Objectives: To assess the diagnostic performance, predictors, and clinical utility of MRI-guided prostate biopsy over an 18 year period in a real-world tertiary care setting. Materials and methods: We retrospectively analyzed patients who underwent MRI-guided prostate biopsy between 2006 and 2024 at a German tertiary care center. Clinical data, PI-RADS, PSA levels, prostate volume, and biopsy outcomes were evaluated. Logistic regression models assessed associations between clinical variables and cancer detection, clinical significance (ISUP ≥ 3), and upgrading after radical prostatectomy (RPE). Results: Among 496 patients (mean age 66 ± 8 years; PSA, median (IQR): 7.2 ng/ml (5–10)), cancer was detected in 33% (162/496), with 29% (47/162) classified as clinically significant. In our biopsy cohort (PI-RADS 3: 12.7%, PI-RADS 4: 43.0%, PI-RADS 5: 5.6%), clinically significant prostate cancer (ISUP ≥ 3) was detected in 3.2% of PI-RADS 3, 12.2% of PI-RADS 4, and 28.6% of PI-RADS 5 lesions. PI-RADS 5 lesions were strongly associated with cancer detection (OR 3.6, 95% CI 1.35–10.13) and significant disease (OR 7.1, 95% CI 1.38–55.15), independent of age, prostate volume, and biopsy extent. While these covariates predicted overall biopsy positivity (p < 0.02), they were not associated with significant cancer (p > 0.05) or upgrading at RPE (p > 0.05). Among 29 RPE patients, only one was upgraded. Post-biopsy CT was performed in all patients: MRI-guided biopsy was associated with a low complication rate: minor localized bleeding occurred in 4.4% of cases, and no major adverse events were observed. Conclusions: MRI-guided prostate biopsy showed high diagnostic accuracy and safety in routine care. PI-RADS was the key predictor of clinically significant cancer. The low rate of upgrading after RPE supports its reliability in guiding patient management and avoiding overtreatment. Clinical relevance statement: MRI-guided prostate biopsy enables accurate detection of clinically significant prostate cancer with low risk of understaging, supporting its routine use in personalized urologic oncology.