Risk Assessment Models To Evaluate The Necessity Of Prostate Biopsies For Patients With PSA 4-50 Ng/mL

Background:The prostate-specific antigen(PSA)has been widely used to screen for prostate cancer but its low specificity resulted in increasing false positive rates of prostate biopsies.Objective:To develop a new risk assessment model to overcome the diagnostic limitation of PSA and the lack of health screening awareness to reduce unnecessary prostate biopsies for patients with PSA 4-50 ng/mL.Methods:702 patients in seven hospitals with PSA 4-10 ng/mL or 10-50 ng/mL who had undergone transrectal ultrasound-guided prostate biopsies were analyzed during analysis-modeling stage for several clinicopathological indexes related to prostate cancer and renal function.Multiple logistic regression analyses were used to develop new risk assessment models of prostate cancer for both PSA levels ranges 4-10 and 10-50 ng/mL.In the external validation stage,the new models were applied to assess the necessity of biopsy.Results:In analysis-modeling stage,the new models of PSA 4-10 ng/mL group and PSA 10-50 ng/mL group performed significantly better than PSA alone for detection of cancers.Both the PSA groups' models showed higher area under the curve(0.937 and 0.873)than that for PSA(0.624 and 0.595),respectively at a pre-determined cut-off(0.1067 and 0.6183).Patients above these values were recommended to undergo biopsies immediately while the others continued close active observation.Compared with the analysis-modeling stage,the detection rate of prostate cancer in the external validation stage was significantly increased(39.29%vs 17.79%,p=0.006 and 71.83%vs 50.0%,p=0.015,respectively)for PSA ranges 4-10 and 10-50 ng/mL groups.Conclusions:We developed risk assessment models for patients with PSA 4-50 ng/mL to reduce unnecessary prostate biopsies and increase the detection rate of prostate cancer.