RT Journal Article
SR Electronic
T1 <sup>18</sup>F-4FMFES and <sup>18</sup>F-FDG PET/CT in ER+ endometrial carcinomas: preliminary report
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP jnumed.121.262617
DO 10.2967/jnumed.121.262617
A1 Michel Paquette
A1 Esteban Espinosa-Bentancourt
A1 Eric Lavallee
A1 Serge Phoenix
A1 Korine Lapointe-Milot
A1 Paul Bessette
A1 Brigitte Guerin
A1 Eric E Turcotte
YR 2021
UL http://jnm.snmjournals.org/content/early/2021/08/19/jnumed.121.262617.abstract
AB In this study, the preliminary results of a phase II clinical trial investigating the use of the Estrogen Receptor (ER) targeting PET tracer 4-fluoro-11β-methoxy-16α-[18F]fluoroestradiol (18F-4FMFES) and [18F]-fluorodeoxyglucose (18F-FDG)-PET in endometrial cancers will be accounted. In parallel, non-invasive interventions will be attempted to slow down progression of 18F-4FMFES metabolites in the intestines to reduce abdominal background. Methods: In an ongoing study, 25 patients that received prior pathological confirmation of an ER+ endometrial cancer or endometrial intraepithelial neoplasia agreed to participate to the ongoing clinical trial. Patients were scheduled for 18F-FDG and 18F-4FMFES PET/CT imaging in random order and within 2 weeks. Patients were administered either 4 mg loperamide per os before 18F-4FMFES tracer injection or repeated intravenous injection of 20 mg hyoscine N-butylbromide during 18F-4FMFES-PET/CT. Regions-of-interest (ROIs) covering the whole abdomen and excluding the liver, bladder and uterus were drawn for the 18F-4FMFES-PET images, and a threshold of SUV &gt; 4 was applied. The volume of the resulting region was compared between the different interventions to estimate the extent of the intestinal background. Results: Repeated injection of hyoscine N-butylbromide substantially reduced the intestinal background volume, whereas loperamide had a significant but moderate effect. 18F-4FMFES tumor uptake ranged between SUVmax 3.0 and 14.4 (9.4 ± 3.2), whereas 18F-FDG uptake spreaded between SUVmax 0 and 22.0 (7.5 ± 5.1). Tumor-to-background ratio were significantly higher for 18F-4FMFES (16.4 ± 5.4) than for 18F-FDG (7.4 ± 4.6). Significant differences were observed between grade 1 and higher-grade tumors concerning 18F-4FMFES uptake and contrast. 18F-FDG uptake, and the 18F-FDG/18F-4FMFES uptake ratio. Conclusion: It is possible to improve 18F-4FMFES abdominal background using hyoscine N-butylbromide. Both 18F-FDG and 18F-4FMFES-PET are suitable for detection of ER+ endometrial cancers, although 18F-4FMFES yielded a better tumor contrast than 18F-FDG.