Study of Prostatic Fluid from Patients with Elevated Levels of Prostate-Specific Antigen

Introduction: Characteristics of prostatic fluid (PF), which can be obtained in large amounts during screening transrectal ultrasound just before prostate biopsy to detect prostate cancer, were investigated. These characteristics include the amount of PF obtained and the number of leukocytes in PF, which would be useful for planning cell-biological or immunological studies of leukocytes in PF and for increasing the understanding of prostatitis in elderly men. Patients and Methods: The volume of PF and the number of leukocytes in PF were measured in 50 patients suspected of having prostate cancer because of elevated levels of serum prostate-specific antigen (PSA). Correlations of the volume of PF, the number of leukocytes per milliliter, the total leukocyte number with age and prostate volume and correlation of PSA levels with the number of leukocytes per milliliter and total leukocyte number were also investigated. Results: The average patient age was 67.2 years, and PF specimens were obtained from 43 of the 50 patients (86%). The mean ± SD of PF volume, number of leukocytes in PF, and total leukocyte number were 347.65 ± 305.76 μl, 4.84 ± 6.07 × 106 /ml, and 1.47 ± 2.10 × 106, respectively. A correlation was observed only between the total leukocyte number and the volume of the transitional zone (P=0.039). Conclusions: These data provide information for investigators to plan cell-biological or immunological studies of leukocytes in PF and for understanding prostatitis in elderly men.