Hongzan Sun, Presenter: Nothing to Disclose

Jun Xin MD, Abstract Co-Author: Nothing to Disclose

Shaomin Zhang, Abstract Co-Author: Nothing to Disclose

Qiyong Guo MD, Abstract Co-Author: Nothing to Disclose

To evaluate the concordance of imaging by [18F] fluorodeoxyglucose (FDG) - positron emission tomography (PET), T2 weighted imaging (T2WI) and apparent diffusion coefficient (ADC) maps with diffusion-weighted imaging (DWI) in cervical cancer using hybrid whole-body PET/MRI.

Cervical cancer patients (N=35) were prospectively recruited to undergo pretreatment 18FDG-PET/MRI. 18FDG-PET and MRI images were fused using standard software. The percent of the maximum standardized uptake value (SUVmax) was used to contour tumors on PET images and volumes were auto calculated. Tumor volumes measured by T2WI and DWI were calculated with standard techniques of tumor area multiplying slice profile. Data analysis used parametric statistics.

The mean tumor volumes calculated using SUVmax (14.30 ± 4.70) and T2WI (33.81 ± 27.32 cm3) were similar (P > 0.05) at 35% and 40% of SUVmax and significantly correlated (P ＜ 0.001; r = 0.735 and 0.766). The mean DWI volume was 30.48 ± 22.41cm3. DWI volumes were not significantly different from FDG PET volumes (at 35% SUVmax or 40% SUVmax) or T2WI volumes (P > 0.05). PET subvolumes with increasing percentage cutoff showed an inverse change of mean ADC value on DWI (P < 0.001, ANOVA), which indicated that regions with increased metabolic activity on FDG-PET also had more restricted diffusion on DWI.

Hybrid PET/MRI showed strong concordance between FDG-PET, T2WI and DWI in cervical cancer. Cutoff at 35% or 40% of SUVmax is recommended during 18FDG PET-MRI SUV-based tumor volume estimation. Tumor subvolumes with increased metabolic activity on FDG-PET also have greater cell density by DWI.

Hybrid PET/MRI was demonstrated a reliable method in cervical cancer imaging, and will benefit its clinical decision making by combining accordant anatomical and functional information together. 

Sun, H, Xin, J, Zhang, S, Guo, Q, Anatomical and Functional Volume Concordance between FDG-PET, T2 and Diffusion Weighted MRI for Cervical Cancer: A Hybrid PET/MRI Study.  Radiological Society of North America 2013 Scientific Assembly and Annual Meeting, December 1 - December 6, 2013 ,Chicago IL. http://archive.rsna.org/2013/13015045.html