neuroendocrine tumors

tomography pet

radionuclide therapy

fdg pet

peptide receptor

ct imaging

prostate-specific membrane antigen

pet mri

fdg uptake

dotatate pet

Endokrynologia Polska

Introduction:  Peptide receptor radionuclide therapy (PRRT) using radiolabelled somatostatin analogues is a treatment option for patients with disseminated neuroendocrine tumours (NET). The aim of the study was the evaluation of the role of [ 18 F]FDG PET/CT in predicting response, progression-free survival (PFS) and overall survival (OS) after tandem therapy [ 90 Y]Y/[ 177 Lu]Lu-DOTATATE.   Material and methods:  Seventy-five patients with histopathologically proven NET G1 and G2 were included in the study. Before treatment [ 68 Ga]Ga-DOTATATE PET/CT and [ 18 F]FDG PET/CT was performed. Patients were treated with [ 90 Y]Y/[ 177 Lu]Lu-DOTATATE (1:1) with mixed amino-acid infusion for kidney protection.   Results:  Progression-free survival was 22.2 months for [ 18 F]FDG-positive patients and 59.3 months for [ 18 F]FDG-negative patients (p = 0.003). The OS from diagnosis (OS-D) and from the start of PRRT (OS-T) was not reached in [ 18 F]FDG-negative patients, and in [ 18 F]FDG-positive patients it was 71.8 months and 55.8 months, respectively. The observed overall one-year survival in [ 18 F]FDG-positive  vs.  [ 18 F]FDG-negative patients was 96.8%  vs.  99.1%, two-year survival was 88.9%  vs.  96%, and five-year survival was 58.8%  vs.  88%, respectively. The one-year and two-year risk of progression was 15%  vs.  58.9% in [ 18 F]FDG-positive patients and 11%  vs.  32% in [18F]FDG-negative patients. The objective response rate (ORR) [ 18 F]FDG-positive  vs.  [ 18 F]FDG-negative patients was 41.7%  vs.  17%.   Conclusions:  [ 18 F]FDG-positive patients have statistically significant shorter survival parameters than [ 18 F]FDG-negative patients. The risk of progression in [ 18 F]FDG-positive  vs.  [ 18 F]FDG-negative patients in one-year follow-up is comparable, whereas in two-year follow-up it is nearly two times higher for [ 18 F]FDG PET/CT-positive patients.

Effect of Peptide Receptor Radionuclide Therapy (PRRT) with tandem isotopes – [90Y]Y/[177Lu]Lu-DOTATATE in patients with disseminated neuroendocrine tumours depending on qualification [18F]FDG PET/CT in Polish multicenter experience – do we need [18F]FDG