RT Journal Article
SR Electronic
T1 3D Volumetric lymph node assessment based on CT versus PSMA-PET/CT in recurrent prostate cancer
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 1438
OP 1438
VO 56
IS supplement 3
A1 Frederik Giesel
A1 Hannah Fiedler
A1 Florian Sterzing
A1 Paul Flechsig
A1 Jan Moltz
A1 Ali Afshar-Oromieh
A1 Klaus Kopka
A1 Pete Choyke
A1 Uwe Haberkorn
A1 Clemens Kratochwil
YR 2015
UL http://jnm.snmjournals.org/content/56/supplement_3/1438.abstract
AB 1438 Objectives Radiopharmaceutical ChemistryPSMA-PET/CT is a powerful new method of detecting early nodal metastases in recurrent prostate cancer. The purpose of this retrospective investigation was to evaluate the volume and dimensions of nodes identified by Glu-urea-Lys-(Ahx)-[68Ga(HBED-CC)] (68Ga- PSMA-11) in the setting of recurrent prostate cancer.Methods All PET/CT image acquisitions were performed 60 ± 10 minutes after i.v. injection of 68Ga- PSMA-11 (mean dose 176 MBq). Forty nine PSMA-positive lymph nodes were identified in 21 patients with recurrent prostate cancer and rising PSA. Using a semi-automated lymph node segmentation software (MeVis, Bremen, GER), node volume and short and long axis dimensions were measured and compared to the maximum standardized uptake values (SUVmax). Round nodes greater than or equal to 0.8cm were considered positive by morphologic criteria alone. The percentage of nodes identified by elevated SUVmax but not by conventional morphologic criteria was determined.Results The mean volume of 68Ga-PSMA-positive nodes was 0,5 ml (range 2,3-0,2mL); mean short axis diameter was 5,8mm (range 2,4-13,3mm). In 7 patients (33,3%) with 31 PSMA positive nodes only 11(36%) were morphologically positive based on diameters >8mm on CT. In the remaining 14 patients (66,6%) 18 (37%) of PSMA positive lymph nodes had short axis diameters <8mm with a mean short axis diameter of 5,0mm (range 2,4-7,9).Conclusions 68Ga-PSMA-11 PET is more sensitive than CT based 3D volumetric lymph node evaluation in determining the node status of patients with recurrent prostate cancer and is a promising method of restaging prostate cancers in this setting.