Dataset Information

Assessment of Bone Metastases in Patients with Prostate Cancer-A Comparison between ^99mTc-Bone-Scintigraphy and [⁶⁸Ga]Ga-PSMA PET/CT.

ABSTRACT:

Purpose

Bone scintigraphy is the standard of reference in bone metastases in prostate cancer patients. However, new radiotracers employed in prostate-specific membrane antigen (PSMA)-ligands has led to the growing importance of PET/CT as diagnostic tool. The aim of our study was to investigate the difference between bone scan and PSMA-PET/CT for the detection of bone metastases in prostate cancer.

Methods

Thirty patients with bone metastases originating from prostate cancer were examined by ^99mTc-MDP bone scan and ⁶⁸Ga-PSMA-PET/CT within an average of 21 days. Bone scans were analyzed visually according to the number of lesions and using the software package ExiniBONE by Exini Diagnostics. PET/CT data was analyzed visually. Numbers of detected lesions were compared for the different methods for the whole patient and for different regions. In addition, results were compared to serum prostate-specific antigen (PSA), alkaline phosphatase (ALP), bone alkaline phosphatase (bALP), pro gastrin releasing peptide (pGRP) and eastern cooperative oncology group (ECOG) performance status.

Results

In the bone scans, visual and semiautomatic lesion detection showed similar results with an average of 19.4 and 17.8 detected bone lesion per patient. However, in PSMA-PET/CT, on average double the numbers of lesions (40.0) were detected. The largest differences were found in the thorax and pelvis, which can be explained by the advantages of tomographic imaging. Bland-Altman analysis showed greater differences in patients with large numbers of bone metastases.

Conclusion

No significant difference was found when using semiautomatic analysis compared to visual reading for bone scans. Fewer bone metastases were detected in bone scans than in PSMA-PET/CT. However, in none of our patients would the difference have led to clinical consequences. Therefore, it seems that for patients undergoing PSMA-PET/CT, there is no need to perform additional bone scans if the appropriate PET/CT protocols are applied.

SUBMITTER: Thomas L

PROVIDER: S-EPMC5620612 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Publications

Assessment of Bone Metastases in Patients with Prostate Cancer-A Comparison between <sup>99m</sup>Tc-Bone-Scintigraphy and [<sup>68</sup>Ga]Ga-PSMA PET/CT.

Thomas Lena L Balmus Caroline C Ahmadzadehfar Hojjat H Essler Markus M Strunk Holger H Bundschuh Ralph A RA

Pharmaceuticals (Basel, Switzerland) 20170731 3

<h4>Purpose</h4>Bone scintigraphy is the standard of reference in bone metastases in prostate cancer patients. However, new radiotracers employed in prostate-specific membrane antigen (PSMA)-ligands has led to the growing importance of PET/CT as diagnostic tool. The aim of our study was to investigate the difference between bone scan and PSMA-PET/CT for the detection of bone metastases in prostate cancer.<h4>Methods</h4>Thirty patients with bone metastases originating from prostate cancer were e ...[more]

PMID: 28758969

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Project description:BackgroundAndrogen 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.MethodsPatients 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).ResultsFifty 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).ConclusionFor 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.

Project description:BackgroundA number of radiopharmaceuticals are available for the detection of recurrent prostate cancer (rPC), but few comparative imaging trials have been performed comparing them. In particular, there are no prospective head-to-head comparisons of the recently introduced [18F]PSMA-1007 to the existing standard of care [68Ga]Ga-PSMA-11. The purpose of this trial is to establish the non-inferiority of the new radiopharmaceutical in terms of the rate of PET-positive findings and to obtain an intra-individual comparison of accuracy and radiopharmaceutical kinetics.MethodsIn this cross-over trial we will randomise 100 individuals to receive either first a standard-of-care PET/CT using [68Ga]Ga-PSMA-11 followed by an additional [18F]PSMA-1007 PET/CT within 2 weeks, or vice-versa. Inclusion criteria include patients 18 years and older with biochemical recurrence of prostate cancer following radical prostatectomy, defined as two consecutive prostate specific antigen (PSA) levels > 0.2 ng/ml. Detection rate at the patient-based level is the primary end-point. Each scan will be interpreted by a panel of six independent and masked readers (three for [68Ga]Ga-PSMA-11 and three for [18F]PSMA-1007) which consensus majority in cases of discrepancy. To confirm the PET-positivity rate at a patient based level, follow up at 6 months following the first scan will be performed to a composite standard of truth. Secondary endpoints shall include an intra-individual comparison of radiopharmaceutical-kinetics, per-region detection rate and positive predictive value.DiscussionThis is the first randomised prospective comparative imaging trial to compare the established [68Ga]Ga-PSMA-11 with [18F]PSMA-1007 and will determine whether the new radiopharmaceutical is non-inferior to the established standard-of-care in terms of patient-level detection rate.Clinical trial registrationRegistered with and approved by the regional ethics authority #2020-02903 (submitted 09.12.2020, approval 16.12.2021) and the regulatory authority SwissMedic 2020DR2103. Registered with ClinicalTrials.gov Identifier NCT05079828 and additionally in a national language in the Swiss National Clinical Trials Portal (SNCTP).

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Dataset Information

Assessment of Bone Metastases in Patients with Prostate Cancer-A Comparison between ^99mTc-Bone-Scintigraphy and [⁶⁸Ga]Ga-PSMA PET/CT.

Purpose

Methods

Results

Conclusion

Publications

Assessment of Bone Metastases in Patients with Prostate Cancer-A Comparison between <sup>99m</sup>Tc-Bone-Scintigraphy and [<sup>68</sup>Ga]Ga-PSMA PET/CT.

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OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

Assessment of Bone Metastases in Patients with Prostate Cancer-A Comparison between 99mTc-Bone-Scintigraphy and [68Ga]Ga-PSMA PET/CT.

Purpose

Methods

Results

Conclusion

Publications

Assessment of Bone Metastases in Patients with Prostate Cancer-A Comparison between <sup>99m</sup>Tc-Bone-Scintigraphy and [<sup>68</sup>Ga]Ga-PSMA PET/CT.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Assessment of Bone Metastases in Patients with Prostate Cancer-A Comparison between ^99mTc-Bone-Scintigraphy and [⁶⁸Ga]Ga-PSMA PET/CT.