Detection and staging of radio-recurrent prostate cancer using multiparametric MRI

Abstract

Objective: We determined the sensitivity and specificity of multiparametric magnetic resonance imaging (MP-MRI) in detection of locally recurrent prostate cancer and extra prostatic extension in the post-radical radiotherapy setting. Histopathological reference standard was whole-mount prostatectomy specimens. We also assessed for any added value of the dynamic contrast enhancement (DCE) sequence in detection and staging of local recurrence. Methods: This was a single centre retrospective study. Participants were selected from a database of males treated with salvage prostatectomy for locally recurrent prostate cancer following radiotherapy. All underwent pre-operative prostate-specific antigen assay, positron emission tomography CT, MP-MRI and transperineal template prostate mapping biopsy prior to salvage prostatectomy. MP-MRI performance was assessed using both Prostate Imaging-Reporting and Data System v. 2 and a modified scoring system for the post-treatment setting. Results: 24 patients were enrolled. Using Prostate Imaging-Reporting and Data System v. 2, sensitivity, specificity, positive predictive value and negative predictive value was 64%, 94%, 98% and 36%. MP-MRI under staged recurrent cancer in 63%. A modified scoring system in which DCE was used as a co-dominant sequence resulted in improved diagnostic sensitivity (61%–76%) following subgroup analysis. Conclusion: Our results show MP-MRI has moderate sensitivity (64%) and high specificity (94%) in detecting radio-recurrent intraprostatic disease, though disease tends to be under quantified and under staged. Greater emphasis on dynamic contrast images in overall scoring can improve diagnostic sensitivity. Advances in knowledge: MP-MRI tends to under quantify and under stage radio-recurrent prostate cancer. DCE has a potentially augmented role in detecting recurrent tumour compared with the de novo setting. This has relevance in the event of any future modified MP-MRI scoring system for the irradiated gland.

Magnetic resonance imaging (MRI) for local staging before salvage radical prostatectomy: a meta-analysis

“…Since biopsy provides limited and indirect insight into local pathological advancement these studies cannot be used for the validation of MRI as a staging tool. To the best of our knowledge, to date, only four studies have used whole-mount specimens as references for the evaluation of MRI staging performance [10][11][12][13] before salvage radical prostatectomy (SRP).…”

Importance of magnetic resonance imaging and prostate‐specific membrane antigen PET‐CT in patients treated with salvage radical prostatectomy for radiorecurrent prostate cancer

“…Up to now few studies, which included 19−45 patients 22–24 analyzed diagnostic estimates of MRI for non‐organ confined disease in patients with radiorecurrent PCa. In general, it appears that prostate MRI in radiorecurrent PCa achieves slightly worse diagnostic estimates for pT3 disease than in primary PCa staging, which can be attributed to the effect of RT 22–25 .…”

“…Up to now few studies, which included 19−45 patients 22–24 analyzed diagnostic estimates of MRI for non‐organ confined disease in patients with radiorecurrent PCa. In general, it appears that prostate MRI in radiorecurrent PCa achieves slightly worse diagnostic estimates for pT3 disease than in primary PCa staging, which can be attributed to the effect of RT 22–25 . For example, in a study by Kowa et al including 24 patients treated with SRP prostate MRI had sensitivity, specificity, PPV, and NPV of 45%, 96%, 92%, and 68% for pT3b disease 23 .…”

“…In general, it appears that prostate MRI in radiorecurrent PCa achieves slightly worse diagnostic estimates for pT3 disease than in primary PCa staging, which can be attributed to the effect of RT. [22][23][24][25] For example, in a study by Kowa et al including 24 patients treated with SRP prostate MRI had sensitivity, specificity, PPV, and NPV of 45%, 96%, 92%, and 68% for pT3b disease. 23 In a study of Muehlematter et al accuracy of MRI for pT3 for primary setting, was 65%−66%, and was slightly lower than of PSMA-PET (73%−79%).…”

“…[22][23][24][25] For example, in a study by Kowa et al including 24 patients treated with SRP prostate MRI had sensitivity, specificity, PPV, and NPV of 45%, 96%, 92%, and 68% for pT3b disease. 23 In a study of Muehlematter et al accuracy of MRI for pT3 for primary setting, was 65%−66%, and was slightly lower than of PSMA-PET (73%−79%). 25 In our study of 113 patients, these estimates of prostate MRI were similar with the sensitivity of 40%, specificity of 94%, PPV of 83%, NPV of 66%, and accuracy of 70% for pT3 disease.…”