PURPOSE: To evaluate the diagnostic accuracy of choline-PET/CT for nodal relapse of prostate cancer (PCA) according to topographical location and the size of tumor infiltration in lymph nodes (LN).
METHODS: 72 patients with nodal PCA-relapse after primary therapy underwent pelvic and/or retroperitoneal salvage lymph node dissection (salvage-LND) after a whole body PET/CT with 11C-Choline or 18F-Fluoroethylcholine showing PET-positive LN but no other detectable metastases. Diagnostic accuracy was evaluated for 160 dissected LN-regions (pelvic left/right, retroperitoneal), 498 subregions (common,-external,-internal-iliac, obturatoria, presacral, aortic-bifurcation, aortal, caval, interaortocaval) and 2122 LNs.
RESULTS: Lymph node metastases (LNM) were present in 32% of the resected LN (681/2122) resulting in 238 positive subregions and 111 positive regions. PET/CT was positive for 110 regions and 209 subregions. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy were: region-based 91.9%, 83.7%, 92.7%, 82.0% and 89.4%, subregion-based 80.7%, 93.5%, 91.9%, 84.1% and 87.3%, lesion-based 57.0%, 98.4%, 94.5%, 82.6% and 84.9%. 70.7% (278/393) of true positive LNM detected by PET/CT were located in LN with a short axis diameter < 10mm. Sensitivity of choline-PET/CT was 13.3%, 57.4% and 82.8% for depth of tumor infiltration of ≥2-< 3mm, ≥5-< 6mm and ≥10-< 11mm, respectively. Location of LNM and radiotracer (11C-choline/18F-fluoroethylcholine) had no substantial impact on diagnostic accuracy.
CONCLUSIONS: Choline-PET/CT detects affected LN-regions (left/right pelvic, retroperitoneal) in PCA-relapse with high accuracy and seems helpful for guiding salvage-LND. Sensitivity of choline-PET/CT decreases with the size of metastatic infiltration in LNs. Choline-PET/CT detects metastases in a significant fraction of LNs that are not pathologically enlarged on CT.
Written by:
Jilg CA, Schultze-Seemann W, Drendel V, Vach W, Wieser G, Krauss T, Jandausch A, Hölz S, Henne K, Reske SN, Grosu AL, Weber WA, Rischke HC. Are you the author?
Department of Urology, University of Freiburg, Germany; Department of Pathology, University of Freiburg, Germany; Department of Clinical Epidemiology, University of Freiburg, Germany; Department of Nuclear Medicine, University of Freiburg, Germany; Department of Radiology, University of Freiburg, Germany; Department of Radiation Oncology, Albert-Ludwigs University of Freiburg, Germany; Department of Nuclear Medicine University Ulm, Germany; Molecular Imaging and Therapy Service; Memorial Sloan-Kettering Cancer Center; New York, USA.
Reference: J Urol. 2014 Feb 8. pii: S0022-5347(14)00119-0.
doi: 10.1016/j.juro.2013.12.054
PubMed Abstract
PMID: 24518792
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