Prostate cancer detection rate and the importance of premalignant lesion in rebiopsy

Establish the prostate cancer (PCa) detection rate and the premalignant lesion incidence, as well as their importance in cancer detection at the first rebiopsy.

In the period 2006-2008, at the CCUS Urology Clinic, there were 585 prostate biopsies performed in 515 patients. 12% of the patients underwent the first biopsy due to premalignant lesion findings. The main characteristics of the patients--age, prostate specific antigen (PSAt)-total and PSA ratio (PSAr), the number of needle biopsies, Gleason score and the role of premalignant lesions in diagnosis of PCa at the first rebiopsy were processed retrospectively.

Primarily detected PCa amounted to 32.4% (167/515), while the rebiopsy showed the detection rate of 35.7% (25/70). No statistically significant age or PSAt and PSAr difference was observed, while there was, however, a difference in the number of biopsy samples, 11 (6-18) vs. 12 (8-20) and in the Gleason score (6.5 vs. 5.9) among the observed groups (p < 0.05). Atypical small acinar proliferation (ASAP) and high grade intra epithelial neoplasia (HGPIN), were found in 4.95% and 7.2% of the cases, while the ASAP + HGPIN combination was found in 1.5% of the cases. The PCa detection rate at the first rebiopsy in patients with ASAP, HGPIN and ASAP + HGPIN lesions was 50%, 23.6% and 50%, respectively. The ANOVA test showed a statistically significant shorter time period for rebiopsy in ASAP+HGPIN patients than that of patients with ASAP and HGPIN lesions.

A repeated positive biopsy establishes PCa in patients with lower PSAt values and the Gleason score, which is followed by an increased number of biopsy samples. ASAP and ASAP + HGPIN lesions carry a higher specificity of75% and 91%, respectively, while the PPV in prostate cancer detection for HGPIN is low (24%).