학술논문
Use of full-dose contrast-enhanced CT for extrahepatic staging using Gallium-68-DOTATATE PET/CT in patients with neuroendocrine tumors
Document Type
Report
Source
Diagnostic and Interventional Radiology. July 2021, Vol. 27 Issue 4, p573, 7 p.
Subject
Language
English
ISSN
1305-3825
Abstract
Previous studies have shown the importance of DOTATOC, DOTATATE, and DOTANOC PET/CT imaging in the diagnosis and accurate staging of neuroendocrine tumors (NET) (1-3). The use of radiolabeled somatostatin analogs [...]
PURPOSE Studies have demonstrated that positron emission tomography/computed tomography (PET/CT) with Gallium-68 ([.sup.68]Ga)-labeled somatostatin analogues are effective at detecting metastatic disease in neuroendocrine tumors (NET), especially extrahepatic metastases. However, PET in combination with full-dose contrast-enhanced CT (ceCT) exposes patients to higher radiation (~25 mSv). The use of non-contrast-enhanced low-dose CT (IdCT) can reduce radiation to about 10 mSv and may avoid contrast-induced side effects. This study seeks to determine whether ceCT could be omitted from NET assessments. METHODS We retrospectively compared the performance of PET/ldCT versus PET/ceCT in 54 patients (26 male, 28 female) who had undergone a [.sup.68]Ga-DOTATATE PET/CT. The selection criteria were as follows: available IdCT and ceCT, histologically confirmed NET, and follow-up of at least 6 months (median, 12.6 months; range, 6.1 -23.2 months). The PET/ldCT and PET/ceCT images were analyzed separately. We reviewed metastases in the lungs, bones, and lymph nodes. The results were compared with the reference standard (clinical follow-up data). RESULTS The PET/ceCT scans detected 139 true-positive bone lesions compared with 140 lesions detected by the PET/ldCT scans, 106 true-positive lymph node metastases (PET/ceCT) compared with 90 metastases detected by the PET/ldCT scans, and 26 true-positive lung lesions (PET/ceCT) compared with 6 lesions detected by the PET/ldCT scans. The overall lesion-based sensitivity for full-dose PET/ceCT was 97%, specificity 86%, negative predictive value (NPV) 93%, and positive predictive value (PPV) 93%. The overall lesion-based sensitivity for PET/IdCT was 85%, specificity 73%, NPV 72%, and PPV 85%. CONCLUSION This study presents the first evidence that ceCT should not be omitted from extrahepatic staging using [.sup.68]Ga-DOTATATE PET/CT in patients with NET. ceCT alone can be used as a follow-up to reduce radiation exposure when the patient has already undergone PET/ceCT and suffers from non-DOTATATE-avid NET.
PURPOSE Studies have demonstrated that positron emission tomography/computed tomography (PET/CT) with Gallium-68 ([.sup.68]Ga)-labeled somatostatin analogues are effective at detecting metastatic disease in neuroendocrine tumors (NET), especially extrahepatic metastases. However, PET in combination with full-dose contrast-enhanced CT (ceCT) exposes patients to higher radiation (~25 mSv). The use of non-contrast-enhanced low-dose CT (IdCT) can reduce radiation to about 10 mSv and may avoid contrast-induced side effects. This study seeks to determine whether ceCT could be omitted from NET assessments. METHODS We retrospectively compared the performance of PET/ldCT versus PET/ceCT in 54 patients (26 male, 28 female) who had undergone a [.sup.68]Ga-DOTATATE PET/CT. The selection criteria were as follows: available IdCT and ceCT, histologically confirmed NET, and follow-up of at least 6 months (median, 12.6 months; range, 6.1 -23.2 months). The PET/ldCT and PET/ceCT images were analyzed separately. We reviewed metastases in the lungs, bones, and lymph nodes. The results were compared with the reference standard (clinical follow-up data). RESULTS The PET/ceCT scans detected 139 true-positive bone lesions compared with 140 lesions detected by the PET/ldCT scans, 106 true-positive lymph node metastases (PET/ceCT) compared with 90 metastases detected by the PET/ldCT scans, and 26 true-positive lung lesions (PET/ceCT) compared with 6 lesions detected by the PET/ldCT scans. The overall lesion-based sensitivity for full-dose PET/ceCT was 97%, specificity 86%, negative predictive value (NPV) 93%, and positive predictive value (PPV) 93%. The overall lesion-based sensitivity for PET/IdCT was 85%, specificity 73%, NPV 72%, and PPV 85%. CONCLUSION This study presents the first evidence that ceCT should not be omitted from extrahepatic staging using [.sup.68]Ga-DOTATATE PET/CT in patients with NET. ceCT alone can be used as a follow-up to reduce radiation exposure when the patient has already undergone PET/ceCT and suffers from non-DOTATATE-avid NET.