PSA change after antibiotic treatment should not affect decisionmaking on performing a prostate biopsy.

Background: To investigate the effect of antibiotic treatment on PSA when deciding on prostate biopsy.

Methods: A total of 206 patients with an elevated PSA level (2.5-30) were included. Mp-MRI could be done on 129 patients. Patients were given ciprofloxacin (500 mg, b.i.d. p.o.) for 4 weeks and PSA measurements were repeated. Systematic prostate biopsy was performed regardless of PSA changes on all patients. Additionally, cognitive biopsies were performed from PI-RADs III, IV, and V lesions.

Results: : Prostate cancer was detected in 36.4% of patients. 53.3% had Gleason score of 3+3, 46.7% had Gleason score ≥ 3+4. PSA values decreased in 56.3% and in 43.7% and remained the same or increased but cancer detection rates were not different: 34.5% vs. 38.9%, respectively (p = 0.514). PSA change in whole group was significant (6.38 ng/mL vs. 5.95 ng/mL, respectively (p = 0.01). No significant PSA decrease was observed in cancer patients (7.1 ng/mL vs. 7.05 ng/mL, p = 0.09), whereas PSA decrease was significant in patients with benign pathology (6.1 ng/mL vs. 5.5 ng/mL, p = 0.01). In patients with PI-RADs IV-V lesions, adenocarcinoma was present in 33.9% and 30.4% with or without PSA decrease, respectively (p = 0.209). Clinically significant cancer was higher in patients with after antibiotherapy PSA values >4 ng/mL regardless of PI-RADs grouping (p = 0.08). Addition of any PSA value to PI-RADs grouping did not have any significant effect on the detection of cancer.

Discussion: PSA change after antibiotic treatment has no effect in detecting cancer and should not delay performing a biopsy.