Nuklearmedizin 2020; 59(02): 125
DOI: 10.1055/s-0040-1708234
Wissenschaftliche Vorträge
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© Georg Thieme Verlag KG Stuttgart · New York

Preliminary results investigating the diagnostic efficacy of F-18-rhPSMA-7.3 PET imaging for N-staging of Patients with High Risk Prostate Cancer compared to histopathology

T Langbein
1   Klinikum rechts der Isar, Technische Universität München, Klinik und Poliklinik für Nuklearmedizin, München
,
M Krönke
1   Klinikum rechts der Isar, Technische Universität München, Klinik und Poliklinik für Nuklearmedizin, München
,
A Wurzer
2   Klinikum rechts der Isar, Technische Universität München, Lehrstuhl für Pharmazeutische Radiochemie, München
,
K Schwamborn
3   Klinikum rechts der Isar, Technische Universität München, Institut für Pathologie, München
,
H Wörther
1   Klinikum rechts der Isar, Technische Universität München, Klinik und Poliklinik für Nuklearmedizin, München
,
C Franz
1   Klinikum rechts der Isar, Technische Universität München, Klinik und Poliklinik für Nuklearmedizin, München
,
T Maurer
4   Universitätsklinikum Hamburg-Eppendorf, Martini-Klinik, Hamburg
,
T Horn
5   Klinikum rechts der Isar, Technische Universität München, Urologische Klinik und Poliklinik, München
,
HJ Wester
2   Klinikum rechts der Isar, Technische Universität München, Lehrstuhl für Pharmazeutische Radiochemie, München
,
WA Weber
1   Klinikum rechts der Isar, Technische Universität München, Klinik und Poliklinik für Nuklearmedizin, München
,
M Eiber
1   Klinikum rechts der Isar, Technische Universität München, Klinik und Poliklinik für Nuklearmedizin, München
› Author Affiliations
Further Information

Publication History

Publication Date:
08 April 2020 (online)

 

Ziel/Aim Radiohybrid PSMA (rhPSMA) ligands can be labeled with F-18 and radiometals and show only minimal renal excretion. rhPSMA-7 consists of four isomers (rhPSMA-7.1-rhPSMA-7.4) from which F-18-rhPSMA-7.3 was selected as lead compound for PET-imaging based on preclinical findings. We report first data investigating its histologically-confirmed efficacy for N-staging in patients with high risk prostate cancer.

Methodik/Methods 18 patients (median [range] PSA, 9.04 [4.3–20.8] ng/mL) underwent F-18-rhPSMA-7.3 PET-imaging (median [range] injected activity 338.5 [240–430] MBq; median [range] uptake time 74 [60–90] min) and were retrospectively rated by one experienced reader for the presence of lymph node metastases using a standard surgical template. Each anatomical field was rated on a five-point-scale independently for PET and for morphological imaging. Lesions were validated by histopathology after surgery on a patient- and template-basis.

Ergebnisse/Results Lymph node metastases were present in 5/18 patients (28 %), located in 5/102 templates (4.9 %). In the patient-based analysis, the sensitivity, specificity and accuracy of F-18-rhPSMA-7.3-PET were 60 %, 92.3 % and 83.3 %, respectively. For morphological imaging these were 20.0 %, 84.6 % and 66.7 %, respectively. For the template-based right vs. left analysis the sensitivity, specificity and accuracy of F-18-rhPSMA-7.3-PET were 60.0 %, 96.7 % and 91.4 %, and for morphological imaging 20.0 %, 93.3 % and 82.9 %, respectively. On ROC analyses, F-18-rhPSMA-7.3-PET showed a clear trend towards a better performance than morphological imaging on patient- and R vs. L-based analyses, yielding AUC values of 0.808 vs. 0.700 (p = 0.5583) and 0.823 vs. 0.560 (p = 0.2162), respectively.

Schlussfolgerungen/Conclusions Our preliminary data indicate that F-18-rhPSMA-7.3 PET might be superior to morphological imaging for N-staging of primary high risk prostate cancer. Analysis of data from a larger cohort is planned to investigate a potential significant difference.