Discordance of Dual-Tracer PET/CT with Histopathology in a Grade I Pancreatic Neuroendocrine Tumor: A Diagnostic Conundrum

Abstract

Objectives

Neuro endocrine tumors (NETs) demonstrate complex biology where imaging and histology can at times show discordance in a real-world scenario.

Materials and Methods

We herein present a patient of grade I pancreatic NET showing atypical low somatostatin receptor expression on ⁶⁸Ga-DOTATATE PET/CT (positron emission tomography/computed tomography) but intense fluorine-18-deoxyglucose (¹⁸FDG) avidity, and when interpreted together, these findings showed discordance with histopathology.

Results

The case highlights the crucial role of dual-tracer PET/CT in navigating the tumor biology and landscape of NET and the need for novel strategies to complement traditional histopathology that would enable better therapeutic decision-making.

Keywords

neuroendocrine tumors - ¹⁷⁷Lu-DOTATATE PRRT - ⁶⁸Ga-DOTATATE PET/CT - somatostatin receptor (SSTR) - fluorine-18-deoxyglucose (¹⁸FDG) - dual-tracer PET/CT

Publication History

Article published online:
04 October 2025

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