Prostate-Specific Antigen Levels and Density in the Internal and External Glands of the Prostate in Benign Prostatic Hyperplasia Patients with Normal or Gray-Zone PSA Levels

Abstract

Objective: In patients with benign prostatic hyperplasia (BPH) showing normal prostate-specific antigen (PSA) levels (normal PSA group) and those with BPH showing gray-zone PSA levels (gray-zone PSA group), we assessed PSA levels secreted from the internal and external glands. Materials and Methods: We performed transurethral enucleation of the prostate (TUE) in 102 BPH patients with normal PSA and 59 BPH patients with gray-zone PSA at our department from 1999 to 2001. Preoperatively and approximately 6 months postoperatively, we measured serum PSA levels and determined prostatic volumes via transrectal ultrasonography (TRUS) to calculate PSA levels secreted from the internal and external glands as well as various PSA density (PSAD) values. Results: The total PSA level was 1.8 and 6.1 ng/ml in the normal and gray-zone PSA groups, respectively. The PSA level of the external gland was 0.6 and 0.8 ng/ml and the PSAD of the external gland was 0.07 and 0.08 ng/ml/cm³ in the normal and gray-zone PSA groups, respectively. The internal gland PSA was 1.3 and 5.4 ng/ml and the internal gland PSAD value was 0.11 and 0.30 ng/ml/cm³ in the normal and gray-zone PSA groups, respectively. Conclusions: Our results demonstrated that increased PSA levels in BPH cases with gray-zone PSA were attributable to increased PSA secreted from the internal gland rather than from the external gland. In our opinion, the determination of PSA and PSAD of the internal and external gland may be clinically significant in the future.