RT Journal Article SR Electronic T1 High Prognostic Value of 18F-FDG PET for Metastatic Gastroenteropancreatic Neuroendocrine Tumors: A Long-Term Evaluation JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 1786 OP 1790 DO 10.2967/jnumed.114.144386 VO 55 IS 11 A1 Haïfa Bahri A1 Lenoir Laurence A1 Julien Edeline A1 Houda Leghzali A1 Anne Devillers A1 Jean-Luc Raoul A1 Marc Cuggia A1 Habiba Mesbah A1 Bruno Clement A1 Eveline Boucher A1 Etienne Garin YR 2014 UL http://jnm.snmjournals.org/content/55/11/1786.abstract AB 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–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—that is, indicating a poor prognosis. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan–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–∞), than for patients with a positive 18F-FDG PET finding (only 15 mo [95% CI, 4–27]) (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, 4–37) for PFS and 119.5 mo (95% CI, 81–∞) 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.