[Relationship of prostate volume and inflammatory cell infiltration with the positive rate of prostate biopsy]

Objective: To investigate the factors influencing the positive rate of prostate biopsy and its relationship with the prostate volume and inflammatory cell infiltration (ICI).

Methods: We retrospectively analyzed the clinical data on 230 cases of double-plane transrectal ultrasound-guided prostate biopsy in our Department of Urology, including the patients' age, body mass index (BMI), serum total prostate-specific antigen (tPSA), PSA density (PSAD), prostate volume, and ICI in the prostate tissue. We also investigated the relationship of the above factors with the pathological results of prostate biopsy by binary logistic regression analysis.

Results: The positive rate of prostate biopsy was 38.7% (89/230) in the total number of cases, 28.57% (n = 56) in the 196 cases with tPSA < 100 μg/L, and 97.06% (n = 33) in the 34 cases with tPSA ≥ 100 μg/L. Binary logistic regression analysis showed that the positive rate of prostate biopsy in those with tPSA < 100 μg/L was correlated positively with age (P < 0.01, OR = 1.09), tPSA (P < 0.01, OR = 1.04) and PSAD (P < 0.01, OR = 10.04), negatively with the prostate volume (P < 0.01, OR = 0.98) and ICI (P < 0.01, OR = 0.22), but not with BMI (P > 0.05). As a predictor of positive prostate biopsy, tPSA > 10 μg/L exhibited a sensitivity of 82.14% and a specificity of 35.71%, while PSAD > 0.26 showed a sensitivity of 78.57% and a specificity of 71.43%.

Conclusions: Non-specific elevation of the tPSA level induced by increased prostate volume and inflammatory cell infiltration may lead to unnecessary biopsies in some patients. As a predictor of positive prostate biopsy, PSAD > 0.26 has a higher clinical application value than tPSA > 10 μg/L.