Antibiotherapy has shown a clinically significant decrease in PSA levels in some patients. However, the clinical benefit of this decrease, which would increase the diagnostic efficacy of PSA, has not yet been established. To our knowledge, PSA half-life and PSA-ENT2.5 (expected normalization time according to 2.5 ng/mL cut-off value) were unexamined parameters. The aim of this study is to investigate the efficacy of PSA-ENT2.5 and PSA half-life after antibiotherapy for predicting prostate cancer diagnosis.
64 patients with a PSA value in gray scale (2.5-10 ng/mL) were included in this prospective study. Two weeks of oral levofloxacin treatment was given to all of the patients. Twelve core prostate biopsies were performed after antibiotherapy in all cases. Patients were divided into two groups as biopsy-proven cancer patients and non-cancer biopsy groups, and were compared according to PSA-ENT2.5 and PSA half-life.
The mean PSA half-life (624.6 ± 1062 days) was higher in the group with prostate cancer than in the group without prostate cancer (390.2 ± 476) (p = 0.49). PSA-ENT2.5 was higher in prostate cancer detected group (p = 0.16). There was no statistically significant difference between the two groups for other dynamic parameters (PSA reduction rate and value change). However, the most statistical powerfull parameter was PSA-ENT2.5 in all dynamic PSA parameters.
Antibiotherapy provides a clinically significant reduction in patients with PSA level gray scale (2.5-10 ng/mL). PSA half life and PSA-ENT2.5 are promising new parameters that can be used for this purpose. A larger scale prospective study is needed in this area.