Application Of Prostate Health Index In The Early Clinical Detection Of Prostate Cancer

Background:Prostate cancer(PCa)is the most frequently diagnosed malignancy in male worldwide.Due to the long disease cycle and hiding symptoms,many patients have developed into the middle and advanced stages and have lost the opportunity of early treatment while they are diagnosed with prostate cancer.For a long period,Prostate specific antigen was widely used in early prostate cancer detection.However,as an organ-specific marker,PSA didn’t perform a satisfactory high specificity with the diagnostic threshold of 4.0 ng/mL.So people began to develop much more sensitive and specific tumor markers.Prostate health index(PHI)is a comprehensive indicator combining with total PSA,free PSA and p2PSA.And it has been approved by the US Food and Drug Administration(FDA)for use in the 4.0-10 ng/mL PSA range to reduce unnecessary prostate biopsies.However,the incidence of prostate cancer varies widely between different countries and ethnicities.In this current study,we investigated the diagnostic performances of PHI in a cohort of Chinese men with PSA<4 ng/mL,PSA 4-10 ng/mL,PSA 10-20 ng/mL and PSA>20ng/mL.Objective:We investigated the value of Prostate Health Index(PHI)in the diagnosis of prostate cancer with PSA<4 ng/mL,PSA 4-10 ng/mL,PSA 10-20 ng/mL and PSA>20ng/mL.Methods:210 patients treated in Nanjing First Hospital,Nanjing Medical University,from January 2013 to May 2016,who agreed for transrectal ultra-sound(TRUS)-guided 12-core prostate biopsy were recruited.Blood samples were taken immediately before TRUS-guided prostate biopsy.The performances of total PSA(tPSA),free-to-total PSA(f/tPSA),p2PSA,%p2PSA,and PHI were compared using receiver operating characteristic(ROC)with MedCalc 15.Results:From 2013 to 2016,210 patients were included.Among them,53 out of 210(25.2%)men were diagnosed to have prostate cancer on biopsy.In the group of PSA 4-10 ng/mL,the difference of%p2PSA、PHI between PCa and non-PCA groups is statistically significant(p=0.000,0.000).The area under the curve(AUC)of PHI is significantly greater than the area under the curve of tPSA,fPSAand p2PSA(p<0.05).There is no statistically significant difference between the AUC of PHI,f/tPSA and%p2PSA.In the group of PSA 10-20 ng/mL,the difference of%p2PSA、PHI between PCa and non-PCA groups is statistically significant(p=0.021,0.003).The area under the curve(AUC)of PSA,fPSA,f/tPSA,p2PSA,%p2PSA and PHI is 0.520,0.533,0.524,0.682,0.780 and 0.788 respectively.The area under the curve(AUC)of PHI is significantly greater than the area under the curve of tPSA,fPSA,f/tPSA,p2PSA and%p2PSA(p<0.05).In the group of PSA>20 ng/mL,there is no statistically significant difference between the AUC of PHI and tPSA、fPSA、p2PSA、%p2PSA.But the difference of PHI and f/tPSA between PCa and non-PCA groups is statistically significant(p<0.05).The proportions of men with positive biopsies were 4.4%in PHI<35,22.8%in PHI 35-60,and 58.0%in PHI>60(chi-square test,p<0.05).Furthermore,PHI was positively correlated with the Gleason score(p<0.05).Conclusions:PHI performed well in predicting prostate cancer and high grade prostate cancer. While PSA is between 4 and 10 ng/mL,PHI has similar abilities with f/tPSA、%p2PSA in early prostate cancer prediction,but it is much better than single PSA、fPSA、p2PSA.While PSA is higher than 10 ng/mL,PHI performed much better than tPSA,fPSA,f/tPSA,p2PSA and%p2PSA in predicting prostate cancer.It can be used to predict patients with PCa Gleason score which is of some significance for evaluating the prognosis of patients with PCa.The best diagnostic value of PHI is 42.16.If we set 35 as the diagnostic value,68/210(32.4%)of unnecessary prostate biopsy can be avoided.