Initial Prostate Health Index (phi) and phi density predicts future risk of clinically significant prostate cancer in men with initial negative prostate biopsy: a 6-year follow-up study

Background Men with elevated prostate-specific antigen (PSA) and initial negative prostate biopsy may have risk of prostate cancer (PCa) in the future. The role of Prostate Health Index ( phi ) in determining future PCa risk has not been studied before. This study aims to investigate the role of initial phi and phi density in predicting future PCa risk in men with initial negative biopsy. Methods Five hundred sixty nine men with PSA 4–10 ng/mL were recruited between 2008 and 2015 for prostate biopsy with prior phi . Electronic clinical record of men with initial negative biopsy was reviewed. Patients and follow-up doctors were blinded to phi . Kaplan–Meier curves were used to analyze the PCa-free survival in different baseline phi and phi density groups. Results Four hundred sixty-one men with complete follow-up data were included. Median follow-up is 77 months. PCa and HGPCa was diagnosed in 8.2% (38/461) and 4.8% (22/461) of cohort respectively. A higher baseline phi value was associated with PCa ( p = 0.003) and HGPCa ( p