Authors (including presenting author) :
Chiu KFP(1), Lau BS(2), Li SY(1), Ho CC(3), Kwok SW(1), Teoh JY(2), Yee CH(1), Chan CK(1), Hou SM(1), Tang WL(3) , Ng CF(2), Poon WT(3)
Affiliation :
(1)Division of Urology, Department of Surgery, Prince of Wales Hospital, (2)SH Ho Urology Centre, The Chinese University of Hong Kong, (3)Department of Pathology, Pamela Youde Nethersole Eastern Hospital
Introduction :
The blood test Prostate Specific Antigen (PSA) has been used for prostate cancer detection for many years, but it has poor accuracy in predicting cancer. This created a lot of dilemma for Urologists and a lot of unnecessary prostate biopsies were performed. Prostate Health Index (PHI) is a new blood test that can stratify risks of prostate cancer in men with elevated PSA of 4-10 ng/mL. Since May 2016, Urologists in all HA hospitals can order the PHI test for eligible patients. All PHI blood tests were performed in the laboratory in PYNEH.
Objectives :
To prospectively evaluate the impact of introducing PHI test in reducing unnecessary prostate biopsies in HA setting.
Methodology :
All men with elevated PSA and normal digital rectal examination (DRE) with PHI test taken in all HA hospitals between May 2016 and August 2017 were included. Rate of biopsy and biopsy outcome including 2 year follow up were related to initial PHI measurements.
Result & Outcome :
2,839 consecutive men with a median PSA of 6.1 (IQR 4.6-8.1)ng/mL were included. In men with PSA < 10ng/mL, 82.0% (n=2528) decided NOT to have a biopsy after knowing their PHI result. 81.4% of these men had PHI < 35 (low risk range) and 88.5% men in this group opted for PSA follow-up instead of biopsy, while 46.4% with PHI >35 opted for biopsy. By selecting higher risk men for biopsy with PHI, the positive biopsy rate improved from historical data of 10.7% to 28.3%, and half of them had high grade (Gleason grade group ≥2) cancers. In the first 1392 non-cancerous men with a median of 2.2 (range 2.0-2.6) years of follow-up, 9.8% (110/1127) in PHI< 35 and 26.4% (70/265) in PHI>35 had a biopsy within available follow-up (p< 0.001), resulting in diagnoses of 11.0% (12/109) and 28.6% (20/70) high grade cancer respectively (p=0.003). In conclusion, by incorporating PHI into the routine clinical pathway, 80% of unnecessary biopsies were avoided. This in turn reduced hospital costs and patient morbidity related to these biopsies. High grade prostate cancer detection rate improved as compared to historical data when biopsy decisions were only based on a PSA test. A higher baseline PHI was correlated to subsequent biopsy outcome and as such can serve as a tool to reduce the frequency of follow-up visits in low risk patients.
