Dual tracer functional imaging of gastroenteropancreatic neuroendocrine tumors using 68Ga-DOTA-NOC PET-CT and 18F-FDG PET-CT: competitive or complimentary?
OBJECTIVE
This study aimed to compare the diagnostic performance of Ga-DOTANOC PET/CT with F-FDG PET/CT in the patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs).


METHODS
Data of 51 patients with definite histological diagnosis of GEP-NET who underwent both Ga-DOTA-NOC PET-CT and F-FDG PET-CT within a span of 15 days were selected for this retrospective analysis. Sensitivity, specificity, and predictive values were calculated for Ga-DOTA-NOC PET-CT and F-FDG PET-CT, and results were compared both on patientwise and regionwise analysis.


RESULTS
Ga-DOTA-NOC PET-CT is superior to F-FDG PET-CT on patientwise analysis (P < 0.0001). On regionwise analysis, Ga-DOTA-NOC PET-CT is superior to F-FDG PET-CT only for lymph node metastases (P < 0.003). Although Ga-DOTA-NOC PET-CT detected more liver and skeletal lesions compared with F-FDG PET-CT, the difference was not statistically significant. In addition, the results of combined imaging helped in selecting candidates who would undergo the appropriate mode of treatment, whether octreotide therapy or conventional chemotherapy


CONCLUSIONS
Ga-DOTA-NOC PET-CT seems to be superior to F-FDG PET-CT for imaging GEP-NETs. However, their role seems to be complementary because combination of Ga-DOTA-NOC PET-CT and F-FDG PET-CT in such patients helps demonstrate the total disease burden and segregate them to proper therapeutic groups.
From the Department of Nuclear Medicine, All India Institute of Medical Sciences, New Delhi, India.
Niraj
N
Naswa
Punit
P
Sharma
Santosh Kumar
SK
Gupta
Sellam
S
Karunanithi
Rama Mohan
RM
Reddy
Manish
M
Patnecha
Sneh
S
Lata
Rakesh
R
Kumar
Arun
A
Malhotra
Chandrasekhar
C
Bal
D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007414:Intestinal Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D009362:Neoplasm Metastasis; D018358:Neuroendocrine Tumors / Q000000981:diagnostic imaging* / Q000473:pathology; D009942:Organometallic Compounds; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D049268:Positron-Emission Tomography / Q000379:methods*; D011849:Radioactive Tracers; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D014057:Tomography, X-Ray Computed / Q000379:methods*
C504894:68Ga-DOTANOC; D009942:Organometallic Compounds; D011849:Radioactive Tracers; D019788:Fluorodeoxyglucose F18