Assessment of diffusion-weighted MRI and 18F-fluoro-deoxyglucose PET/CT in monitoring early response to neoadjuvant chemotherapy in adenocarcinoma of the esophagogastric junction.

Background & Aims: To prospectively assess whether changes in apparent diffusion coefficient (ADC) values or standardized uptake value (SUV) changes in 18F-fluorodeoxyglucose (FDG) PET correlate with treatment response under neoadjuvant chemotherapy in patients with locally advanced adenocarcinoma of the esophagogastric junction (AEG).

Methods: Fifteen patients (median age, 64 years) with histologically proven AEG type I and II received 1.5 Tesla MRI including "diffusion-weighted imaging" and FDG PET/CT before and 14 days after neoadjuvant EOX chemotherapy.

Comparison of lesion detection and quantitation of tracer uptake between PET from a simultaneously acquiring whole-body PET/MR hybrid scanner and PET from PET/CT.

Purpose: PET/MR hybrid scanners have recently been introduced, but not yet validated. The aim of this study was to compare the PET components of a PET/CT hybrid system and of a simultaneous whole-body PET/MR hybrid system with regard to reproducibility of lesion detection and quantitation of tracer uptake.

Methods: A total of 46 patients underwent a whole-body PET/CT scan 1 h after injection and an average of 88 min later a second scan using a hybrid PET/MR system.