PURPOSE: To compare the diagnostic performance of DWI and 11C-choline PET/CT in the assessment of preoperative lymph node status in patients with primary prostate cancer.
MATERIAL AND METHODS: Thirty-three patients underwent DWI and 11C-choline PET/CT prior to prostatectomy and extended pelvic lymph node dissection. Mean standardised uptake value (SUVmean) and mean apparent diffusion coefficient (ADC) of 76 identified lymph nodes (LN) were measured and correlated with histopathology. ADC values and SUVs were compared using linear regression analysis.
RESULTS: A significant difference between benign and malignant LN was observed for ADC values (1.17 vs. 0.96 × 10-3 mm2)/s; P < 0.001) and SUVmean (1.61 vs. 3.20; P < 0.001). ROC analysis revealed an optimal ADC threshold of 1.01 × 10-3 mm2/s for differentiating benign from malignant LN with corresponding sensitivity/specificity of 69.70 %/78.57 % and an area under the curve (AUC) of 0.785. The optimal threshold for SUVmean was 2.5 with corresponding sensitivity/specificity of 69.72 %/90.48 % and with an AUC of 0.832. ADC values and SUVmean showed a moderate significant inverse correlation (r = -0.63).
CONCLUSION: Both modalities reveal similar moderate diagnostic performance for preoperative lymph node staging of prostate cancer, not justifying their application in routine clinical practice at this time. The only moderate inverse correlation between ADC values and SUVmean suggests that both imaging parameters might provide complementary information on tumour biology.
Written by:
Vag T, Heck MM, Beer AJ, Souvatzoglou M, Weirich G, Holzapfel K, Krause BJ, Schwaiger M, Eiber M, Rummeny EJ. Are you the author?
Clinic of Nuclear Medicine, Klinikum Rechts der Isar, Technical University Munich, Ismaninger Strasse 22, 81675, Munich, Germany.
Reference: Eur Radiol. 2014 Aug;24(8):1821-6.
doi: 10.1007/s00330-014-3240-8
PubMed Abstract
PMID: 24889997
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