18F-FDG PET/CT-avid discordant volume as a biomarker in patients with gastroenteropancreatic neuroendocrine neoplasms – A multicentre study

#3681

Introduction: Dual 18F-FDG and 68Ga-DOTATATE PET/CT is emerging as a powerful technique to predict tumor biology. Whilst the presence of discordant disease (FDG avid/DOTA non-avid) predicts poor prognosis, it remains unknown whether the volume of discordant disease is also a significant predictor.

Aim(s): To determine if discordant tumor volume predicts prognosis in patients with advanced gastroenteropancreatic neuroendocrine neoplasms (GEPNEN).

Materials and methods: Multicentre retrospective study in patients with advanced GEPNEN and paired FDG and DOTATATE PET/CT <90 days apart. Patients identified by nuclear medicine review were manually contoured using MIM software (version 7.2.7). The primary endpoint was overall survival (OS). Total discordant volume (TDV), primary discordant volume, and metastatic discordant volume were dichotomised by the median into low vs high subgroups and compared using the log-rank test.

Conference:

Presenting Author: Chan D

Authors: Chan D, Hayes A, Karfis I, Conner A, Mileva M,

Keywords: prognostic biomarker, PET imaging, 18F-FDG, 68Ga-DOTATATE, dual PET, discordance,