Prostate-specific membrane antigen (PSMA) fusion imaging in prostate cancer: PET–CT vs PET–MRI

Abstract

Objectives: To investigate whether PET/CT or PET/MRI is more appropriate for imaging prostate cancer, in terms of for primary tumor detection, local staging and recurrence, as well as lymph nodes and distant metastases. Methods: A systematic literature search was conducted on Embase, PubMed/MEDLINE, and the Cochrane Library database. Studies evaluating the diagnostic performance of PET/CT vs PET/MRI in prostate cancer patients were emphasized. Results: We reviewed 57 original research articles during the period 2016—2021: 14 articles regarding the radiotracer PSMA; 18 articles regarding the primary tumor detection, local tumor staging, managing local recurrence; 17 articles for managing lymph node metastases; and eight articles for managing bone and other distant metastases. PSMA PET could be complementary to mpMRI for primary prostate cancer localization and is particularly valuable for PI-RADS three lesions. PET/MRI is better than PET/CT in local tumor staging due to its specific benefit in predicting extracapsular extension in MRI-occult prostate cancer patients. PET/MRI is likely superior as compared with PET/CT in detecting local recurrence, and have slightly higher detection rates than PET/CT in lymph node recurrence. PET/CT and PET/MRI seem to have equivalent performance in detecting distant bony or visceral metastases. Conclusion: In conclusion, PET/MRI is suitable for local and regional disease, either primary staging or restaging whereas PET/CT is valuable for managing distant bony or visceral metastasis. Advances in knowledge: We reviewed the emerging applications of PET/MRI and PET/CT in clinical aspects. Readers will gain an objective overview on the strength and shortfalls of PET/MRI or PET/CT in the management of prostate cancer.

Value of Targeted Biopsies and Combined PSMA PET/CT and mp-MRI Imaging in Locally Recurrent Prostate Cancer after Primary Radiotherapy

“…To the best of our knowledge, there are no previous studies focusing on the accuracy of combined PSMA PET/CT and mp-MRI imaging in the radiorecurrent setting, with MR-targeted histopathological confirmation available. Previous studies have examined the diagnostic accuracy of PSMA PET/CT or mp-MRI in recurrent prostate cancer, but not in the same setting as in our study, because of differences in primary treatment (all or a subgroup of patients with status after primary prostatectomy or HIFU), location of biopsies (i.e., biopsies of regional or distant metastases), biopsy type (not MR-targeted), or imaging (not a combination of PSMA PET/CT and mp-MRI) [17,36,40,[43][44][45][46][47][48].…”

“…In the diagnostic setting before primary treatment of local disease, PPVs between 36 and 100% for PSMA PET/CT [33][34][35][36][37], 34 and 85% for mp-MRI [33][34][35]38], and 67 and 85% [35,39] for combined PSMA PET/CT and mp-MRI are reported. Sensitivity and specificity rates between 64 and 95% and 71 and 95% have been found for PSMA PET/CT and between 67 and 96% and 81 and 100% for PSMA PET/MRI in primary prostate cancer detection [40,41]. For mp-MRI alone, sensitivity rates of 43-96% and specificity rates of 23-98% have been described elsewhere [38,40,41].…”

“…Sensitivity and specificity rates between 64 and 95% and 71 and 95% have been found for PSMA PET/CT and between 67 and 96% and 81 and 100% for PSMA PET/MRI in primary prostate cancer detection [40,41]. For mp-MRI alone, sensitivity rates of 43-96% and specificity rates of 23-98% have been described elsewhere [38,40,41].…”

“…This is a new, small, but expanding subgroup of patients that is not adequately covered in our study to infer conclusions on. Integrated PET/MRI imaging also seems promising and might be used in radiorecurrent prostate cancer [40,57].…”

The survival benefit of different lymph node yields in radical prostatectomy for pN1M0 prostate cancer patients: Implications from a population-based study

“…Imaging results such as CT/PET-CT and multiparametric MRI/PET-MRI had low sensitivity in identifying lymph node metastases ( 24 , 25 ). Nomograms had been built for predicting lymph node metastases ( 2 , 6 ); these tools also mainly relied on Gleason score and T stage, and we found that the two factors had an impact on the survival benefit of LND, and that extended LND was more likely to remove occult lymph node metastases, as higher Gleason score and T stage were risk factors for lymph node metastasis ( 26 – 28 ).…”