Imaging

Abstract

Similarly since 2005, we have been using the multiparametric evaluation for the detection of prostate cancer in patients with elevated PSA and negative prostate biopsies. Multiparametric evaluation is a combination of conventional endorectal T2-weighted image, spectroscopy, diffusion-weighted image and perfusion study (dynamic contrast-enhanced MRI). Using only MRI and MRSI results to target an endorectal sonographically guided biopsy in men with highly suspicious spectral trace for prostate cancer the sensitivity, specificity, positive and negative predictive values, and accuracy were 71%, 84%, 75%, 81%, and 79%, respectively (2). In this group of patients with at least two negative biopsies the finding of more than one focal area with low-signal intensity on T2-weighted image, suspicious for cancer, is not infrequent. These focal areas with reduced T2 signal intensity in peripheral zone are probably related to post-biopsies scarring. In our experience these abnormalities may be disregarded as a suspicious lesions based on spectroscopic imaging alone or combined with diffusion-weighted image and perfusion study. Based on this complete MRI work-up an similarly to cancer of transition zone (3), we feel that the best results for the detection of cancer of the peripheral zone in patients with negative biopsies, will be accomplished by the combination of the results of these 4 techniques (a retrospective analysis of this materials and methods has already been initiated). It is interesting to emphasize that these techniques are complimentary since they are based in different biologic principles. In view of the results of this well designed multicenter trial, perhaps in the near future, it will be interesting to confirm if multiparametric MRI evaluation is of incremental value for the detection of prostate cancer in the larger group of patients without previous biopsy. Dr. Adilson PrandoChief, Department of Radiology and Diagnostic Imaging, Vera Cruz Hospital Campinas, São Paulo, Brazil E-mail: adilson.prando@gmail.com Urinary bladder cancer: diffusion-weighted MR imaging--accuracy for diagnosing T stage and estimating histologic gradeTakeuchi M, Sasaki S, Ito M, Okada S, Takahashi S, Kawai T, Suzuki K, Oshima H, Hara M, Shibamoto Y Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan Radiology. 2009; 251: 112-21 Purpose: To prospectively evaluate the ability of diffusion-weighted (DW) magnetic resonance (MR) imaging to be used to determine the T stage of bladder cancer and to measure the correlation between the apparent diffusion coefficient (ADC) and histologic grade. Materials and Methods: This study was approved by the local institutional review board. All patients gave written informed consent. Forty patients with a total of 52 bladder tumors underwent MR imaging that included