Abstract
Ioannis Karfis1, Gwennaëlle Marin1, Hugo Levillain1, Stylianos Drisis2, Raoul Muteganya1, Gabriela Critchi1, Loubna Taraji-Schiltz1, Carlos Artigas Guix1, Leila Shaza3, Meriem Elbachiri3, Laura Mans3, Godelieve Machiels3, Alain Hendlisz3 and Patrick Flamen1
1 Nuclear Medicine Department, Institut Jules Bordet-Université Libre de Bruxelles (ULB), Brussels, Belgium
2 Radiology/Medical Imaging Department, Institut Jules Bordet-Université Libre de Bruxelles (ULB), Brussels, Belgium
3 Digestive Oncology Department, Institut Jules Bordet-Université Libre de Bruxelles (ULB), Brussels, Belgium
Correspondence to:
Ioannis Karfis, | email: | ioannis.karfis@bordet.be |
Keywords: gastroenteropancreatic neuroendocrine neoplasias; molecular imaging; prognostic biomarkers; 68Ga-DOTATATE PET/CT; 18F-FDG PET/CT
Received: October 02, 2019 Accepted: January 13, 2020 Published: February 11, 2020
ABSTRACT
We investigated on the added prognostic value of a three-scale combined molecular imaging with 68Ga-DOTATATE and 18F-FDG PET/CT, (compared to Ki-67 based histological grading), in gastroenteropancreatic neuroendocrine neoplasia patients. 85 patients with histologically proven metastatic gastroenteropancreatic neuroendocrine neoplasias, who underwent combined PET/CT imaging were retrospectively evaluated. Highest Ki-67 value available at time of 18F-FDG PET/CT was recorded. Patients were classified according to World Health Organization/European Neuroendocrine Tumor Society histological grades (G1, G2, G3) and into three distinct imaging categories (C1: all lesions are 18F-FDG negative/68Ga-DOTATATE positive, C2: patients with one or more 18F-FDG positive lesions, all of them 68Ga-DOTATATE positive, C3: patients with one or more 18F-FDG positive lesions, at least one of them 68Ga-DOTATATE negative). The primary endpoint of the study was Progression-Free Survival, assessed from the date of 18F-FDG PET/CT to the date of radiological progression according to Response Evaluation Criteria In Solid Tumors version 1.1. Classification according to histological grade did not show significant statistical difference in median Progression-Free Survival between G1 and G2 but was significant between G2 and G3 patients. In contrast, median Progression-Free Survival was significantly higher in C1 compared to C2 and in C2 compared to C3 patients, revealing three distinctive imaging categories, each with highly distinctive prognosis. Our three-scale combined 68Ga-DOTATATE/18F-FDG PET imaging classification holds high prognostic value in patients with metastatic gastroenteropancreatic neuroendocrine neoplasias.