Increased rate of positive biopsies using a combination of MR-tomography, spectroscopy and diffusion-weighted magnetic resonance imaging prior to prostate biopsies in patients with persistent elevated prostate-specific antigen values: a retrospective analysis

ABSTRACT

Persistently elevated prostate-specific antigen [PSA] values following negative biopsies result in a diagnostic dilemma. In order to improve detection rates in patients with former negative biopsies and persistently elevated PSA values, magnetic resonance tomography [MRT], magnetic resonance spectroscopy [MRS], and diffusion-weighted magnetic resonance imaging [DW-MRI] were performed prior to prostate rebiopsies. Over a 14-month period, 67 patients [mean age of 66 years] with a history of 1-5 negative biopsies underwent endorectal magnetic resonance imaging [MRI] using T2-weighted MRT MRS and DW-MRI before an additional prostate biopsy was performed. Subsequently, 5 contrast-enhanced transrectal ultrasound-guided biopsies were performed according to a 10-core systematic scheme. Out of the 67 men, 25 patients had positive biopsies and opted for radical prostatectomy. Histological evaluation of cancer localization, PSA, diameters of primary tumors, numbers and diameters of satellite tumors, prostate volume, and staging pathology was performed. These findings were compared with MRI and MRS results. Serum PSA levels ranged from 3.1 to 19.5 g/ml [median level of 7.96 ng/ml]. After the 25 patients underwent radical prostatectomy, analysis of 20 whole-mount sections of 25 radical retropubic prostatectomy [RPE] specimens presented results agreeing with the tumor location from MRI and MRS data. The aim of image-guided diagnostics should be to provide more critical information prior to biopsy. Furthermore, the acquisition of such data is important for better risk stratification in therapeutic decisions