PI-RADS classification: prognostic value for prostate cancer grading

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1 PI-RADS classification: prognostic value for prostate cancer grading Poster No.: C-1622 Congress: ECR 2014 Type: Scientific Exhibit Authors: I. Platzek, A. Borkowetz, T. Paulus, T. Brauer, M. Wirth, M. Laniado; Dresden/DE Keywords: DOI: Genital / Reproductive system male, Oncology, MR, MR-Diffusion/ Perfusion, Diagnostic procedure, Neoplasia /ecr2014/C-1622 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 5

2 Aims and objectives The PI-RADS classification was introduced by the European Society of Urogenital Radiology (ESUR) in order to standardize reporting in magnetic resonance imaging (MRI) of the prostate. The aim of the current study was to determine the prognostic value of PI- RADS scores in regard to tumor grade (Gleason score) in patients with prostate cancer. Methods and materials The study was approved by the local ethics committe and written informed consent was waived. Nineteen patients who underwent radical prostatectomy and had a prior MR examination of the prostate were included in this retrospective study (age y, 67 y on average). Average PSA level was 11,5 ng/dl (range: 0,2 ng/dl - 49,5 ng/dl). The patients were examined on a 3T MR scanner and a pelvic phased-array coil was used for signal acquisition. The MR examination included T2-weighted images in axial, coronal and sagittal orientation, axial T1-weighted images without contrast enhancement, contrastenhanced dynamic axial T1-weighted gradient echo images and axial diffusion-weighted images. The images were independently evaluated by two board-certified radiologists (with seven years and three years experience in prostate MR, respectively). In cases with differing results, the PI-RADS score was assigned in consensus. Cohen`s kappa was used to assess interrater agreement. Gleason scores were based on histological evaluation of the prostatectomy specimen. Spearman`s rank correlation coefficient was used to assess the relationship between PI-RADS scores and Gleason scores. Results MR identified 19 prostate lesions, one in each patient. One lesion received a PI-RADS score of 2, two lesions had a score of 3, fourteen lesions received a score of 4, and two lesions received the highest score, 5. Interrater agrrement was good (# = 0,92). Histopathologic evaluation classified 12 tumors as T2c and 7 tumors as T3a. Thirteen patients had a Gleason score of 7, four had a score of 6 and two had a score of 9. One patient had a solitary iliacal lymph node metastasis, while the remaining 18 patients had no metastatic disease. Spearman`s rank correlation coefficient was 0,2 (p=0,41), indicating low correlation between PI-RADS and Gleason scores. Images for this section: Page 2 of 5

3 Fig. 1: Seventy-two-years-old man. Tumor in the left posterior peripheral zone (arrow), hypointense and circumscribed on T2-weighted images (A), with strong contrast uptake in the arterial phase of the dynamic T1-weighted scan (B) and restricted diffusion seen on the apparent diffusion coefficient (ADC) map (C). The lesion was rated as PI-RADS 4, while the histopathological evaluation resulted in a Gleason score of 7. Page 3 of 5

4 Fig. 2: Fifty-seven-years-old man. A slightly hypointense lesion is recognized in the right peripheral zone on T2-weighted images (A). The lesion is not recognizable on the ADC map (B). The perfusion map (C) and the corresponding contentration-time curve (D) show a mild washout. The lesion was rated as PI-RADS 3 and Gleason 7, respectively. Fig. 3: Sixty-six-years-old man. Tumor in the right anterior part of the transitional zone (arrow), hypointense and circumscribed on T2-weighted images (A), with strong contrast uptake in the arterial phase of the dynamic T1-weighted scan (B) and circumscribed restricted diffusion seen on the ADC map (C). As extracapsular growth was suspected, the lesion was rated as PI-RADS 5. The histopathological evaluation resulted in a Gleason score of 6. Page 4 of 5

5 Conclusion Our preliminary results indicate that PI-RADS scores have limited prognostic value in regard to tumor grade, as the correlation of PI-RADS score and Gleason scores is low. The role of PI-RADS as an independent predictor of prognosis has yet to be evaluated. Personal information References 1. Rothke, M., et al., [PI-RADS classification: structured reporting for MRI of the prostate]. Rofo, (3): p Barentsz, J.O., et al., ESUR prostate MR guidelines Eur Radiol, (4): p Sosna, J., et al., MR imaging of the prostate at 3 Tesla: comparison of an external phased-array coil to imaging with an endorectal coil at 1.5 Tesla. Acad Radiol, (8): p Weinreb, J.C., et al., Prostate cancer: sextant localization at MR imaging and MR spectroscopic imaging before prostatectomy--results of ACRIN prospective multiinstitutional clinicopathologic study. Radiology, (1): p Page 5 of 5