Pilot study on predictive value of plasmatic levels of 9 angiogenetic biomarkers in selection of patients candidate to prostate biopsy

To reduce the number of negative prostate biopsies in patients with elevated PSA serum levels represents a major challenge in urological oncology. Angiogenetic factors might be involved in initial stages of prostate cancer and might represent useful tools in patients’ selection for prostate biopsy.

The plasmatic levels of Angiopoietin-2, Follistatin, G-CSF, HGF, IL-8, Leptin, PDGF-BB, PECAM-1 and VEGF were measured by BioPlex immunoassay in patients undergoing prostate biopsy for palpable prostate nodule and/or elevated PSA levels (≥4 ng/mL). They were related with biopsy results. ROC curve analysis was exploited to test the diagnostic accuracy of each biomarker by AUC calculation. A potential cut-off level was computed.

Fifty patients were entered. Median PSA was 6.8 ng/mL. A prostate nodule was palpable in 18 (36%) patients. The median number of biopsy cores was 12. Prostate cancer was detected in 25 (50%) and ASAP and PIN in 2 more patients (4%) respectively. Among the 9 considered biomarkers, only leptin showed an interesting diagnostic performance with an AUC of 0.781, at a cut-off value of 2.11 ng/mL, demonstrating a sensitivity of 78%, a specificity of 77% and a positive predictive value of 85%. Main limitations of our study are the exploratory design and the criteria adopted for patients’ selection determining a detection rate for prostate cancer above the usual range.

Leptin only, in our preliminary study, shows promising diagnostic accuracy for the selection of patients candidate to prostate biopsy. Further studies are required to confirm its diagnostic value and its relation with BMI.