Prostate-specific Membrane Antigen Positron Emission Tomography/computed Tomography Research Articles

Prediction of Lesion-Based Treatment Response after Two Cycles of Lu-177 Prostate Specific Membrane Antigen Treatment in Metastatic Castration-Resistant Prostate Cancer Using Machine Learning

Introduction: Lutetium-177 (Lu-177) prostate-specific membrane antigen (PSMA) therapy is a radionuclide treatment that prolongs overall survival in metastatic castration-resistant prostate cancer (MCRPC). We aimed to predict lesion-based treatment response after Lu-177 PSMA treatment using machine learning with texture analysis data obtained from pretreatment Gallium-68 (Ga-68) PSMA positron emission tomography/computed tomography (PET/CT). Methods: Eighty-three progressed, and 91 nonprogressed malignant foci on pretreatment Ga-68 PSMA PET/CT of 9 patients were used for analysis. Malignant foci with at least a 30% increase in Ga-68 PSMA uptake after two cycles of treatment were considered progressed lesions. All other changes in Ga-68 PSMA uptake of the lesions were considered nonprogressed lesions. The classifiers tried to predict progressed lesions. Results: Logistic regression, Naive Bayes, and k-nearest neighbors’ area under the ROC curve (AUC) values in detecting progressed lesions in the training group were 0.956, 0.942, and 0.950, respectively, and their accuracy was 87%, 85%, and 89%, respectively. The AUC values of the classifiers in the testing group were 0.937, 0.954, and 0.867, respectively, and their accuracy was 85%, 88%, and 79%, respectively. Conclusion: Using machine learning with texture analysis data obtained from pretreatment Ga-68 PSMA PET/CT in MCRPC predicted lesion-based treatment response after two cycles of Lu-177 PSMA treatment.

Prediction of biochemical recurrence after radical prostatectomy from primary tumour characteristics.

To construct and externally calibrate a predictive model for early biochemical recurrence (BCR) after radical prostatectomy (RP) incorporating clinical and modern imaging characteristics of the primary tumour. Patients who underwent RP following multiparametric magnetic resonance imaging, prostate biopsy and prostate-specific membrane antigen-positron emission tomography/computed tomography (PSMA-PET/CT), from two centres in Australia and the Netherlands. The primary outcome was biochemical recurrence-free survival (BRFS), where BCR was defined as a rising PSA level of ≥0.2 ng/mL or initiation of postoperative treatment per clinician discretion. Proportional hazards models to predict time to event were developed in the Australian sample using relevant pre- and post-surgical parameters and primary tumour maximum standardised uptake value (SUVmax) on diagnostic PSMA-PET/CT. Calibration was assessed in an external dataset from the Netherlands with the same inclusion criteria. Data from 846 patients were used to develop the models. Tumour SUVmax was associated with worse predicted 3-year BRFS for both pre- and post-surgical models. SUVmax change from 4 to 16 lessened the predicted 3-year BRFS from 66% to 42% for a patient aged 65 years with typical pre-surgical parameters (PSA level 8 ng/mL, Prostate Imaging-Reporting and Data System score 4/5 and biopsy Gleason score ≥4 + 5). Considering post-surgical variables, a patient with the same age and PSA level but pathological stage pT3a, RP Gleason score ≥4 + 5 and negative margins, SUVmax change from 4 to 16 lessened the predicted 3-year BRFS from 76% to 61%. Calibration on an external sample (n = 464) showed reasonable performance; however, a tendency to overestimate survival in patients with good prognostic factors was observed. Tumour SUVmax on diagnostic PSMA-PET/CT has utility additional to commonly recognised variables for prediction of BRFS after RP.

Whole pelvis vs. hemi pelvis elective nodal radiotherapy in patients with PSMA-positive nodal recurrence after radical prostatectomy - a retrospective multi-institutional propensity score analysis

PurposeDespite growing evidence for bilateral pelvic radiotherapy (whole pelvis RT, WPRT) there is almost no data on unilateral RT (hemi pelvis RT, HPRT) in patients with nodal recurrent prostate cancer after prostatectomy. Nevertheless, in clinical practice HPRT is sometimes used with the intention to reduce side effects compared to WPRT. Prostate-specific membrane antigen positron emission tomography / computed tomography (PSMA-PET/CT) is currently the best imaging modality in this clinical situation. This analysis compares PSMA-PET/CT based WPRT and HPRT.MethodsA propensity score matching was performed in a multi-institutional retrospective dataset of 273 patients treated with pelvic RT due to nodal recurrence (214 WPRT, 59 HPRT). In total, 102 patients (51 in each group) were included in the final analysis. Biochemical recurrence-free survival (BRFS) defined as prostate specific antigen (PSA) < post-RT nadir + 0.2ng/ml, metastasis-free survival (MFS) and nodal recurrence-free survival (NRFS) were calculated using the Kaplan-Meier method and compared using the log rank test.ResultsMedian follow-up was 29 months. After propensity matching, both groups were mostly well balanced. However, in the WPRT group there were still significantly more patients with additional local recurrences and biochemical persistence after prostatectomy. There were no significant differences between both groups in BRFS (p = .97), MFS (p = .43) and NRFS (p = .43). After two years, BRFS, MFS and NRFS were 61%, 86% and 88% in the WPRT group and 57%, 90% and 82% in the HPRT group, respectively. Application of a boost to lymph node metastases, a higher RT dose to the lymphatic pathways (> 50 Gy EQD2α/β=1.5 Gy) and concomitant androgen deprivation therapy (ADT) were significantly associated with longer BRFS in uni- and multivariate analysis.ConclusionsOverall, this analysis presents the outcome of HPRT in nodal recurrent prostate cancer patients and shows that it can result in a similar oncologic outcome compared to WPRT. Nevertheless, patients in the WPRT may have been at a higher risk for progression due to some persistent imbalances between the groups. Therefore, further research should prospectively evaluate which subgroups of patients are suitable for HPRT and if HPRT leads to a clinically significant reduction in toxicity.

Improving sensitivity through data augmentation with synthetic lymph node metastases for AI-based analysis of PSMA PET-CT images.

We developed a fully automated artificial intelligence(AI)AI-based-based method for detecting suspected lymph node metastases in prostate-specific membrane antigen (PSMA)(PSMA) positron emission tomography-computed tomography (PET-CT)(PET-CT) images of prostate cancer patients by using data augmentation that adds synthetic lymph node metastases to the images to expand the training set. Synthetic data were derived from original training images to which new synthetic lymph node metastases were added. Thus, the original training set from a previous study (n = 420) was expanded by one synthetic image for every original image (n = 840), which was used to train an AI model. The performance of the AI model was compared to that of nuclear medicine physicians and a previously developed AI model. The human readers were alternately used as a reference and compared to either another reading or AI model. The new AI model had an average sensitivity of 84% for detecting lymph node metastases compared with 78% for human readings. Our previously developed AI method without synthetic data had an average sensitivity of 79%. The number of false positive lesions were slightly higher for the new AI model (average 3.3 instances per patient) compared to human readings and the previous AI model (average 2.8 instances per patient), while the number of false negative lesions was lower. Creating synthetic lymph node metastases, as a form of data augmentation, on [18F]PSMA-1007F]PSMA-1007 PETPET-CT-CT images improved the sensitivity of an AI model for detecting suspected lymph node metastases. However, the number of false positive lesions increased somewhat.

Reliability and practicability of PSMA-RADS 1.0 for structured reporting of PSMA-PET/CT scans in prostate cancer patients

ObjectivesAs structured reporting is increasingly used in the evaluation of prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA-PET/CT) for prostate cancer, there is a need to assess the reliability of these frameworks. This study aimed to evaluate the intra- and interreader agreement among readers with varying levels of experience using PSMA-RADS 1.0 for interpreting PSMA-PET/CT scans, even when blinded to clinical data, and therefore to determine the feasibility of implementing this reporting system in clinical practice.MethodsPSMA-PET/CT scans of 103 patients were independently evaluated by 4 readers with different levels of experience according to the reporting and data system (RADS) for PSMA-PET/CT imaging PSMA-RADS 1.0 at 2 time points within 6 weeks. For each scan, a maximum of five target lesions were freely chosen and stratified according to PSMA-RADS 1.0. Overall scan score and compartment-based scores were assessed. Intra- and interreader agreement was determined using the intraclass correlation coefficient (ICC).ResultsPSMA-RADS 1.0 demonstrated excellent interreader agreement for both overall scan scores (ICC ≥ 0.91) and compartment-based scores (ICC ≥ 0.93) across all four readers. The framework showed excellent intrareader agreement for overall scan scores (ICC ≥ 0.86) and compartment-based scores (ICC ≥ 0.95), even among readers with varying levels of experience.ConclusionsPSMA-RADS 1.0 is a reliable method for assessing PSMA-PET/CT with strong consistency and agreement among readers. It shows great potential for establishing a standard approach to diagnosing and planning treatment for prostate cancer patients, and can be used confidently even by readers with less experience.Clinical relevance statementThis study underlines that PSMA-RADS 1.0 is a valuable and highly reliable scoring system for PSMA-PET/CT scans of prostate cancer patients and can be used confidently by radiologists with different levels of experience in routine clinical practice.Key PointsPSMA-RADS version 1.0 is a scoring system for PSMA-PET/CT scans. Its reproducibility needs to be analyzed in order to make it applicable to clinical practice.Excellent interreader and intrareader agreement for overall scan scores and compartment-based scores using PSMA-RADS 1.0 were seen in readers with varying levels of experience.PSMA-RADS 1.0 is a reliable tool for accurately diagnosing and planning treatment for prostate cancer patients, and can be used confidently in clinical routine.

Biochemically recurrent prostate cancer: rationalisation of the approach to imaging

To assess the utility of magnetic resonance imaging (MRI) in addition to the additive benefit of the conventional imaging techniques, computed tomography (CT) and nuclear medicine (NM) bone scintigraphy, for investigation of biochemical recurrence (BCR) post-prostatectomy where access to prostate specific membrane antigen (PSMA) positron-emission tomography (PET)-CT is challenging. Relevant imaging over a 5-year period was reviewed. Ethical approval was granted by the internal review board. All patients with suspected BCR, defined as a PSA ≥0.2 ng/ml on two separate occasions, underwent a retrospective imaging review. This was performed on PACS archive search database in a single centre using search terms "PSA" and "prostatectomy" in the three imaging methods; MRI, CT, and NM bone scintigraphy. All PSMA PET CT performed were recorded. One hundred and eighty-five patients were identified. Patients with an MRI pelvis that demonstrated distant metastases (i.e., pelvic bone metastases or lymph node involvement more cranial to the bifurcation of the common iliac arteries) were more likely to have a positive CT and/or NM bone scintigraphy. The Pearson correlation coefficient between the findings of M1 disease at MRI pelvis and the presence of distant metastases at CT thorax, abdomen, pelvis and NM bone scintigraphy was calculated at 0.81 (p<0.01) and 0.91 (p<0.01) respectively. An imaging strategy based on risk stratification and technique-specific selection criteria leads to more appropriate use of resources, and in turn, increases the yield of conventional imaging methods. MRI prostate findings can be used to predict the additive value of CT/NM bone scintigraphy allowing a more streamlined approach to their use.

DEPROMP Trial: the additive value of PSMA-PET/CT-guided biopsy for prostate cancer management in biopsy naïve men—study protocol for a randomized trial

BackgroundThe primary objective is to determine the proportion of men with suspected prostate cancer (PCA) in whom the management plans are changed by additive gallium-68 prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA-PET/CT) guided prostate biopsy (PET-TB) in combination with standard of care (SOC) using systematic (SB) and multiparametric magnetic resonance imaging-guided biopsy (MR-TB) compared with SOC alone. The major secondary objectives are to determine the additive value of the combined approach of SB + MR-TB + PET-TB (PET/MR-TB) for detecting clinically significant PCA (csPCA) compared to SOC; to determine sensitivity, specificity, positive and negative predictive value and diagnostic accuracy of imaging techniques, respective imaging classification systems, and each biopsy method; and to compare preoperatively defined tumor burden and biomarker expression and pathological tumor extent in prostate specimens.MethodsThe DEPROMP study is a prospective, open-label, interventional investigator-initiated trial. Risk stratification and management plans after PET/MR-TB are conducted randomized and blinded by different evaluation teams of experienced urologists based on histopathological analysis and imaging information: one including all results of the PET/MR-TB and one excluding the additional information gained by PSMA-PET/CT guided biopsy. The power calculation was centered on pilot data, and we will recruit up to 230 biopsy-naïve men who will undergo PET/MR-TB for suspected PCA. Conduct and reporting of MRI and PSMA-PET/CT will be performed in a blinded fashion.DiscussionThe DEPROMP Trial will be the first to evaluate the clinically relevant effects of the use of PSMA-PET/CT in patients with suspected PCA compared to current SOC. The study will provide prospective data to determine the diagnostic yields of additional PET-TB in men with suspected PCA and the impact on treatment plans in terms of intra- and intermodal changes. The results will allow a comparative analysis of risk stratification by each biopsy method, including a performance analysis of the corresponding rating systems. This will reveal potential intermethod and pre- and postoperative discordances of tumor stage and grading, providing the opportunity to critically assess the need for multiple biopsies.Trial registrationGerman Clinical Study Register DRKS 00024134. Registered on 26 January 2021.

Unexpected Metastatic Localizations of Prostate Cancer Determined by 68Ga PSMA PET/CT: Series of Four Cases.

Prostate-specific membrane antigen (PSMA) is a transmembrane protein with overexpression in most prostate cancer cells. Gallium-68-(68Ga) PSMA positron emission tomography/computed tomography (PET/CT) imaging is a game-changer in the management of prostate cancer. 68Ga PSMA PET/CT scan is advanced and a promising radioligand has high sensitivity in determining lesions of prostate cancer with a high tumor to background ratio. The most common areas of metastasis are the bone and pelvic lymph nodes. The prognosis of prostate cancer is mainly determined by the status of metastases. The presence and the localization of metastases affects treatment planning. In our cases, we presented some examples of uncommon sites of metastases such as the brain, adrenal glands, penis and orbit. Improvements in imaging techniques, such as 68Ga PSMA PET/CT have led to the possibility to make more determi nation of rare metastase sites in prostate cancer patients.

Prostate-specific membrane antigen (PSMA) positron emission tomography (PET) compared to computed tomography (CT) for advanced renal cell carcinoma (RCC).

4540 Background: There is emerging role of the use of PSMA PET in RCC. Herein, we report our experience in use of PSMA PET in recurrent or metastatic RCC in Brisbane, Australia. Methods: Patients (pts) who underwent PSMA PET and conventional diagnostic CT for metastatic or recurrent RCC between 2015 and 2020 at three institutions were identified. Retrospective chart reviews were conducted using standardized collection template. The outcomes included percentage of patients who had a change in management secondary to PSMA PET findings, comparison of metastasis detection for PSMA PET vs. CT, and biopsy histology of PSMA avid sites. Results: 42 PSMA PET were performed in 40 patients. 10 pts (25%) and 30 pts (75%) had PSMA PET in the metastatic disease and recurrent disease setting, respectively. Table 1 highlights demographics. Overall, 12 pts (30%, n=3 metastatic, n=9 recurrent) had a change in management following PSMA PET. In the metastatic disease group, 2 pts (20%) underwent initial systemic therapy (after histological confirmation) due to higher burden of disease shown with PSMA PET than CT, while systemic therapy was changed for 1 pt (10%). In the recurrent disease group, PSMA improved delineation of suspected recurrence (compared to CT) resulting in resection rather than surveillance (n=4; 13%) or change in surgical approach for resection (n=1; 3%). PSMA PET distribution showed more metastatic sites than CT leading to systemic therapy rather than resection of recurrence (n=2; 7%), while absent PSMA activity for suspected recurrence on CT led to surveillance rather than resection (n=2; 7%). PSMA PET detected more sites of metastases compared with conventional scan in 6 pts (60%) with metastatic disease and in 9 pts (30%) with recurrent disease. 26 pts had biopsy of PSMA avid sites. Majority of pts had confirmed recurrence of clear cell renal carcinoma (n= 22; 85%). Other histology included sarcomatoid renal cell carcinoma (n=2; 8%), carcinoid (n=1; 4%), and urothelial cancer (n=1; 4%). In 2 instances, biopsy/resection was performed of a suspected recurrence on CT that was not PSMA avid, and neither showed malignancy. Conclusions: PSMA PET detected more accurately metastatic and recurrent disease, with high pathological concordance, to result in change in management for 30% of patients. Prospective study is warranted to further investigate the utility of PSMA PET scan in advanced RCC.[Table: see text]

PSMA PET-CT Imaging Predicts Treatment Progression in Men with Biochemically Recurrent Prostate Cancer-A Prospective Study of Men with 3 Year Follow Up.

Simple SummaryProstate-specific membrane antigen (PSMA) positron emission tomography-computed tomography (PET-CT) is an essential imaging tool that is used to locate prostate cancer when it recurs. The results of this scan are used to guide clinical decisions for the management of cancer. However, the long-term effect of these clinical decisions is yet to be determined. In this study, we followed men with recurrent prostate cancer for 3 years after they had a clinical decision made based on a PSMA PET-CT. Our results showed that 75% of men had no addition or change in their treatment plan 3 years after their initial clinical decision was made. In men with a PSMA PET-CT that showed no suspected cancer, 85% had no addition or change to their treatment plan. This indicates that clinical decisions made using PSMA PET-CT in this setting can have a medium- to long-lasting effect.Prostate-specific membrane antigen (PSMA) positron emission tomography-computed tomography (PET-CT) is a novel imaging modality used to stage recurrent prostate cancer. It has the potential to improve prognostication and ultimately guide the timing of treatment for men with recurrent prostate cancer. This study aims to assess the clinical impact of PSMA PET-CT by analyzing its predictive value of treatment progression after 3 years of follow-up. In this prospective cohort study of 100 men, patients received a PSMA PET-CT for restaging of their disease which was used by a multi-disciplinary team to make a treatment decision. The primary endpoint was treatment progression. This was defined as the addition or change of any treatment modalities such as androgen deprivation therapy (ADT), radiation therapy or chemotherapy. The median follow-up time was 36 months (IQR 24–40 months). No treatment progression was found in 72 (75%) men and therefore 24 (25%) patients were found to have treatment progression. In men with a negative PSMA PET-CT result, 5/33 (15.1%) had treatment progression and 28/33 (84.8%) had no treatment progression. In conclusion, clinical decisions made with PSMA PET-CT results led to 75% of men having no treatment progression at 3 years of follow-up. In men with negative PSMA PET-CT results, this increased to 85% of men.

Targeting PSMA Revolutionizes the Role of Nuclear Medicine in Diagnosis and Treatment of Prostate Cancer.

Simple SummaryImaging plays a crucial role in the accurate staging of prostate cancer. Prostate-specific membrane antigen (PSMA) is overexpressed in prostate cancer cells, and targeting the PSMA protein for diagnostic purposes has become of great clinical value. Another valuable feature of PSMA is its opportunity to serve as a target for delivering radionuclide therapy to cancer cells. PSMA-ligands can be labeled with various radionuclides, such as alpha and beta-emitters. This review offers an overview of the literature on recent developments in nuclear medicine regarding PSMA in prostate cancer diagnostics and targeted radionuclide therapy.Targeting the prostate-specific membrane antigen (PSMA) protein has become of great clinical value in prostate cancer (PCa) care. PSMA positron emission tomography/computed tomography (PET/CT) is increasingly used in initial staging and restaging at biochemical recurrence in patients with PCa, where it has shown superior detection rates compared to previous imaging modalities. Apart from targeting PSMA for diagnostic purposes, there is a growing interest in developing ligands to target the PSMA-protein for radioligand therapy (RLT). PSMA-based RLT is a novel treatment that couples a PSMA-antibody to (alpha or beta-emitting) radionuclide, such as Lutetium-177 (177Lu), to deliver high radiation doses to tumor cells locally. Treatment with 177Lu-PSMA RLT has demonstrated a superior overall survival rate within randomized clinical trials as compared to routine clinical care in patients with metastatic castration-resistant prostate cancer (mCRPC). The current review provides an overview of the literature regarding recent developments in nuclear medicine related to PSMA-targeted PET imaging and Theranostics.

Comparison of 68Ga-Prostate Specific Membrane Antigen (PSMA) Positron Emission Tomography Computed Tomography (PET-CT) and Whole-Body Magnetic Resonance Imaging (WB-MRI) with Diffusion Sequences (DWI) in the Staging of Advanced Prostate Cancer.

Simple SummaryPrecise staging is key for the optimal management of advanced prostate cancer. PSMA PET-CT and WB-MRI outperform standard imaging technology for staging high-risk prostate cancer, but direct comparison between both modalities is lacking. The primary endpoint of our study was to compare the diagnostic accuracy of both techniques in the detection of lymph node, bone and visceral metastases against a best valuable comparator (BVC), defined as a consensus adjudication of all lesions on the basis of baseline and follow-up imaging, biological and clinical data and histopathologic confirmation when available. Knowing the diagnostic accuracy of both next generation imaging modalities might influence the diagnostic and therapeutic strategy in prostate cancer by tailoring therapy. However, the impact on treatment and patient outcome of an improved detection of metastases has not been determined yet.Background: Prostate specific membrane antigen (PSMA) positron emission tomography computed tomography (PET-CT) and whole-body magnetic resonance imaging (WB-MRI) outperform standard imaging technology for the detection of metastasis in prostate cancer (PCa). There are few direct comparisons between both modalities. This paper compares the diagnostic accuracy of PSMA PET-CT and WB-MRI for the detection of metastasis in PCa. One hundred thirty-four patients with newly diagnosed PCa (n = 81) or biochemical recurrence after curative treatment (n = 53) with high-risk features prospectively underwent PSMA PET-CT and WB-MRI. The diagnostic accuracy of both techniques for lymph node, skeletal and visceral metastases was compared against a best valuable comparator (BVC). Overall, no significant difference was detected between PSMA PET-CT and WB-MRI to identify metastatic patients when considering lymph nodes, skeletal and visceral metastases together (AUC = 0.96 (0.92–0.99) vs. 0.90 (0.85–0.95); p = 0.09). PSMA PET-CT, however, outperformed WB-MRI in the subgroup of patients with newly diagnosed PCa for the detection of lymph node metastases (AUC = 0.96 (0.92–0.99) vs. 0.86 (0.79–0.92); p = 0.0096). In conclusion, PSMA PET-CT outperforms WB-MRI for the detection of nodal metastases in primary staging of PCa.

MP11-14 VERY LOW PROSTATE PET CT PSMA EXPRESSION MAY BE MISLEADING IN STAGING PROSTATECTOMY CANDIDATES

You have accessJournal of UrologyProstate Cancer: Staging (MP11)1 Sep 2021MP11-14 VERY LOW PROSTATE PET CT PSMA EXPRESSION MAY BE MISLEADING IN STAGING PROSTATECTOMY CANDIDATES Rennen Haramaty, Alon Lazarovich, Asaf Shvero, Miki Haifler, Jonathan Gal, Shay Golan, Sagi Shpitzer, Azik Hoffman, Omri Nativ, Yuval Freifeld, Rani Zreik, Zohar Dotan, and Barak Rosenzweig Rennen HaramatyRennen Haramaty More articles by this author , Alon LazarovichAlon Lazarovich More articles by this author , Asaf ShveroAsaf Shvero More articles by this author , Miki HaiflerMiki Haifler More articles by this author , Jonathan GalJonathan Gal More articles by this author , Shay GolanShay Golan More articles by this author , Sagi ShpitzerSagi Shpitzer More articles by this author , Azik HoffmanAzik Hoffman More articles by this author , Omri NativOmri Nativ More articles by this author , Yuval FreifeldYuval Freifeld More articles by this author , Rani ZreikRani Zreik More articles by this author , Zohar DotanZohar Dotan More articles by this author , and Barak RosenzweigBarak Rosenzweig More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000001984.14AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: 68Ga-labeled prostate-specific membrane antigen (PSMA) positron-emission tomography (PET) computed tomography (CT) imaging quickly earns an important role in staging radical prostatectomy candidates. While PSMA is generally weakly expressed in normal prostate tissue, it is strongly upregulated in prostate cancer. However, some clinically significant prostate cancers exemplify low reads on PSMA PET CT. In the current work we evaluate this unique sub-population of patients with ‘negative’ prostate PSMA PET CT reads. METHODS: We retrospectively reviewed 392 patients who underwent radical prostatectomy between September 2014 to July 2019 in 5 medical centres.Patients with pre-operative PSMA PET CT imaging were included. We collected data on baseline characteristics including demographics, comorbidities, prostate specific antigen (PSA) and rectal exam, prior biopsies, imaging results, and biopsies and radical prostatectomy histology. An index group of patients with ‘negative’ PSMA PET CT prostate read was defined as “scarce” uptake and/or numerically maximal standardized uptake value (SUVmax) below physiologic uptake. For control we used patients with PSMA PET CT prostate read defined as “intense” and/or numerically as SUVmax above physiologic uptake. RESULTS: 97 patients had PSMA PET CT imaging prior surgery, 52 (54%) of whom fitted with the index group inclusion criteria and 45 (46%) with the control group. All pre-operative characteristics did not significantly differ in-between groups except lesion size and SUVmax per PSMA PET CT (Table1). Prostatectomy specimen’s histology analysis significantly differed in-between groups, for ISUP score, seminal vesicles invasion, T stage and positive margins rates (p<0.05).Nonetheless, 50 (96%) of the index group patients harbored clinically significant disease (ISUP>=2) with extra-prostatic disease showed in 24 (46%) and peri-neural invasion in 35 (67%).Positive lymph nodes were found in 4 (8%) of index group patients. CONCLUSIONS: While prostate cancer aggressiveness was generally correlated with intense uptake of PSMA on pre-operative PSMA/PET CT, a subpopulation of patients with clinically significant cancer and aggressive characteristics show weak reads only on this imaging. These data raise concern applying PSMA PET CT for staging of prostatectomy candidates. Source of Funding:- © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e184-e184 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Rennen Haramaty More articles by this author Alon Lazarovich More articles by this author Asaf Shvero More articles by this author Miki Haifler More articles by this author Jonathan Gal More articles by this author Shay Golan More articles by this author Sagi Shpitzer More articles by this author Azik Hoffman More articles by this author Omri Nativ More articles by this author Yuval Freifeld More articles by this author Rani Zreik More articles by this author Zohar Dotan More articles by this author Barak Rosenzweig More articles by this author Expand All Advertisement Loading ...

MP26-04 STANDARDIZED UPTAKE VALUES AS DETERMINED ON PROSTATE-SPECIFIC MEMBRANOUS ANTIGEN POSITRON EMISSION TOMOGRAPHY/COMPUTER TOMOGRAPHY ARE ASSOCIATED WITH GLEASON GRADE AND BIOCHEMICAL RECURREANCE OF DISEASE IN PATIENTS WITH PROSTATE CANCER

You have accessJournal of UrologyProstate Cancer: Detection & Screening II (MP26)1 Sep 2021MP26-04 STANDARDIZED UPTAKE VALUES AS DETERMINED ON PROSTATE-SPECIFIC MEMBRANOUS ANTIGEN POSITRON EMISSION TOMOGRAPHY/COMPUTER TOMOGRAPHY ARE ASSOCIATED WITH GLEASON GRADE AND BIOCHEMICAL RECURREANCE OF DISEASE IN PATIENTS WITH PROSTATE CANCER Yves Bodar, Hans Veerman, Katelijne de Bie, Dennie Meijer, Pim van Leeuwen, Maarten Donswijk, Harry Hendrikse, Ronald Boellaard, Daniela Oprea-Lager, and André Vis Yves BodarYves Bodar More articles by this author , Hans VeermanHans Veerman More articles by this author , Katelijne de BieKatelijne de Bie More articles by this author , Dennie MeijerDennie Meijer More articles by this author , Pim van LeeuwenPim van Leeuwen More articles by this author , Maarten DonswijkMaarten Donswijk More articles by this author , Harry HendrikseHarry Hendrikse More articles by this author , Ronald BoellaardRonald Boellaard More articles by this author , Daniela Oprea-LagerDaniela Oprea-Lager More articles by this author , and André VisAndré Vis More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002023.04AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Prostate cancer (PCa) staging has been improved by prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PSMA-PET/CT). Intraprostatic PSMA intensity, as measured by standardized uptake values (SUV), could predict clinically relevant oncological outcomes for PCa. This study aims to investigate the correlation between SUV in patients with PCa prior to radical prostatectomy (RP) and adverse pathology outcomes, including Gleason score (GS), pN1 status and biochemical progression-free survival (PFS). METHODS: A total of 318 patients with biopsy-proven PCa scheduled for RP with a pelvic lymph node dissection in 84.5%, (269/318 patients) were retrospectively analysed (median PSA: 10.5 ng/ml). Prior to RP, patients received a PET/CT with either 68Ga-PSMA (189/318 (59%) patients) or 18F-DCFPyL-PSMA (129/318 (41%) patients). PET/CT images were analysed visually and semi-quantitatively by measuring the maximum SUV (SUVmax) of the most intense suspect lesion in the prostate. The SUVmax of the primary tumour was assessed in relation to GS, pN1 status and PFS. RESULTS: Patients with PCa tumours with a GS of ≤7 showed significantly lower SUVmax compared to patients with GS >7 for both tracers (SUVmax F18: 7.4 versus 14.5; p<0.001, SUVmax Ga68: 7.3 versus 9.3; p=0.01). Moreover, PCa patients with positive lymph nodes on pathology examination exhibited significantly higher median uptake than those without for both tracers (SUVmax F18: 7.9 versus 12.3; p=0.04, SUVmax Ga68: 7.6 versus 12.0 p<0.001). Of the total cohort, 77.6% (247/318) of patients were free from progression at a median follow-up of 11.6 months (Range 1.4–32.8 months). As shown in figure 1, the pooled lower quartiles of SUVmax for both tracers showed a favourable PFS versus the upper 2 quartiles (p<0.001). CONCLUSIONS: Intraprostatic PSMA-PET/CT intensity, as measured by SUVmax is prognostic and may be a valuable new biomarker in localised PCa. The GS, pN1 status and PFS correlated with the intensity of tracer accumulation in the primary tumours of PC patients on PSMA PET/CT with both the 68Ga-PSMA and 18F-DCFPyL-PSMA tracers. Source of Funding: n/a © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e463-e463 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Yves Bodar More articles by this author Hans Veerman More articles by this author Katelijne de Bie More articles by this author Dennie Meijer More articles by this author Pim van Leeuwen More articles by this author Maarten Donswijk More articles by this author Harry Hendrikse More articles by this author Ronald Boellaard More articles by this author Daniela Oprea-Lager More articles by this author André Vis More articles by this author Expand All Advertisement Loading ...

Interdisciplinary expert consensus on innovations in imaging diagnostics and radionuclide-based therapies for advanced prostate cancer

HintergrundDie zahlreichen diagnostischen und therapeutischen Innovationen beim fortgeschrittenen Prostatakarzinom, sowohl in der hormonsensitiven als auch in der kastrationsresistenten Situation, haben in den letzten Jahren zu einer Neuorientierung beim Management dieses Tumors geführt. Ungeachtet der bereits in Teilen in der S3-Leitlinie zu Früherkennung, Diagnose und Therapie des Prostatakarzinoms abgebildeten neuen diagnostischen und therapeutischen Methoden, gibt es in der klinischen Versorgung darüber hinaus gehende Fälle, in denen Patienten von diesen innovativen Verfahren potenziell profitieren könnten.FragestellungSeit Juli 2018 trifft sich deshalb eine interdisziplinäre Expertengruppe aus Nuklearmedizinern, Radiologen, Radioonkologen und Urologen, um ein Konsensuspapier zu Innovationen der bildgebenden Diagnostik und radionuklidbasierten Therapien des fortgeschrittenen Prostatakarzinoms vor dem Hintergrund aktueller Studien und Erfahrungen im klinischen Alltag zu erarbeiten.SchlussfolgerungDer Arbeitskreis gibt Anregungen, um zu einer besseren Implementierung neuer bildgebender Techniken, wie multiparametrische Magnetresonanztomographie (mpMRT), PSMA-PET/CT (prostataspezifisches Membranantigen – Positronenemissionstomographie/Computertomographie) und innovativer therapeutischer Optionen (Radium-223-dichlorid, Lutetium-177-PSMA) bei den komplexen Therapieoptionen des fortgeschrittenen Prostatakarzinoms beizutragen.

Clinical aspects in the diagnosis and treatment of prostate cancer

Diagnosis and treatment of primary prostate cancer (PCA) have undergone significant changes in the last few years due to modern imaging. Established and modern diagnostic and therapeutic modalities for detection and treatment of primary PCA are presented and discussed critically. Background knowledge and guideline recommendations on primary PCA are summarized and additional information from relevant publications is given. Modern imaging, in particular multiparametric magnetic resonance imaging (mpMRI), has revolutionized the diagnostic work-up of primary PCA. Due to mpMRI, tumors are detected significantly better in both initial and re-biopsy with asignificant reduction of overdiagnosis of clinically insignificant PCA. Therapeutic approaches such as active surveillance, radical prostatectomy and focal therapies are increasingly being planned and carried out relying on MR-imaging information concerning tumor extent and tumor aggressiveness. In addition, prostate-specific membrane antigen-positron emission tomography/computed tomography (PSMA-PET/CT) has shown superiority in assessing patients with suspected biochemical recurrence and in primary staging of PCA compared to conventional imaging in terms of detection of metastases. Modern imaging, especially mpMRI and PSMA-PET/CT, has added substantial benefits in modern diagnosis and treatment of primary PCA. Moreover, multiparametric ultrasound is also apromising addition to the radiological armamentarium in the management of primary PCA.

Estimating the Potential of Radiomics Features and Radiomics Signature from Pretherapeutic PSMA-PET-CT Scans and Clinical Data for Prediction of Overall Survival When Treated with 177Lu-PSMA.

Prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PSMA-PET/CT) scans can facilitate diagnosis and treatment of prostate disease. Radiomics signature (RS) is widely used for the analysis of overall survival (OS) in cancer diseases. This study aims at investigating the role of radiomics features (RFs) and RS from pretherapeutic gallium-68 (68Ga)-PSMA-PET/CT findings and patient-specific clinical parameters to analyze overall survival of prostate cancer (PC) patients when treated with lutethium-177 (177Lu)-PSMA. A cohort of 83 patients with advanced PC was retrospectively analyzed. Average values of 73 RFs of 2070 malignant hotspots as well as 22 clinical parameters were analyzed for each patient. From the Cox proportional hazard model, the least absolute shrinkage and selection operator (LASSO) regularization method is used to select most relevant features (standardized uptake value (SUV)Min and kurtosis with the coefficients of 0.984 and −0.118, respectively) and to calculate the RS from the RFs. Kaplan–Meier (KM) estimator was used to analyze the potential of RFs and conventional clinical parameters, such as metabolic tumor volume (MTV) and standardized uptake value (SUV) for the prediction of survival. As a result, SUVMin, kurtosis, the calculated RS, SUVMean, as well as Hemoglobin (Hb)1, C-reactive protein (CRP)1, and ECOG1 (clinical parameters) achieved p-values less than 0.05, which suggest the potential of findings from 68Ga-PSMA-PET/CT scans as well as patient-specific clinical parameters for the prediction of OS for patients with advanced PC treated with 177Lu-PSMA therapy.

68Ga-PSMA-PET/CT-based radiosurgery and stereotactic body radiotherapy for oligometastatic prostate cancer.

Androgen deprivation therapy (ADT) remains the standard therapy for patients with oligometastatic prostate cancer (OMPC). Prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA-PET/CT)-based stereotactic body radiotherapy (SBRT) is emerging as an alternative option to postpone starting ADT and its associated side effects including the development of drug resistance. The aim of this study was to determine progression free-survival (PFS) and treatment failure free-survival (TFFS) after PSMA-PET/CT-based SBRT in OMPC patients. The efficacy and safety of single fraction radiosurgery (SFRS) and ADT delay were investigated. Patients with ≤5 metastases from OMPC, with/without ADT treated with PSMA-PET/CT-based SBRT were retrospectively analyzed. PFS and TFFS were primary endpoints. Secondary endpoints were local control (LC), overall survival (OS) and ADT-free survival (ADTFS). Fifty patients with a total of 75 metastases detected by PSMA-PET/CT were analyzed. At the time of SBRT, 70% of patients were castration-sensitive. Overall, 80% of metastases were treated with SFRS (median dose 20 Gy, range: 16-25). After median follow-up of 34 months (range: 5-70) median PFS and TFFS were 12 months (range: 2-63) and 14 months (range: 2-70), respectively. Thirty-two (64%) patients had repeat oligometastatic disease. Twenty-four (48%) patients with progression underwent second SBRT course. Two-year LC after SFRS was 96%. Grade 1 and 2 toxicity occurred in 3 (6%) and 1 (2%) patients, respectively. ADTFS and OS rates at 2-years were 60.5% and 100%, respectively. In multivariate analysis, TFFS significantly improved in patients with time to first metastasis (TTM) >36 months (p = 0.01) and PSA before SBRT ≤1 ng/ml (p = 0.03). For patients with OMPC, SBRT might be used as an alternative to ADT. This way, the start/escalation of palliative ADT and its side effects can be deferred. Metastases treated with PSMA-PET/CT-based SFRS reached excellent LC with minimal toxicity. Low PSA levels and longer TTM predict elongated TFFS.

Dedicated Verification of an Accessory Parotid Gland via Minimal-Activity PSMA-PET/CT.

Gallium-68-labeled prostate-specific membrane antigen ligands are not only established radiopharmaceuticals for staging of prostate cancer but also accumulate physiologically in nonprostate organs, including the salivary glands. We show the converted application of prostate-specific membrane antigen -positron emission tomography/computed tomography (PSMA-PET/CT) as a dedicated method to depict salivary gland tissue using a region-focused, low-dose protocol. An accessory parotid gland at the right buccal region could be confirmed; therefore, further diagnostic or invasive therapeutic steps were not necessary.

Correlations of the 68Ga-PSMA PET/CT derived primary prostate tumor PSMA expression parameters and metastatic patterns in patients with Gleason Score >7 prostate cancer.

We aimed to investigate the correlations between the prostate specific membrane antigen (PSMA) expression parameters of the primary prostate tumor on gallium-68 (68Ga)-PSMA positron emission tomography/computed tomography (PET/CT) with metastatic patterns in patients with Gleason Score (GS) >7 prostate cancer (PCa). This study included 55 PCa patients who had 68Ga-PSMA PET/CT performed for staging. According to metastatic pattern, patients were divided into 3 groups as non-metastatic (N0M0), those with isolated pelvic lymph node metastasis (N1M0) and with distant metastasis (M1). The correlations between the primary tumor PSMA expression parameters such as maximum standardize uptake value (SUVmax), SUVmean, PSMA-TV (PSMA receptor expressing tumour volume), and TL-PSMA (total lesion PSMA receptor expression) on 68Ga-PSMA PET/CT imaging and metastatic patterns were investigated. There were 21, 9 and 25 patients in the N0M0, N1M0 and M1 groups, respectively. The PSMA-TV and TL-PSMA values were significantly higher in the N1M0 and the M1 patient groups compared to the N0M0 group, but there was no significant difference between the N1M0 and M1 groups. The primary tumor SUVmax and SUVmean values were not significantly different between the three groups. The optimal PSMA-TV cut-off value for metastasis was >8.07cm3 (AUC 0.86) with sensitivity of 76.5% and specificity 85.7%. The optimal TL-PSMA cut-off value for metastasis was >93 (AUC 0.74) with sensitivity of 64%, and specificity 100%. The PSMA-TV and TL-PSMA values are strong markers for metastasis prediction in patients with GS >7 PCa but no other PSMA expression parameters can distinguish between N1M0 and M1 groups.