11C-Choline PET-CT and multiparametric NMR in the diagnosis of primary prostate cancer

Objectives To analyse the contribution of 11C-Choline PET/CT and multiparametric NMR in primary prostate cancer previously to a radical prostatectomy.Findings were correlated with anatomopathological results(AP)

Methods 16 untreated patients(median 62 years range 52-72) and scheduled for radical prostatectomy were studied by means of a quantitative 11C-Choline PET, and multiparametric NMR sequences (T2-DWI-Choline/CitrateRatio). Both techniques were performed on a Biograph-mCT 64-UltraHD-PET and a 3T-MR(Trio). A correlation analysis for tumor(T) and non tumor(NT) in both imaging parameters and histopathological data was performed (Cohen's Kappa test). All focal uptake findings in PET (FUF) (n=42) and one selected normal area in each patient (n=16) were quantified by means of 58 VOIs to calculate SUVMax, SUVmin, and M/m Ratio. Sensitivity (S), Specificity (Sp) were calculated.Wilcoxon test was applied to evaluate M/m differences. ROC curves were also performed

Results From 42 FUF, 32 were considered T and 10 NT in AP. 15 T lesions were detected in both imaging techniques. On the contrary 16 T positives in PET were non detected by T2 or by DWI. A correlation between PET and the increase of Cho/Cit was proved in 18 FUF. Significant differences in M/mR (p=0.005) were detected between 26 NT and 32 T(1.79 range:1-4.66) and (2.53 range:1.39-6.48) respectively. Cut-off M/mR calculated for malignancy (ROCcurves) in 58 VOIs was 1.8(AUC=0.77 p<0.001)(S=87.5%;Sp=61.5%). An improvement in this analysis was found in coincident lesions on PET and NMR (Cut-off=1.8;AUC=0.88 p<0.001)(S=100%;Sp=75%)

Conclusions Quantification of 11C-Choline in a high resolution PET-CT is a reliable procedure to detect primary prostate cancer.A combined analysis of PET and multiparametric NMR improved the results of both techniques to characterize intraprostatic lesions