Tibor Vag MD, PhD, Presenter: Nothing to Disclose

Matthias Heck, Abstract Co-Author: Nothing to Disclose

Ernst J. Rummeny MD, Abstract Co-Author: Nothing to Disclose

Markus Schwaiger MD, Abstract Co-Author: Research Grant, Siemens AG

Matthias Johannes Eiber MD, Abstract Co-Author: Speaker, Siemens AG Speaker, Astellas Group Speaker, Johnson & Johnson

To compare diagnostic performance of DWI and [11C]-Choline PET/CT in the assessment of preoperative lymph node status in patients with primary prostate cancer.

33 patients underwent DWI and [11C]-Choline PET/CT prior to prostatectomy and extended pelvic lymph node dissection. Mean standardized 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.

A significant difference between benign and malignant LN was observed for ADC-values (1.17 vs. 0.96x10-3mm2/s; P<0.001) and SUVmean (1.61 vs. 3.20; P<0.001). ROC analysis revealed an optimal ADC threshold of 1.01x10-3mm2/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).

Both modalities reveal similar moderate diagnostic performance for pre-operative lymph-node staging of prostate cancer. The only moderate inverse correlation between ADC-values and SUVmean suggests that both imaging parameters might provide complementary information on tumour biology.

The application of both modalities in routine preoperative lymph node staging of primary prostate cancer ist not justified at this time.    

Vag, T, Heck, M, Rummeny, E, Schwaiger, M, Eiber, M, Lymph Node Staging in Patients with Primary Prostate Cancer: Comparison of Quantitative Imaging Parameters in Diffusion Weighted Imaging and [11C]-Choline PET/CT.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14007537.html