TY - JOUR T1 - <strong>Preoperative 18F-FDG PET and MRI parameters in predicting histopathological features of endometrial cancer</strong> JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 356 LP - 356 VL - 61 IS - supplement 1 AU - Paola Mapelli AU - Gabriele Ironi AU - Alice Bergamini AU - Paola Maria Rancoita AU - Elena Venturini AU - Valerio Nisi AU - Federico Fallanca AU - Valentino Bettinardi AU - Anna Colarieti AU - Luca Bocciolone AU - Gianluca Taccagni AU - Luigi Gianolli AU - Francesco De Cobelli AU - Maria Picchio Y1 - 2020/05/01 UR - http://jnm.snmjournals.org/content/61/supplement_1/356.abstract N2 - 356Purpose: The aim of the present study is to explore the correlation between PET and MRI parameters of primary tumour and clinicopathological features, and to determine their predictive role in patients with endometrial cancer candidate to surgery. Methods: 27 patients with histologically proven endometrial cancer with preoperative 18F-FDG-PET and MRI scan, performed within one month one from the other, were retrospectively enrolled. The following primary tumour parameters have been considered: SUVmax, SUVmean, MTV and TLG for PET scan; ADCmean and Volume Index for MRI scans. FIGO stage, grade, hystotype (endometrioid vs not-endometrioid), myometrial invasion and lymphovascular space invasion (LVSI) were the histological parameters considered for the analysis. Results: MRI volume index showed a moderate direct correlation with SUVmax (rho=0.673; p&lt;0.001), SUVmean (rho=0.649; p&lt; 0.001), and TLG (rho= 0.669; p&lt; 0.001). A moderate inverse correlation was found between ADCmean and SUVmax (rho=-0.5; p=0.008), SUVmean (rho=-0.545; p=0.003) and TLG (rho=-0.481, p=0.011). MRI Volume index was a good predictor for myometrial invasion (AUC= 0.85; p= 0.003) and a fair predictor of LVSI (AUC= 0.74; p=0.039). Based on ROC curve analysis, a cut-off value of 9.555 for MRI volume index was predictive for deep myometrial invasion (sensitivity=84.6%; specificity= 76.9%); a cut-off higher than 12.165 was predictive for LVSI (sensitivity= 69.2%; specificity= 83.3%). A TLG cut-off value of 26.03 was predictive for myometrial invasion (sensitivity=84.6%; specificity=76.9%). When considering myometrial invasion as a continuous variable, a high direct correlation was found with MRI volume index (rho=0.722; p&lt; 0.001), while significant low direct correlation with SUVmax (rho=0.484; p= 0.012), SUVmean (rho=0.47; p= 0.015), and TLG (rho=0.482; p= 0.013) were identified. SUVmax/ADCmean ratio showed low direct correlation with the percentage of myometrial invasion (rho= 0.467; p= 0.016). Conclusions: MRI volume index and PET TLG are associated with deep myometrial invasion, as well as SUVmax/ADCmean ratio. As myometrial invasion is the conventional index used to predict lymph node involvement in endometrial cancer, the use of these imaging parameters might be suggested to predict lymphnodal metastases. ER -