68Ga-PSMA-11 PET/CT for prostate cancer staging and risk stratification in Chinese patients

Should new organ involvement be included in Response Evaluation Criteria in PSMA Imaging?

PURPOSE

The current study is intended to investigate the effect of new organ involvement on overall survival (OS) and modify the Response Evaluation Criteria in PSMA Imaging (RECIP) by including new organ involvement to RECIP 1.0.

MATERIALS AND METHODS

This retrospective study includes 114 patients diagnosed with metastatic castration-resistant prostate cancer (mCRPC) between September 2017 and June 2022 who had received docetaxel treatment and had baseline and post-treatment prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) images. The inclusion criteria were patients with pre- and post-treatment [18F]FDG PET/CT images and whose [18F]FDG PET images were negative. Those whose data were unavailable, who had additional malignancy, or who received abiraterone, enzalutamide, or Lutetium (Lu)-177 treatment were excluded. Age, Gleason score (GS), TPSA (total prostate-specific antigen) levels, surgical history, and OS information were recorded for each patient.

RESULTS

The 114 patients herein had a median age of 72.5 (51-91) years and a median GS of 8 (7-10). New lesions were observed in 59 patients (51.7%) and new organ PSMA uptake was observed in 14 patients (12.2%). In the multivariate Cox regression analysis, volume-based treatment response (vTR)-total lesion PSMA (TLP), RECIP PSMA-VOL, modified RECIP (mRECIP) PSMA-VOL, and mRECIP TLP were independent prognostic factors for mortality (p < 0.001, p = 0.006, p = 0.003, and p = 0.003, respectively). The median OS of patients with new organ involvement and new lesion with PSMA uptake was 9.3 months (95% CI 2.1-16.5 months) and 11.8 months (95% CI 7.4-16.2 months), respectively.

CONCLUSION

The study concluded that new organ involvement had a shorter OS than new lesion involvement. In the mRECIP that we developed, unlike RECIP, we demonstrated that both PSMA-VOL and TLP value were independent prognostic factors for mortality.

PSMA PET/CT in Castration-Resistant Prostate Cancer: Myth or Reality?

BACKGROUND

prostate-specific membrane antigen (PSMA) ligand PET has been recently incorporated into international guidelines for several different indications in prostate cancer (PCa) patients. However, there are still some open questions regarding the role of PSMA ligand PET in castration-resistant prostate cancer (CRPC). The aim of this work is to assess the clinical value of PSMA ligand PET/CT in patients with CRPC.

RESULTS

PSMA ligand PET has demonstrated higher detection rates in comparison to conventional imaging and allows for a significant reduction in the number of M0 CRPC patients. However, its real impact on patients' prognosis is still an open question. Moreover, in CRPC patients, PSMA ligand PET presents some sensitivity and specificity limitations. Due to its heterogeneity, CRPC may present a mosaic of neoplastic clones, some of which could be PSMA-/FDG+, or vice versa. Likewise, unspecific bone uptake (UBU) and second primary neoplasms (SNPs) overexpressing PSMA in the neoangiogenic vessels represent potential specificity issues. Integrated multi-tracer imaging (PSMA ligand and [18F]FDG PET) together with a multidisciplinary discussion could allow for reaching the most accurate evaluation of each patient from a precision medicine point of view.

PSMA PET/CT: joint EANM procedure guideline/SNMMI procedure standard for prostate cancer imaging 2.0

Here we aim to provide updated guidance and standards for the indication, acquisition, and interpretation of PSMA PET/CT for prostate cancer imaging. Procedures and characteristics are reported for a variety of available PSMA small radioligands. Different scenarios for the clinical use of PSMA-ligand PET/CT are discussed. This document provides clinicians and technicians with the best available evidence, to support the implementation of PSMA PET/CT imaging in research and routine practice.

177Lu-PSMA-I&T Radioligand Therapy for Treating Metastatic Castration-Resistant Prostate Cancer: A Single-Centre Study in East Asians

Purpose

There is increasing evidence for convincing efficacy and safety of ¹⁷⁷Lu-labled prostate-specific membrane antigen (PSMA)-targeted radioligand therapy (PRLT) for metastatic castration-resistant prostate cancer (mCRPC). However, data are not available regarding the feasibility of ¹⁷⁷Lu-labled PSMA-targeted RLT in East Asians. The present study summarized the first experience with ¹⁷⁷Lu-PSMA-I&T therapy for mCRPC in China.

Methods

Forty consecutive patients with mCRPC were enrolled from December 2019 to September 2021. Eligible patients received ¹⁷⁷Lu-PSMA-I&T RLT at intervals of 8-12 weeks. Toxicity was assessed based on standardized physicians’ reports and the Common Toxicity Criteria for Adverse Events criteria. Response to PRLT was evaluated according to the changes of prostate specific antigen (PSA) response and imaging response. Quality of life (QOL), Karnofsky performance status (KPS) and pain (visual analogue scale, VAS) were also evaluated. The impacts of baseline parameters on the therapeutic effects were explored by univariate and multivariate logistic regression analyses.

Results

All patients underwent a total of 86 cycles of ¹⁷⁷Lu-PSMA-I&T (range: 1-5 cycles) with dosages of 3.70-14.43GBq per cycle, with a median of 8 months followed up. Six patients (15%) developed mild reversible xerostomia during follow-up, and 28 patients (70%) experienced grade 1-4 bone marrow dysfunction. Changes in PSA were assessed after therapy, accompanied by the partial response (PR) in 25 patients (62.5%), the stable disease (SD) in 5 patients (12.5%), and the progressive disease (PD) in 10 patients (25%), respectively. QOL, KPS (%) and VAS scores were improved significantly due to treatment (P<0.05). Overweight and elevated AST, ALP, and LDH were associated with poor outcomes.

Conclusions

¹⁷⁷Lu-PSMA-I&T achieves the favourable response and well tolerance in mCRPC, which associates with not only PSA decline but also with tumor remission including lymphadenopathy and bone metastasis. We also find that patients with overweight and high AST, ALP, and LDH should be cautious to undergo the PRLT. Large-cohort studies are warranted to confirm the initial findings and elucidate the survival benefit of the treatment.

Pelvic lymph node dissection in high-risk prostate cancer

INTRODUCTION

The therapeutic role of pelvic lymph node dissection (PLND) in prostate cancer (PCa) is unknown due to absence of randomized trials.

OBJECTIVE

to present a critical review on the therapeutic benefits of PLND in high risk localized PCa patients.

MATERIALS AND METHODS

A search of the literature on PLND was performed using PubMed, Cochrane, and Medline database. Articles obtained regarding diagnostic imaging and sentinel lymph node dissection, PLND extension, impact of PLND on survival, PLND in node positive "only" disease and PLND surgical risks were critically reviewed.

RESULTS

High-risk PCa commonly develops metastases. In these patients, the possibility of presenting lymph node disease is high. Thus, extended PLND during radical prostatectomy may be recommended in selected patients with localized high-risk PCa for both accurate staging and therapeutic intent. Although recent advances in detecting patients with lymph node involvement (LNI) with novel imaging and sentinel node dissection, extended PLND continues to be the most accurate method to stage lymph node disease, which may be related to the number of nodes removed. However, extended PLND increases surgical time, with potential impact on perioperative complications, hospital length of stay, rehospitalization and healthcare costs. Controversy persists on its therapeutic benefit, particularly in patients with high node burden.

CONCLUSION

The impact of PLND on biochemical recurrence and PCa survival is unclear yet. Selection of patients may benefit from extended PLND but the challenge remains to identify them accurately. Only prospective randomized study would answer the precise role of PLND in high-risk pelvis confined PCa patients.

Molecular Imaging in Primary Staging of Prostate Cancer Patients: Current Aspects and Future Trends

Accurate primary staging is the cornerstone in all malignancies. Different morphological imaging modalities are employed in the evaluation of prostate cancer (PCa). Regardless of all developments in imaging, invasive histopathologic evaluation is still the standard method for the detection and staging of the primary PCa. Magnetic resonance imaging (MRI) and computed tomography (CT) play crucial roles; however, functional imaging provides additional valuable information, and it is gaining ever-growing acceptance in the management of PCa. Targeted imaging with different radiotracers has remarkably evolved in the past two decades. [111In]In-capromab pendetide scintigraphy was a new approach in the management of PCa. Afterwards, positron emission tomography (PET) tracers such as [11C/18F]choline and [11C]acetate were developed. Nevertheless, none found a role in the primary staging. By introduction of the highly sensitive small molecule prostate-specific membrane antigen (PSMA) PET/CT, as well as recent developments in MRI and hybrid PET/MRI systems, non-invasive staging of PCa is being contemplated. Several studies investigated the role of these sophisticated modalities in the primary staging of PCa, showing promising results. Here, we recapitulate the role of targeted functional imaging. We briefly mention the most popular radiotracers, their diagnostic accuracy in the primary staging of PCa, and impact on patient management.

Relationship between serum lipid levels and ischemic stroke in patients with atrial fibrillation: a nested case-control study based on the China Atrial Fibrillation Registry

BACKGROUND

Atrial fibrillation (AF) is an important risk factor for acute ischemic stroke.

METHODS

A nested case-control study was conducted among patients diagnosed with AF, whose information was acquired from the prospective China Atrial Fibrillation Registry (China-AF), from August 2011 to December 2018.

RESULTS

This study compared patients with stroke group (n = 145) with a matched control group (n = 577). Demographic data were similar except for body mass index (BMI), diastolic blood pressure (DBP) which were higher, and new oral anticoagulant (NOAC) treatment rate which was lower in the stroke group (all P < 0.05). Baseline median [IQR] levels of including triglyceride (TG) were higher in the stroke group (21.96 [16.74, 21.52], mg/dL) than the control group (19.62 [14.76, 27.36], mg/dL) (P = 0.012), while the total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) were similar between the two groups. Elevated TG and HDL-C were positively associated with ischemic stroke (OR 1.01, 95% CI 1.00-1.02, P = 0.032; OR 1.03, 95% CI 1.00-1.05, P = 0.025), after adjustment for BMI, systolic blood pressure, DBP, CHA₂DS₂-VASc score, HAS-BLED score, NOAC, LDL-C and HDL-C. However, NOAC (OR 0.20, 95% CI 0.05-0.84, P = 0.029) could decrease the likelihood of ischemic stroke in patients with AF. In subgroup analysis, higher TG level remained significantly associated with ischemic stroke for AF patients without a history of smoking (OR 1.26, 95% CI 1.02-1.55, P = 0.028).

CONCLUSION

Higher level of TG and HDL-C were positively associated with ischemic stroke in patients with AF.

Radiomics, Radiogenomics, and Next-Generation Molecular Imaging to Augment Diagnosis of Hepatocellular Carcinoma

Ultrasound, computed tomography, magnetic resonance imaging, and [F]F-fluorodeoxyglucose positron emission tomography are invaluable in the clinical evaluation of human cancers. Radiomics and radiogenomics tools may allow clinicians to standardize interpretation of these conventional imaging modalities, while better linking radiographic hallmarks to disease biology and prognosis. These advances, coupled with next-generation positron emission tomography imaging tracers capable of providing biologically relevant tumor information, may further expand the tools available in our armamentarium against human cancers. We present current imaging methods and explore emerging research that may improve diagnosis and monitoring of local, oligometastatic, and disseminated cancers exhibiting heterogeneous uptake of [F]F-fluorodeoxyglucose, using hepatocellular carcinoma as an example.

68Ga-Prostate-specific membrane antigen (psma) positron emission tomography (pet) in prostate cancer: a systematic review and meta-analysis

Introduction:

Prostate cancer (PC) is the second most commonly diagnosed cancer in males. ⁶⁸Ga-PSMA PET/CT, a non-invasive diagnostic tool to evaluate PC with prostate-specific membrane antigen (PSMA) expression, has emerged as a more accurate alternative to assess disease staging. We aimed to identify predictors of positive ⁶⁸Ga-PSMA PET and the accuracy of this technique.

Materials and methods:

Diagnostic accuracy cross-sectional study with prospective and retrospective approaches. We performed a comprehensive literature search on PubMed, Cochrane Library, and Embase database in search of studies including PC patients submitted to radical prostatectomy or radiotherapy with curative intent and presented biochemical recurrence following ASTRO 1996 criteria. A total of 35 studies involving 3910 patients submitted to 68-Ga-PSMA PET were included and independently assessed by two authors: 8 studies on diagnosis, four on staging, and 23 studies on restaging purposes. The significance level was α=0.05.

Results:

pooled sensitivity and specificity were 0.90 (0.86-0.93) and 0.90 (0.82-0.96), respectively, for diagnostic purposes; as for staging, pooled sensitivity and specificity were 0.93 (0.86-0.98) and 0.96 (0.92-0.99), respectively. In the restaging scenario, pooled sensitivity and specificity were 0.76 (0.74-0.78) and 0.45 (0.27-0.58), respectively, considering the identification of prostate cancer in each described situation. We also obtained specificity and sensitivity results for PSA subdivisions.

Conclusion:

⁶⁸Ga-PSMA PET provides higher sensitivity and specificity than traditional imaging for prostate cancer.

PSMA whole-body tumor burden in primary staging and biochemical recurrence of prostate cancer

PURPOSE

The objective of this study was to evaluate whether ⁶⁸Ga-PSMA PET/CT whole-body tumor burden (PSMAwbtb) is associated with clinical parameters and laboratory parameters in prostate cancer patients.

METHODS

We retrospectively evaluated prostate cancer patients submitted to PSMA PET/CT for primary staging purposes or due to biochemical recurrence (BR). PSMAwbtb metrics (total volume of PSMA-avid tumor (PSMA-TV)) and total uptake of PSMA-avid lesions (PSMA-TL) were calculated semi-automatically. Spearman's rank correlations between PSMAwbtb metrics and clinical, laboratory parameters (age, time-to-BR, years of diagnosis of prostate cancer, free and total serum PSA levels, and the Gleason score) and with the highest SUVmax of a lesion (hSUVmax) were analyzed.

RESULTS

Among the 257 PSMA PET/CT studies, there were 46 scans (17.9%) performed for primary staging and 211 (82.1%) for BR. PSMA-TV and PSMA-TL were calculated for the 157 positive scans (58.8%), which were 43 patients (93.5%) in the primary staging group and 114 patients (54.0%) in the BR group. In the primary staging group, we observed a significant correlation between PSMA-TL and hSUVmax (p = 0.0021). In the BR group, there was a significant direct correlation between PSMA-TL and the variables age (p = 0.0031), total serum PSA values (p = < 0.0001), free serum PSA values (p = < 0.0001), and the hSUVmax (p = < 0.0001). Similar results were obtained for PSMA-TV.

CONCLUSION

PSMAwbtb has a direct and positive correlation with serum PSA values and age in prostate cancer patients with BR.

Prostate-specific Membrane Antigen-based Imaging of Castration-resistant Prostate Cancer

CONTEXT

Positron emission tomography (PET) targeting prostate-specific membrane antigen (PSMA) has unprecedented accuracy for localization of initial or recurrent prostate cancer (PC). There is now growing evidence regarding the value of PSMA-PET in patients with advanced PC.

OBJECTIVE

To review the value of PSMA-PET/computed tomography (CT) in the context of castration-resistant PC (CRPC).

EVIDENCE ACQUISITION

A search of the PubMed database using the terms "PSMA PET castration resistant prostate cancer" (years 2011-2020) was performed. Reviews, case reports/series, non-English articles, preclinical studies, access-restricted studies, and studies on PSMA radioligand therapy without further analysis of PSMA-PET parameters were subsequently excluded.

EVIDENCE SYNTHESIS

Compared to conventional imaging, PSMA-PET better identifies the true extent of CRPC, especially nonmetastatic CRPC. The clinical benefit of this stage migration is still unclear and needs to be evaluated in further studies. High accuracy of PSMA-PET holds promise for better, PET-guided metastasis-directed treatment in patients with oligometastatic CRPC. PSMA-PET is an essential eligibility criterion for [¹⁷⁷Lu]-PSMA theranostic applications. Preliminary evidence indicates the value of PSMA-PET for the assessment of treatment responses.

CONCLUSIONS

Among other applications, PSMA-PET offers more precise staging for nonmetastatic CRPC. In particular, target localization for metastasis-directed therapy and target expression assessment for PSMA radioligand therapy also hold promise. Potential translation of this diagnostic tool into an oncologic benefit needs to be defined in future trials.

PATIENT SUMMARY

This review describes how prostate-specific membrane antigen positron emission tomography (PSMA-PET), a new sensitive imaging tool for prostate cancer, might help to guide clinicians in making treatment decisions for advanced prostate cancer.

68Ga-PSMA-11 PET/CT combining ADC value of MRI in the diagnosis of naive prostate cancer: Perspective of radiologist

Ga-PSMA-11 positron emission computed tomography /computed tomography (PET/CT) is more sensitive than magnetic resonance imaging (MRI) in detecting prostate cancer (PCa). We evaluated the value of Ga-PSMA-11 PET/CT with MRI in treatment-naive PCa.This retrospective study was approved by the hospital ethics committee. The MRI and Ga-PSMA-11 PET/CT imaging data of 63 cases of highly suspected PCa were enrolled in this study. The SUVmax and apparent diffusion coefficient (ADC), and their ratio, were assessed as diagnostic markers to distinguish PCa from benign disease.There were 107 prostate lesions detected in 63 cases. Forty cases with 64 malignant primary lesions were confirmed PCa, whereas 23 cases had 43 benign lesions. PSMA-avid lesions correlated with hypointense signal on ADC maps and hyperintense signal on diffusion-weighted imaging. The ADC of PCa was lower than that of benign lesions, and SUVmax and SUVmax/ADC of PCa was higher than that of benign lesions (P < .01). ADC had significant negative correlation with Gleason score (GS) and SUVmax, SUVmax, and SUVmax/ADC positively correlated with GS. From ROC analysis, we established cutoff values of ADC, SUVmax, and SUVmax/ADC at 1.02 × 10mm/s, 11.72, and 12.35, respectively, to differentiate PCa from benign lesions. The sensitivity, specificity, and AUC were 90.6%, 58.1%, and 0.816 for ADC, 67.2%, 97.7%, and 0.905 for SUVmax, and 81.2%, 88.4%, and 0.929 for SUVmax/ADC, respectively.Ga-PSMA-11 PET/CT combined with MRI offers higher diagnostic efficacy in the detection of PCa than either modality alone.

68Ga-PSMA PET/CT targeted biopsy for the diagnosis of clinically significant prostate cancer compared with transrectal ultrasound guided biopsy: a prospective randomized single-centre study

Purpose

⁶⁸Ga-prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) is valuable for detecting primary and recurrent prostatic lesions. This study aimed to evaluate the efficacy of ⁶⁸Ga-PSMA-11 PET/CT as a triage tool for prostate biopsy (PSMA-TB) and compare with transrectal ultrasound-guided biopsy (TRUS-GB) for the diagnosis of clinically significant prostate cancer (csPCa).

Methods

This single-centre study randomly allocated 120 patients with elevated serum prostate-specific antigen (PSA) levels (> 4 ng/ml) to PSMA-PET or TRUS group. Patients with PSMA-avid lesions (SUVmax ≥ 8.0) underwent PSMA-TB via a single-puncture percutaneous transgluteal approach (n = 25), whilst patients with negative PSMA-PET underwent systematic TRUS-GB (n = 35). All patients in the TRUS group underwent TRUS-GB directly (n = 60).

Results

PCa and csPCa were detected in 26/60 (43.3%) and 24/60 (40.0%) patients in the PSMA-PET group and 19/60 (31.6%) and 15/60 (25.0%) in the TRUS group, respectively. In the PSMA-PET group, the detection rate of PCa and csPCa were significantly higher in PSMA-PET-positive than negative patients (PCa, 23/25 (92.0%) vs 3/35 (8.6%), P < 0.01; csPCa, 22/25 (88.0%) vs 2/35 (5.7%), P < 0.01). PSMA-TB detected significantly more PCa and csPCa than TRUS-GB in the TRUS controls (PCa, 21/25 (84.0%) vs 19/60 (31.6%), P < 0.01; csPCa, 20/25 (80.0%) vs 15/60 (25.0%), P < 0.01). PSMA-PET detected significantly more cases of csPCa amongst patients with PSA 4.0–20.0 ng/ml than TRUS (27.02% vs 8.82%, P < 0.05). No haematuria, urinary retention or pelvic infection was observed after PSMA-TB compare with TRUS-GB.

Conclusions

⁶⁸Ga-PSMA-11 PET/CT is a feasible imaging technique that may serve as a triage tool for prostate biopsy, and may improve the detection rate of csPCa compared with TRUS-GB, especially in patients with serum PSA 4.0–20.0 ng/ml.

Comparison of 68Ga-PSMA-617 PET/CT with mpMRI for the detection of PCa in patients with a PSA level of 4-20 ng/ml before the initial biopsy

The study was aimed at assessing the diagnostic performance of ⁶⁸Ga-PSMA-617 PET/CT in the detection of prostate cancer (PCa) in patients with a prostate-specific antigen (PSA) level of 4–20 ng/ml and to compare its efficacy with that of multiparametric MRI (mpMRI). We analyzed the data of 67 consecutive patients with PSA levels of 4–20 ng/ml who almost simultaneously underwent ⁶⁸Ga-PSMA-617 PET/CT and mpMRI. ⁶⁸Ga-PSMA-617 PET/CT and mpMRI diagnostic performances were compared via receiver operating characteristic (ROC) curve analysis. Of the 67 suspected PCa cases, 33 had pathologically confirmed PCa. ⁶⁸Ga-PSMA-617 PET/CT showed a patient-based sensitivity, specificity, and positive and negative predictive values (PPVs and NPVs) of 87.88%, 88.24%, 87.88%, and 88.24%, respectively. The corresponding values for mpMRI were 84.85%, 52.94%, 63.64%, and 78.26%. The area under the curve values for ⁶⁸Ga-PSMA-617 PET/CT and mpMRI were 0.881 and 0.689, respectively. ⁶⁸Ga-PSMA-617 PET/CT showed a better diagnostic performance than mpMRI in the detection of PCa in patients with PSA levels of 4–20 ng/ml.

Current and potential future role of PSMA-PET in patients with castration-resistant prostate cancer

PURPOSE

To review the current literature and discuss potential future roles of the novel positron emission tomography (PET) tracers targeting the prostate-specific membrane antigen (PSMA) in patients with castration-resistant prostate cancer (CRPC).

METHODS

A literature search on February 19th 2018 was conducted using the Medline database and www.clinicaltrials.gov . Additionally, illustrative cases of CRPC patients from our own institution who were restaged and treated based on PSMA-PET scan results are provided.

RESULTS

11 Studies met the inclusion criteria. PSMA-PET detected more metastatic lesions compared to conventional bone scan. Several patients were up-staged from non-metastatic CRPC (nmCRPC) to metastatic CRPC (mCRPC). Currently, no clear consensus exists regarding treatment response assessment in PSMA-PET scans for mCRPC patients undergoing treatment. Also, the role of PSMA-PET as a gatekeeper for systemic therapy or radioligands is currently undefined. PSMA-guided metastasis-directed radiotherapy may not only alleviate local symptoms but has the potential to defer systemic treatment in patients with oligoprogressive CRPC.

CONCLUSION

Compared to bone scan, PSMA-PET is more sensitive and specific to detect metastases but the therapeutic consequences of PSMA-PET results in the setting of CRPC remain unclear. Until future studies define the role of PSMA-PET in patients with CRPC, the current standard for imaging remains bone scan and computerized tomography.

Initial risk stratification and staging in prostate cancer with prostatic-specific membrane antigen positron emission tomography/computed tomography: A first-stop-shop

Current imaging for prostate cancer (PCa) had limitations for risk stratification and staging. Magnetic resonance imaging frequently underestimated lymph node metastasis while bone scintigraphy often had diagnostic dilemmas. Prostatic-specific membrane antigen (PSMA) positron emission tomography-computed tomography (PET/CT) has been remarkable in PCa recurrence. Ninety-seven PSMA PET-CT scans were reanalyzed for tumor node metastases staging and risk stratification of lymph node and distant metastasis proportion. Histopathology of 23/97 patients was available as gold standard. Chi-square test was used for proportion comparison. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), overestimation, underestimation, and correct estimation of T and N stages were calculated. Kappa coefficient (κ) was derived for inter-rater agreement. Lymph node or distant metastasis detection on PSMA PET/CT increased significantly with increase in risk category. PSMA PET/CT sensitivity, specificity, PPV, and NPV for extraprostatic extension, seminal vesicle invasion, and lymph node metastases were 63.16%, 100%, 100%, 36.36%; 55%, 100%, 100%, 25%; and 65.62%, 99.31%, 87.50%, and 97.53%, respectively. Kappa coefficient showed substantial agreement between PSMA PET/CT and histopathological lymph node metastases (κ = 0.734); however, it was just in fair agreement (κ = 0.277) with T stage. PSMA PET/CT overestimated, underestimated, and correct estimated T and N stages in 8.71%, 39.13%, 52.17% and 8.71%, 4.35%, and 86.96% cases, respectively. PSMA PET/CT has potential for initial risk stratification with reasonable correct N stage estimation, however underestimates T stage. Hence, we concluded that PSMA PET/CT should be used as “ first-stop-shop” for staging and initial risk stratification of PCa with regional magnetic resonance imaging in surgically resectable cases.

Comparison of 68Ga-PSMA-11 PET-CT with mpMRI for preoperative lymph node staging in patients with intermediate to high-risk prostate cancer

Background

To evaluate the diagnostic value of ⁶⁸Ga-PSMA-11 PET-CT with multiparametric magnetic resonance imaging (mpMRI) for lymph node (LN) staging in patients with intermediate- to high-risk prostate cancer (PCa) undergoing radical prostatectomy (RP) with pelvic lymph node dissection (PLND).

Methods

We retrospectively identified 42 consecutive patients with intermediate- to high-risk PCa according to D′Amico and without concomitant cancer. Preoperative ⁶⁸Ga-PSMA-11 PET-CT, pelvic mpMRI and subsequent robot assisted laparoscopic RP with PLND were performed in all patients.

Results

Among 42 patients assessed, the preoperative PSA value, Gleason score, pT stage and intraprostatic PCa volume of patients with LN metastases were all significantly higher than those without metastases (P = 0.029, 0.028, 0.004, respectively). The average maximum standardized uptake value (SUV) of ⁶⁸Ga-PSMA-11 PET-CT positive PCa of patients with or without LN metastases were 13.10 (range 6.12–51.75) and 7.22 (range 5.4–11.2), respectively (P < 0.001). ⁶⁸Ga-PSMA-11 PET-CT and pelvic mpMRI had the ability of succeed on preoperative definite accurate diagnosis and accurate localization of primary PCa in all 42 patients. Fifteen patients (35.71%) had a pN1 stage. 51 positive LN were found. Both ⁶⁸Ga-PSMA-11 PET-CT and pelvic mpMRI displayed brillient patient-based and region-based sensitivity, specificity, negative predictive value and positive predictive value. There was no statistical difference for the detection of LNMs according to the diameter of the LNMs between ⁶⁸Ga-PSMA-11 PET-CT and mpMRI in this study.

Conclusions

Both ⁶⁸Ga-PSMA-11 PET-CT and mpMRI performed great value for LN staging in patients with intermediate- to high-risk PCa undergoing RP with PLND. However, despite excellent performance of ⁶⁸Ga-PSMA-11 PET-CT, it cannot replace mpMRI that remains excellent for lymph node staging.