Infectious Complications of Conventional Laparoscopic vs Robotic Laparoscopic Prostatectomy: A Systematic Literature Review and Meta-Analysis

BACKGROUND

Recent studies have shown that using minimally invasive surgical techniques (conventional laparoscopy or robotic) for prostatectomy is associated with lower perioperative complication rates compared with open radical retropubic prostatectomy. However, differences in infectious complications between these minimally invasive approaches are not well characterized. To study this further, we performed a systematic review of the literature and meta-analysis of the infectious complications of prostatectomy, comparing robotic prostatectomy (RP) with conventional laparoscopic prostatectomy (LP).

METHODS

We searched PubMed, CINAHL, CDSR, and EMBASE through September 2018 for studies evaluating minimally invasive prostatectomy and infectious complications. We employed random-effect models to obtain pooled odds ratio (pOR) estimates. Heterogeneity was evaluated with I² estimation and the Cochran Q statistic. pORs were calculated separately based on the indication for prostatectomy.

RESULTS

Fifteen studies were included in the final review for the meta-analysis with 14,121 patients undergoing minimally invasive prostatectomy. There was no statistically significant difference in the number of infectious complication events between RP and LP (pOR 0.94; 95% CI 0.50, 1.76). When we performed a stratified analysis, similar results were found with no statistically significant difference in infectious complications comparing RP with LP among patients with prostate cancer (pOR 0.73; 95% CI 0.43, 1.24). We observed that infectious complications were nearly threefold higher with the robotic approach in earlier studies (published between 2007 and 2012, pOR 2.81; 95% CI 1.07, 7.39), but no significant difference was found in later studies (between 2013 and 2018, pOR 0.80, 95% CI 0.40, 1.57).

CONCLUSIONS

The rate of infectious complications associated with RP was no different than that associated with conventional LP.

SRD5A2 gene polymorphisms and the risk of benign prostatic hyperplasia but not prostate cancer

BACKGROUND

Testosterone, a primary androgen in males, is converted into its most active form, dihydrotestosterone (DHT), by 5α-reductase type 2 (encoded by the SRD5A2 gene) in the prostate. DHT is necessary for prostatic growth and has five times higher binding affinity than testosterone for androgen receptors. We hypothesized that polymorphic variations in the SRD5A2 gene may affect the risk of benign prostatic hyperplasia and prostate cancer.

MATERIALS AND METHODS

We analyzed SRD5A2 gene polymorphisms in 217 BPH patients, 192 PCa cases, and 171 controls. Genotyping was undertaken using direct DNA sequencing. Genotype data were compared between cases and controls using a Chi square statistical tool.

RESULTS

We found that the A49T locus was monomorphic with 'AA' genotype in all subjects. At V89L locus, the presence of 'VV' showed a marginally significant correlation with increased BPH risk (p=0.047). At the (TA)n locus, longer TA repeats were found to be protective against BPH (p=0.003). However, neither of these polymoprhisms correlated with the risk of PCa.

CONCLUSIONS

We conclude that A49T is monomorphic in the study population, VV marginally correlates with BPH risk, and longer (TA)n repeats are protective against BPH. None of these polymorphisms affect the risk of PCa.

TCTP is an androgen-regulated gene implicated in prostate cancer

TCTP has been implicated in a plethora of important cellular processes related to cell growth, cell cycle progression, malignant transformation and inhibition of apoptosis. In addition to these intracellular functions, TCTP has extracellular functions and plays an important role in immune cells. TCTP expression was previously shown to be deregulated in prostate cancer, but its function in prostate cancer cells is largely unknown. Here we show that TCTP expression is regulated by androgens in LNCaP prostate cancer cells in vitro as well as human prostate cancer xenografts in vivo. Knockdown of TCTP reduced colony formation and increased apoptosis in LNCaP cells, implicating it as an important factor for prostate cancer cell growth. Global gene expression profiling in TCTP knockdown LNCaP cells showed that several interferon regulated genes are regulated by TCTP, suggesting that it may have a role in regulating immune function in prostate cancer. In addition, recombinant TCTP treatment increased colony formation in LNCaP cells suggesting that secreted TCTP may function as a proliferative factor in prostate cancer. These results suggest that TCTP may have a role in prostate cancer development.

Null genotypes at the GSTM1 and GSTT1 genes and the risk of benign prostatic hyperplasia: a case-control study and a meta-analysis

BACKGROUND

Benign prostatic hyperplasia (BPH) is an age related non-malignant disease diagnosed as lower urinary tract symptoms and prostatic enlargement. Null genotypes in drug detoxification glutathione-S-transferase genes/enzymes, such as GSTT1 and GSTM1 have been reported to increase risk of several cancers including prostate. Meta-analysis on PC also suggested significant impact of GSTM1 null genotype but not that of GSTT1; however, BPH data have not been subjected to meta-analysis.

METHODS

We investigated GSTT1 and GSTM1 genotypes in 429 subjects which included 244 BPH, 51 prostate cancer (PC) patients, and 134 control subjects to find if null genotype in any of the two genes increased the risk of BPH/PC. We also performed a quantitative meta-analysis on 888 BPH cases and 793 controls for GSTM1 and on 890 BPH cases and 793 controls for GSTT1 to assess overall consensus about the impact of null genotypes on BPH risk.

RESULTS

We did not find any significant difference in the distribution of genotypes of either of the two genes between BPH/PC cases and controls; however, double deletion (GSTM1 null + GSTT1 null) increased BPH risk, significantly. Upon meta-analysis, null genotype of GSTM1 but not that of GSTT1 appeared to strongly affect BPH risk.

CONCLUSIONS

In our population, null genotypes of either GSTM1 or GSTT1 do not appear to affect BPH risk; however, the double deletion was significantly associated with BPH. Meta-analysis suggested significant influence of GSTM1 null genotype but not that of GSTT1 on BPH risk.