MI. Role of finasteride in the treatment of recurrent hematuria secondary to benign prostatic hyperplasia. Prostate 1997;31:180-2. |
| 25. | Kearney MC, Bingham J, Bergland R, Meade-D'Alisera P, Puchner PJ. Clinical predictors in the use of finasteride for control of gross hematuria due to benign prostatic hyperplasia. J Urol 2002;167:2489-91. |
| 26. | Tuncel A, Ener K, Han O, Nalcacioglu V, Aydin O, Seckin S, et al. Effects of short-term dutasteride and Serenoa repens on perioperative bleeding and microvessel density in patients undergoing transurethral resection of the prostate. Scand J Urol Nephrol 2009;43:377-82. |
| 27. | Lund L, Møller Ernst-Jensen K, Tørring N, Erik Nielsen J. Impact of finasteride treatment on perioperative bleeding before transurethral resection of the prostate: A prospective randomized study. Scand J Urol Nephrol 2005;39:160-2. |
| 28. | Sandfeldt L, Bailey DM, Hahn RG. Blood loss during transurethral resection of the prostate after 3 months of treatment with finasteride. Urology 2001;58:972-6. |
| 29. | Ren J, Lai S, Jiang Z, Xu X, Diao T, Thiruchelvam N, et al. A systematic review and meta-analysis of the effects on dutasteride treatment for reducing surgical blood loss during transurethral resection of the prostate. Urol Int 2017;98:456-65. |
[Figure 1]
[Table 1], [Table 2], [Table 3]
|
Search Pubmed for