@article {Bahri1786, author = {Ha{\"\i}fa Bahri and Lenoir Laurence and Julien Edeline and Houda Leghzali and Anne Devillers and Jean-Luc Raoul and Marc Cuggia and Habiba Mesbah and Bruno Clement and Eveline Boucher and Etienne Garin}, title = {High Prognostic Value of 18F-FDG PET for Metastatic Gastroenteropancreatic Neuroendocrine Tumors: A Long-Term Evaluation}, volume = {55}, number = {11}, pages = {1786--1790}, year = {2014}, doi = {10.2967/jnumed.114.144386}, publisher = {Society of Nuclear Medicine}, abstract = {This study aimed to evaluate the long-term prognostic usefulness of 18F-FDG PET for patients with metastatic gastroenteropancreatic neuroendocrine tumors (GEPNETs). Methods: Thirty-eight patients with metastatic GEPNETs were prospectively enrolled. Initial check-up comprised CT scan, 111In-pentetreotide scintigraphy (SRS), and 18F-FDG PET. Only 18F-FDG PET{\textendash}positive lesions with a maximum standardized uptake value (SUVmax) greater than 4.5 or an SUV ratio (SUVmax tumor to SUVmax nontumoral liver tissue, or T/NT ratio) of 2.5 or greater were considered positive for prognosis{\textemdash}that is, indicating a poor prognosis. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan{\textendash}Meier method. Factors associated with survival were assessed with univariate and multivariate analyses, using the Cox regression model. Results: Median PFS and OS were significantly higher for patients with a negative 18F-FDG PET finding, with an OS of 119.5 mo (95\% confidence interval [CI], 72{\textendash}$\infty$), than for patients with a positive 18F-FDG PET finding (only 15 mo [95\% CI, 4{\textendash}27]) (P \< 10-3). Median PFS and OS were significantly higher for the patient group that had a positive SRS than the group with a negative SRS (P = 0.0002). For patients with a positive SRS, PFS and OS were significantly shorter when the 18F-FDG PET finding was positive: 19.5 mo (95\% CI, 4{\textendash}37) for PFS and 119.5 mo (95\% CI, 81{\textendash}$\infty$) for OS (P \< 10-3). In the patient group with a low-grade GEPNET and a positive SRS, PFS and OS were also significantly lower for patients with a positive 18F-FDG PET. At 48-mo follow-up, 100\% of patients who had a positive 18F-FDG PET for disease progression (of which 47\% were also SRS-positive) were deceased, and 87\% of patients with a negative 18F-FDG PET were alive (P \< 0.0001). The T/NT ratio was the only parameter associated with OS on multivariate analysis. Conclusion: Overall, 18F-FDG PET appears to be of major importance in the prognostic evaluation of metastatic GEPNET. A positive 18F-FDG PET with an SUV ratio (T/NT) of 2.5 or greater was a poor prognostic factor, with a 4-y survival rate of 0\%. A positive SRS does not eliminate the need for performing 18F-FDG PET, which is of greater prognostic utility.}, issn = {0161-5505}, URL = {https://jnm.snmjournals.org/content/55/11/1786}, eprint = {https://jnm.snmjournals.org/content/55/11/1786.full.pdf}, journal = {Journal of Nuclear Medicine} }