PSMA PET-CT Research Articles

Patterns of failure on Ga PSMA (GaPSMA) and F18 FDG (FDG) PET CT in a prospective phase 2 trial of 177Lu DKFZ PSMA 617 (LuPSMA) in men with castrate resistant metastatic prostate cancer (mCRPC).

2562 Background: LuPSMA is emerging as an effective therapy in mCRPC, with retrospective series reporting high PSA response rates in men undergoing treatment (tx). However, not all men have prolonged tx responses. We report the prospective imaging (GaPSMA/FDG) and PSA response of men who progress biochemically during LuPSMA tx to gain information on characteristics of failure patterns, to determine optimal future tx strategies. Methods: Men with mCRPC, who had failed androgen blockade, failed/ ineligible/refused chemotherapy, with GaPSMA positive disease were enrolled in a prospective phase 2 trial. All men underwent LuPSMA therapy 6-8Gbq, 4 doses at 6 weekly intervals. Imaging with FDG, GaPSMA, bone scan and CT scans was at screening, at subsequent PSA rise, or 3 months post completion of 4 cycles of therapy. Results: 14 men met eligibility criteria and enrolled. 4/14 (28%) men had progressive disease (no PSA response). 10/14 (72%) PSA reduced by a mean 56% .Overall 9/14 (64%) men had >30% decline in PSA, and 5/15(36%) >50% reduction in PSA. 7/15 men were reimaged with GaPSMA, FDG at biochemical failure or 3/12 post tx completion. Imaging revealed 4 distinct patterns (P) of progression. Conclusions: PSMA acts as both target for radionuclide therapy and biomarker for effective tx response. PSMA and FDG imaging at PSA failure following or during LU PSMA therapy identifies phenotypic patterns of failure that have implications for determining next best tx options in men with mCRPC. [Table: see text]

MP20-15 THE ACCURACY OF 68GALLIUM-PSMA PET/CT IN PRIMARY LYMPH NODE STAGING FOR HIGH RISK PROSTATE CANCER

You have accessJournal of UrologyProstate Cancer: Staging I1 Apr 2017MP20-15 THE ACCURACY OF 68GALLIUM-PSMA PET/CT IN PRIMARY LYMPH NODE STAGING FOR HIGH RISK PROSTATE CANCER Can Obek, Tunkut Doganca, Emre Demirci, Meltem Ocak, Ali Riza Kural, Asif Yildirim, Ugur Yucetas, Cetin Demirdag, Sarper M. Erdogan, and Levent Kabasakal Can ObekCan Obek More articles by this author , Tunkut DogancaTunkut Doganca More articles by this author , Emre DemirciEmre Demirci More articles by this author , Meltem OcakMeltem Ocak More articles by this author , Ali Riza KuralAli Riza Kural More articles by this author , Asif YildirimAsif Yildirim More articles by this author , Ugur YucetasUgur Yucetas More articles by this author , Cetin DemirdagCetin Demirdag More articles by this author , Sarper M. ErdoganSarper M. Erdogan More articles by this author , and Levent KabasakalLevent Kabasakal More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2017.02.647AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES PSMA/PET CT is a novel molecular imaging for accurate staging of prostate cancer. Its role has been mostly investigated in post-treatment setting. We assessed the diagnostic accuracy of 68Gallium-PSMA PET to predict LN metastases in primary N-staging in high andvery high-risk non-metastatic prostate cancer in comparison with morphologic imaging. METHODS This was a multi-centric trial of the Society of Urologic Oncology in Turkey in conjunction with Nuclear Medicine Department at Cerrahpasa School of Medicine, Istanbul University. Patients were accrued from 8 centers. High and very high-risk patientsscheduled to undergo surgical treatment with extended LN dissection between July 2014 and October 2015 were included. Morphological imaging was with either MRI/CT. PSMA PET-CT was performed and evaluated at a single center. Sensitivity, specificity and accuracywere calculated for the detection of lymphatic metastases for PSMA PET/CT and morphological imaging. Kappa values were calculated for pathological and radiological incidence of LN metastases. RESULTS Data on 51 eligible patients are presented. Sensitivity, specificity and accuracy of PSMA PET to detect LN metastases in primary setting were 53%, 86%, and 76% and increased to 67%, 88% and 81% in a sub-group with =15 LN removed. Kappa values for correlation of imaging and pathology was 0.41 for PSMA PET and 0.18 for morphological imaging. CONCLUSIONS PSMA/PET CT is superior to morphological imaging for the detection of metastatic LNs in primary prostate cancer setting. Surgical dissection remains to be the gold standard for precise lymphatic staging. © 2017FiguresReferencesRelatedDetails Volume 197Issue 4SApril 2017Page: e244-e245 Advertisement Copyright & Permissions© 2017MetricsAuthor Information Can Obek More articles by this author Tunkut Doganca More articles by this author Emre Demirci More articles by this author Meltem Ocak More articles by this author Ali Riza Kural More articles by this author Asif Yildirim More articles by this author Ugur Yucetas More articles by this author Cetin Demirdag More articles by this author Sarper M. Erdogan More articles by this author Levent Kabasakal More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Imaging: PSMA PET-CT in initial prostate cancer staging.

The speed with which PSMA PET–CT has been adopted for prostate cancer imaging is unprecedented. This technique's clinical value in recurrent disease is uncontested, but its role in initial staging is unclear. Two studies now provide important data on the value of PSMA PET–CT at this management stage.

The Current Status of PSMA PET-CT for Evaluating Biochemical PSA Relapse in Prostate Cancer

In the curative treatment of prostate cancer (PC), up to 40 % of PC cases may suffer disease recurrence depending on their prognostic factors. In these men, monitoring with prostate-specific antigen (PSA) testing may herald this event but it does not provide information on the site or extent of PC recurrence. It remains important to have an imaging modality that can detect disease recurrence at the earliest stage when disease may still be local or regional and radical ablative therapies could provide recurrence salvage or to reliably exclude patients from unnecessary therapy when there is evidence of distant micrometastatic disease. Functional imaging can provide improved detection over conventional imaging with CT, MRI and bone scanning. Choline PET has been reported to have higher PC detection sensitivity than FDG-PET but this falls with lower PSA values. PSMA PET has been reported to provide greater sensitivity and specificity particularly with lower PSA, i.e. <0.5–1 and may yield greater utility to quantify the relapse status of PC men. This article will review the status of PSMA PET-CT for PSA recurrences following PC treatment.

WbMRI to detect bone metastases: critical review on diagnostic accuracy and comparison to other imaging modalities

Numerous imaging modalities are available for the diagnosis of bone metastases (BM) in patients with cancer. This paper reviews published studies comparing whole-body (wb) MRI to BS, PET or PET-CT to provide up-to-date evaluation of the diagnostic accuracy of wbMRI to detect BM. This review is based on a systematic search of the literature of studies evaluating the diagnostic performance of wbMRI for BM detection. Evidence synthesis was achieved via a classification tree, which provides an overview of the performance of the different imaging techniques and of the context in which these are assessed, and an evidence table to seek confirmation of the diagnostic value of the imaging techniques. Eligible studies (n = 23/301) included patients with cancer who underwent wbMRI for suspicion of BM or for systematic cancer staging, compared with at least one other imaging tool. The evidence supporting the superiority of wbMRI over BS for BM screening is strong. wbMRI with diffusion-weighted imaging (DWI) sequence has higher sensitivity than wbMRI alone. The respective accuracies of wbMRI and FDG PET-CT differ depending both on the type of analysis (lesion, region or patient-based) and primary cancer. wbMRI and PET-CT emerge as the techniques of choice for the diagnosis of BM. The inclusion of DWI in wbMRI protocols is of value to optimize the sensitivity but does not add in specificity. This indicates the importance of the anatomical sequences in those protocols. Further comparisons between wbMRI and DWI alone, 18F-NaF, 11C-Choline, PSMA PET-CT and PET-MRI systems remain necessary.

TONSILLECTOMY

<b>Background:</b> Multi-parametric magnetic resonance imaging (mpMRI) is validated for the diagnosis of clinically significant prostate cancer (csPCa). ⁶⁸Ga-PSMA -11 PET/CT (PSMA-PET/CT) combined with mpMRI has improved negative predictive value over mpMRI alone for csPCa. The aim of this post-hoc analysis of the PRIMARY study was to evaluate the clinical significance of patterns of intra-prostatic PSMA activity, proposing a 5- point PRIMARY score to optimise accuracy of PSMA-PET/CT for csPCa in a low prevalence population. <b>Methods:</b> The PRIMARY trial is a prospective multi-centre phase II imaging trial that enrolled biopsy-naïve men with suspected PCa, no prior biopsy, recent mpMRI (6 months) and planned for prostate biopsy. 291 men underwent mpMRI, PSMA-PET/CT and systematic +/- targeted biopsy. The mpMRI was read separately using PI-RADS (V2). PSMA-PET/CT (pelvic only) was acquired a minimum 60 minutes post injection. PSMA-PET/CT was centrally read for pattern (diffuse transition zone (TZ), symmetrical central zone (CZ), focal TZ or peripheral zone (PZ), and intensity (SUV_max). In this post-hoc analysis, a 5-level PRIMARY score was assigned based on analysis of the central read: 1. No pattern, 2. Diffuse TZ or CZ (no focal), 3. Focal TZ, 4. Focal PZ or 5. SUV_max ≥ 12. Two further readers independently assigned a PRIMARY score to 118 scans for inter-rater agreement. Associations between PRIMARY score and csPCa (ISUP≥2) were evaluated. <b>Results:</b> Of 291 men enrolled, 162 (56%) had csPCa. PRIMARY score-1 was present in 16% (47), score-2 in 19% (55), score-3 in 10% (29), score-4 in 40% (117) and score-5 in 15% (43). The proportion of patients with csPCa and PRIMARY score 1 to 5 was 8.5% (4/47), 27% (15/55), 38% (11/29), 76% (89/117) and 100% (43/43) respectively. Sensitivity, specificity, PPV and NPV for PRIMARY score 1,2 (low-risk patterns) vs PRIMARY score 3-5 (high-risk patterns) was 88%, 64%, 76% and 81%, compared to 83%, 53%, 69% and 72% for PI-RADS (2 vs 3-5) on mpMRI. The inter-rater agreements for PRIMARY score 1,2 vs. PRIMARY score 3-5 was 0.76 (CI: 0.64-0.88) and 0.64 (CI: 0.49-0.78). <b>Conclusion:</b> A PRIMARY score incorporating intra-prostatic pattern and intensity on PSMA-PET/CT shows potential with high diagnostic accuracy for csPCa. Further validation is warranted prior to implementation.