Predicting surgical efficacy and diagnosing histological inflammation: the clinical significance of prostate exosome proteins in benign prostatic hyperplasia.

Background: Benign prostatic hyperplasia (BPH) is one of the most common causes of lower urinary tract symptoms (LUTS) among the aging male population. Recent studies have shown that histological inflammation (HI) plays a significant role in BPH, with prostatic exosomal protein (PSEP) identified as a potential biomarker for prostate diseases. Therefore, this study aimed to explore the effect of HI on LUTS in patients with BPH, and to further explore the clinical value of PSEP as a diagnostic biomarker of BPH complicated with HI and whether PSEP could be used as an index to predict the improvement of LUTS after operation. Methods: This study was an open-label, cohort study. The study enrolled all patients who were clinical diagnosed as BPH with LUTS and prepared to receive operation of the prostate at the Department of Urology of the Second Hospital of Hebei Medical University. International Prostate Symptom Score (IPSS) were used to evaluate the LUTS of the BPH. And the enrolled patients were divided into four groups, including none, mild HI, moderate HI, and severe HI, based on postoperative pathological results. Then the relationships between HI and IPSS, the National Institutes of Health-Chronic Prostatitis Symptom Index (NIH-CPSI), as well as PSEP were analyzed. Simple and multiple linear regression analyses were performed on the preoperative IPSS and the difference of IPSS before and after surgery was examined. SPSS software version 26 was used for statistical analysis and Prism 9.0 was used to make violin plots. Results: A total of 69 patients were enrolled in the study. The violin plot results indicated IPSS and NIH-CPSI scores exhibited significant increases in correlation with the severity levels of HI (P<0.001; P<0.001). Among BPH patients with total prostate-specific antigen (t-PSA) levels higher than 4.0 ng/mL, a significant correlation was observed between PSEP levels and HI (P=0.04). Besides, simple and multiple linear regression analysis showed that HI (P<0.001) or PSEP (P=0.03) was significantly associated with IPSS and improvement of LUTS, assessed by postoperative and preoperative IPSS differences. Conclusions: The study indicated that IPSS and PSEP (when t-PSA >4 ng/mL) were correlated with the severity of HI in patients with BPH. PSEP was linearly correlated with IPSS and the degree of reduction in IPSS after surgery. Consequently, PSEP may serve as a promising predictor for assessing surgical efficacy and diagnosing the severity of HI in patients with BPH.