While new treatment options have emerged, transurethral resection of the prostate (TURP) remains the gold standard surgical intervention for benign prostatic hyperplasia (BPH) worldwide and is frequently used as a comparator for evaluating other procedures. However, we hypothesize that the safety and efficacy of TURP may have changed over the past two decades, and that the outcomes may vary across different regions of the world. Therefore, to gain a comprehensive understanding of these potential variations, we conducted a novel systematic review and meta-analysis of randomized-clinical-trials (RCT) to evaluate the outcomes of TURP across different continents and time periods during the 21st-century. Our goal is to identify possible trends in the effectiveness of this well-established treatment.

A PubMed search was conducted with keywords: transurethral resection of the prostate, benign prostatic hyperplasia, enlarged prostate, randomized clinical trial. We performed a review from January 1, 2000, until December 31, 2022. Only RCTs which compared TURP to other treatments were included. Excluded systematic review articles, meta-analyses, duplicate articles, irrelevant articles, case reports, expert opinion articles and commentaries. 126 articles with 8431 patients were selected for full text review. The selected articles were divided based on the continents of studies into 4 subgroups: Europe, Asia, Africa, and Others (Including North America, South America, and Australia. This was done due to the small number of studies from these continents). The articles were also divided based on 5 and one 8-year period as: 2000-2004, 2005-2009, 2010-2014, and 2015-2022. Information regarding the following outcomes was extracted: International Prostate Symptoms Score (IPSS), Maximum urine flow rate (Qmax), and Post-void residual (PVR). Information related to complications (incontinence, irritative symptoms, and Urinary retention) was also extracted. Data was extracted for time points at baseline, 3-months, 1-year, 3-years. The mean difference (MD) for change from baseline at each timepoint was calculated as an outcome measure for continuous variables and compared across all studies, and between subgroups of continents and time. The proportions of complication rates were imputed and compared. The heterogeneity was divided in low (<25%), moderate (25-75%), and high (>75%). Between subgroup heterogeneity was analyzed using the Qm statistic and p-value<0.05 was considered significant.

There was no significant difference in IPSS outcomes between continents. The overall heterogeneity (OH) between continents was consistently low. However, some continents (such as Africa) exhibited moderate heterogeneity within their subgroups. Meanwhile, there was no significant difference in IPSS outcomes between the 5-year subgroups at 3 months and 12 months. At 36 months, although there was no significant difference between the 5-year subgroups, the OH was high.  

For Qmax, there were significant differences in the heterogeneity between continents at different time points. At 3 months, there was high OH, but no significant difference between continents. However, within the continent subgroups, Europe had high heterogeneity, while Africa and Asia had moderate heterogeneity. At 12 months, there was a significant difference in the heterogeneity of Qmax outcomes between continents, with Europe having high heterogeneity, while Africa and Others having low heterogeneity. At 36 months, there was no significant difference in the heterogeneity of Qmax outcomes between continents, but the heterogeneity was high between studies from Europe. Looking to Qmax under 5-year group perspective, OH was high at 3 months, with 2010-2014 and 2015-2022 having high heterogeneity, while 2000-2004 and 2005-2009 had low to moderate heterogeneity. At 12 months, OH was high, but there was no significant difference in the heterogeneity of Qmax outcomes between 5-year subgroups. However, 2010-2014 and 2015-2022 had high heterogeneity, while 2000-2004 and 2005-2009 had low to moderate heterogeneity. At 36 months, OH was moderate, but there was a significant difference in the heterogeneity of Qmax outcomes between 5-year subgroups, with 2015-2022 having moderate heterogeneity, and 2000-2004 and 2010-2014 having moderate to high heterogeneity, while 2005-2009 had low heterogeneity.

Regarding PVR, the study found that at 3 months, there was no significant difference in the heterogeneity. However, at 12 and 36 months, there was a significant difference in the heterogeneity of PVR outcomes between continents. Europe had high heterogeneity in all three time periods. Africa had low heterogeneity in all three time periods. Asia had low heterogeneity at 3 months and 12 months but higher heterogeneity at 36 months. "Others” had no heterogeneity at 3 months and low heterogeneity at 12 months and 36 months. Besides that, the study found that at 3 months, there was a significant difference in the heterogeneity of PVR outcomes between 5-year groups, but not at 12 months. At 36 months, there was a significant difference in heterogeneity between 5-year groups. In each period, certain 5-year subgroups had low heterogeneity (2000-2004, 2005-2009, and 2010-2014), while others had high heterogeneity (2015-2022). 

For incontinence, the study found no significant difference between continents (Qm=6.97, p=0.07) and 5-year subgroups (Qm=4.44, p=0.22), with high overall heterogeneity (OH) (I2=86%). Within continent subgroups, Europe had low heterogeneity (I2=23.9%) and Africa had no heterogeneity (0%), while Asia and "Others" had high heterogeneity (I2=82.1% and I2=86.4%, respectively). Within 5-year subgroups, 2000-2004 and 2015-2022 had high heterogeneity (I2=91.7% and I2=86.4%, respectively), 2005-2009 had no heterogeneity (0%), and 2010-2014 had moderate heterogeneity (I2=82.1%). Furthermore, irritative symptom rates following TURP varied significantly between continents (Qm=10.46, p=0.02), with high OH (I2=97%). Europe had high heterogeneity (I2=96%), Africa had low heterogeneity (0%), Asia had high heterogeneity (I2=97.9%), and “Others” had low heterogeneity (I2=0%). There is significant heterogeneity between irritative symptom rates following TURP in different 5-year subgroups (Qm=16.48, p=0.00), with high OH (I2=86%). 2000-2004 had low heterogeneity (I2=0%), 2005-2009 had low heterogeneity (26.2%), 2010-2014 had high heterogeneity (I2=66.3%), and 2015-22 had high heterogeneity (I2=92.2%). Moreover, the study found no significant heterogeneity between Urinary Retention following TURP in different continents or 5-year subgroups. Moderate OH was observed in both continents and 5-year subgroups. Within the subgroups, Europe and 2000-2004 had moderate heterogeneity, while Asia and "Others" had low heterogeneity.

The current study findings revealed that Europe stands out as the most heterogeneous continent, possibly because of having the highest number of studies. While self-reported outcome measures were relatively similar across all continents, objective metrics varied significantly. Certain metrics demonstrated significant differences between Asia and Europe. Regarding TURP, IPSS reduction was relatively uniform, although Qmax and PVR varied depending on the continent and the year of the study. When examining the time distribution of the data, no clear trend was evident, suggesting that other factors beyond the continent and period could be contributing to the observed variability in outcomes. Notably, some continents and subgroups demonstrated higher levels of heterogeneity within their own groups, indicating that additional factors may produce variations in outcomes within these populations.

This study demonstrated that in the last 20 years there was not a clear trend in results of TURP, despite the development of new techniques. We highlighted that self-reported outcome measures were relatively consistent across continents, while objective metrics varied significantly, with PVR and Qmax showing more significant variation. The heterogeneity within continents may indicate a lack of standardization in TURP, however, the symptom improvement among patients is relatively uniform, what may explain why TURP is the best available option for BPH, even with variation in the way it is performed across different regions.