Use of the Prostate Health Index for detection of prostate cancer: results from a large academic practice

Abstract

BACKGROUNDThe Prostate Health Index (phi) outperforms PSA and other PSA derivatives for the diagnosis of prostate cancer (PCa). The impact of phi testing in the real-world clinical setting has not been previously assessed.METHODSIn a single, large, academic center, phi was tested in 345 patients presenting for diagnostic evaluation for PCa. Findings on prostate biopsy (including Grade Group [GG], defined as GG1: Gleason score [GS] 6, GG2: GS 3+4=7, GG3: GS 4+3=7, GG4: GS 8, and GG5: GS 9-10), magnetic resonance imaging (MRI), and radical prostatectomy (RP) were prospectively recorded. Biopsy rates and outcomes were compared to a contemporary cohort that did not undergo phi testing (n=1318).RESULTSOverall, 39% of men with phi testing underwent prostate biopsy. No men with phi<19.6 were diagnosed with PCa, and only 3 men with phi<27 had cancer of GG≥2. Phi was superior to PSA for the prediction of any PCa (AUC 0.72 vs. 0.47) and GG≥2 PCa (AUC 0.77 vs. 0.53) on prostate biopsy. Among men undergoing MRI and phi, no men with phi<27 and PI-RADS≤3 had GG≥2 cancer. For those men proceeding to RP, increasing phi was associated with higher pathologic GG (p=0.002) and stage (p=0.001). Compared to patients who did not undergo phi testing, the use of phi was associated with a 9% reduction in the rate of prostate biopsy (39% vs. 48%; p<0.001). Importantly, the reduction in biopsy among the phi population was secondary to decreased incidence of negative (8%) and GG1 (1%) biopsies, while the proportion of biopsies detecting GG≥2 cancers remained unchanged.CONCLUSIONSIn this large, real-time clinical experience, phi outperformed PSA alone, was associated with high-grade PCa, and provided complementary information to MRI. Incorporation of phi into clinical practice reduced the rate of unnecessary biopsies without changing the frequency of detection of higher grade cancers.

Whom to Biopsy

“…17–21 It is also associated with prostate cancer aggressiveness. In 658 men with PSA levels between 4 and 10 ng/mL, phi was compared with its individual variables for the prediction of clinically significant cancer.…”

“…Other studies have evaluated phi in conjunction with multiparametric MRI (mpMRI), with one finding a negative predictive value of 97% for clinically significant PCa in men undergoing repeat biopsy. 21,27 This suggests that phi remains useful in an MRI-based detection paradigm.…”

Prostate Health Index (PHI) improves prostate cancer detection at initial biopsy in Taiwanese men with PSA 4–10 ng/mL

“…Tosoian et al. prospectively assessed the combination of the PHI and MRI in 345 men undergoing radical prostatectomy, and found that none of the men with a PHI <27 and PI‐RADS (prostate imaging reporting and data system) score3 had Gleason group2 PCa [30]. Further studies are needed to refine the diagnostic accuracy of PHI.…”

Prostate cancer: unmet clinical needs and RAD9 as a candidate biomarker for patient management

“…Total PSA, if quantified on other analyzers, cannot be combined with the remaining analytes, so clinical labs would need to offer this test panel in addition to any other PSA testing they've already performed. The phi test outperforms PSA alone (7) and has 90% clinical sensitivity and 31% specificity at a phi value of 27.0 (www.beckmancoulter.com), allowing for a reduction of nearly 1/3 of all biopsies while detecting 90% of cancers.…”