Haïfa Bahri1, Lenoir Laurence2, Julien Edeline3, Houda Leghzali1, Anne Devillers1, Jean-Luc Raoul4, Marc Cuggia5, Habiba Mesbah6, Bruno Clement7, Eveline Boucher8, Etienne Garin9. 1. Department of Nuclear Medicine, Cancer Institute Eugène Marquis, Rennes, France. 2. Department of Nuclear Medicine, Cancer Institute Eugène Marquis, Rennes, France Inserm, UMR991, Liver Metabolisms and Cancer, Rennes, France University of Rennes 1, Rennes, France. 3. Inserm, UMR991, Liver Metabolisms and Cancer, Rennes, France University of Rennes 1, Rennes, France Department of Medical Oncology, Cancer Institute Eugène Marquis, Rennes, France. 4. Department of Medical Oncology, Comprehensive Cancer Center, Institute Paoli Calmette, Marseille, France. 5. Department of Medical Computing, CHU Pontchaillou, Rennes, France; and. 6. Department of Medical Informations, Cancer Institute Eugène Marquis, Rennes, France. 7. Inserm, UMR991, Liver Metabolisms and Cancer, Rennes, France. 8. Inserm, UMR991, Liver Metabolisms and Cancer, Rennes, France Department of Medical Oncology, Cancer Institute Eugène Marquis, Rennes, France. 9. Department of Nuclear Medicine, Cancer Institute Eugène Marquis, Rennes, France Inserm, UMR991, Liver Metabolisms and Cancer, Rennes, France University of Rennes 1, Rennes, France e.garin@rennes.unicancer.fr.
Abstract
UNLABELLED: This study aimed to evaluate the long-term prognostic usefulness of (18)F-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, (111)In-pentetreotide scintigraphy (SRS), and (18)F-FDG PET. Only (18)F-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 (18)F-FDG PET finding, with an OS of 119.5 mo (95% confidence interval [CI], 72-∞), than for patients with a positive (18)F-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 (18)F-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 (18)F-FDG PET. At 48-mo follow-up, 100% of patients who had a positive (18)F-FDG PET for disease progression (of which 47% were also SRS-positive) were deceased, and 87% of patients with a negative (18)F-FDG PET were alive (P < 0.0001). The T/NT ratio was the only parameter associated with OS on multivariate analysis. CONCLUSION: Overall, (18)F-FDG PET appears to be of major importance in the prognostic evaluation of metastatic GEPNET. A positive (18)F-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 (18)F-FDG PET, which is of greater prognostic utility.
UNLABELLED: This study aimed to evaluate the long-term prognostic usefulness of (18)F-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, (111)In-pentetreotide scintigraphy (SRS), and (18)F-FDG PET. Only (18)F-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 (18)F-FDG PET finding, with an OS of 119.5 mo (95% confidence interval [CI], 72-∞), than for patients with a positive (18)F-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 (18)F-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 (18)F-FDG PET. At 48-mo follow-up, 100% of patients who had a positive (18)F-FDG PET for disease progression (of which 47% were also SRS-positive) were deceased, and 87% of patients with a negative (18)F-FDG PET were alive (P < 0.0001). The T/NT ratio was the only parameter associated with OS on multivariate analysis. CONCLUSION: Overall, (18)F-FDG PET appears to be of major importance in the prognostic evaluation of metastatic GEPNET. A positive (18)F-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 (18)F-FDG PET, which is of greater prognostic utility.
Authors: Robert R Flavell; David M Naeger; Carina Mari Aparici; Randall A Hawkins; Miguel H Pampaloni; Spencer C Behr Journal: Radiographics Date: 2016 Jan-Feb Impact factor: 5.333