Comparison of 18F-FDG and 68Ga-DOTA-NOC PET/CT on the diagnosis of G3 neuroendocrine neoplasm / 中华核医学与分子影像杂志

ABSTRACT

Objective To investigate the clinical value of 18F-FDG PET/CT in diagnosing G3 NEN and compare it with 68Ga-DOTA-NOC PET/CT.Methods Twenty-three patients (12 males,11 females;average age (63± 12) years) diagnosed of NEN between January 2006 and November 2016 were retrospectively recruited in this study:11 patients with gastroenteropancreatic NEN (GEP-NEN),10 with G3 NEN in lungs,1 with malignant pheochromocytoma and 1 with G3 NEN of unknown primary site.All patients underwent 18F-FDG PET/CT for staging and evaluation of biological behavior,and 9 of them also underwent 68Ga-DOTA-NOC PET/CT within 1 week.Image interpretation was analyzed by visual and semi-quantitative analysis,and SUVmax was calculated.Results All 23 cases showed positive results on 18F-FDG PET/CT (100％,23/23),with primary tumor SUVmax 10.56±3.94.Compared with 18F-FDG PET/CT,the positive detection rate of 68Ga-DOTA-NOC PET/CT was lower (6/9 vs 9/9),with primary tumor SUVmax 14.24± 10.00.There were 22 patients with distant metastasis.The most frequent metastatic sites associated with G3 NEN in lungs were lymph nodes and bones,while those with GEP-NEN were lymph nodes and the liver.In one patient with non-functional NEN,some metastatic lesions showed negative results on 18F-FDG PET/CT but positive results on 68 Ga-DOTA-NOC PET/CT.Conclusions 18 F-FDG PET/CT has higher diagnostic ability for G3 NEN and may serve as a useful tool for evaluating biological behavior of G3 NEN.68Ga-DOTA-NOC PET/CT is valuable as a complementary diagnostic tool in a small proportion of high differentiated G3 NEN.