Incidence of insignificant prostate cancer using free/total PSA: results of a case-finding protocol on 14,453 patients.

To evaluate prostate cancer (PCa) detection and incidence of pathologically insignificant PCa (pIPCa) tumour using percent-free PSA (%f-PSA) in patients with total PSA ≤ 10 ng ml(-1). From February 2002 to October 2009, 14,453 patients (median 60.5 years) were enrolled in a case-finding protocol for the early diagnosis of PCa. Indications to biopsy were suspicious digital rectal examination; PSA >10 ng ml(-1); PSA ≤ 2.5 ng ml(-1), included between 2.6-4 and 4.1-10 ng ml(-1) with %f-PSA <15, <20 and <25%, respectively. A median of 18 and 26 cores in case of primary and repeated biopsy were determined; 2123 men underwent prostate biopsy, of whom 1589 (74.8%) had a PSA ≤ 10 ng ml(-1). A PCa was found in 777 (36.6%) and in 35 (23.3%) patients at primary and repeated biopsy: 459 and 26 men had PSA ≤ 10 ng ml(-1) and 419 and 26 patients underwent surgery, respectively, 244 (58.3%) and 18 (69.2%) had an organ-confined PCa with a pIPCa incidence equal to 1.4 and 7.7%, respectively. Cancer detection rate of 28.8% in patients with PSA ≤ 10 ng ml(-1) associated with a low incidence of pIPCa should induce to introduce %f-PSA in screening programmes to reduce the risk of overdiagnosis.