Tara Diane Barwick MBChB, Presenter: Nothing to Disclose

Nishat Bharwani MBBS, FRCR, Abstract Co-Author: Nothing to Disclose

Sameer Khan MBBS, Abstract Co-Author: Nothing to Disclose

Marc Eric Miquel PhD, Abstract Co-Author: Nothing to Disclose

Andrea Grace Rockall MRCP, FRCR, Abstract Co-Author: Nothing to Disclose

1.Prospective evaluation of 18F-fluoroethylcholine (FEC) PET/CT in the detection of cervical and endometrial tumors 2.Degree of correlation with 18F-FDG PET/CT and whole tumor ADCmean (mean apparent diffusion co-efficient) on diffusion weighted (DW-) MRI

Sub-group analysis of patients prospectively recruited to the multi-centre MAPPING study (Eudra CT:2011-001290-78). Preliminary findings of 15 patients with surgically staged endometrial (n=6,FIGO stage 2-4B) and cervical cancer (n=9,FIGO stage 1B1-2B). The endometrial tumors were 5 endometrioid adenocarcinomas (grades 1 and 2) and 1 clear cell carcinoma. The cervical tumors were 4 squamous cell carcinomas (SCC), 3 adenosquamous tumors, 1 adenocarcinoma and 1 undifferentiated tumor. Each patient underwent DW-MRI, FDG and FEC PET/CT. The PET/CT studies were performed on consecutive days. The time interval between DW-MRI and first PET/CT was 0-17 days. 4 cervical cancer cases (all SCC) were excluded as the primary tumor was excised at cone biopsy leaving 11 for analysis. The correlation between tumor grade, FDG SUVmax, FEC SUVmax and ADCmean of the primary tumor were determined.

There were no adverse effects documented following the FEC administration. The primary tumor was visualized in 10/11 cases on FEC PET/CT and on all FDG PET/CT and DW-MRI studies. Mean SUVmax FEC (7.2±3.8) was significantly lower than mean SUVmax FDG (16.6±10.7;p=0.005) but there was a positive correlation between values (r=0.78). There was no correlation between ADCmean and FEC or FDG SUVmax (r=-0.35 and -0.24 respectively). When comparing high (G3) with low grade (G1+2) tumors there was a significant difference in whole tumor ADCmean (p=0.004) but no significant difference demonstrated in FEC or FDG SUVmax (p=0.25 & 0.28 respectively).

FDG PET/CT has been disappointing in staging early endometrial and cervical tumors. We have evaluated 18F-FEC, an alternative tracer which is effective in prostate cancer staging. Preliminary results show imaging of endometrial and cervical cancers with 18F-FEC is feasible. There is positive correlation with FDG uptake but in general tumor FEC SUVmax is lower than FDG SUVmax.

Preliminary results suggest that imaging of primary endometrial and cervical cancers with 18F-fluoroethylcholine PET/CT is feasible. Further evaluation is now required to assess staging accuracy.

Barwick, T, Bharwani, N, Khan, S, Miquel, M, Rockall, A, 18F-Fluoroethylcholine PET/CT in Endometrial and Cervical Tumors: First Experience and Comparison with 18F-FDG PET/CT and DW-MRI.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14015396.html