In:
The British Journal of Radiology, British Institute of Radiology, Vol. 93, No. 1106 ( 2020-02-01), p. 20190735-
Abstract:
To assess the usefulness of a single-phase contrast-enhanced CT to differentiate subtypes of neuroendocrine tumour (NET) liver metastases and to evaluate the correlation between CT features and Ga-68 DOTATATE positron emission tomography/CT (PET/CT) findings. Methods: Between December 2017 and April 2019 patients with liver metastases of neuroendocrine tumours who underwent CT and Ga-68 DOTATATE PET/CT were enrolled in the study. All patients involved in the study had undergone a standardised single-phase contrast-enhanced CT. Whole body PET/CT images were obtained with a combined PET/CT scanner. All CT images were retrospectively analysed by two radiologists. Enhancement patterns of lesions were assessed. For quantitative examination; CT attenuation values of metastatic lesions, liver parenchyma and aorta were measured using a freehand ROI and tumour-to-liver ratio [T–L = (Tumour–Liver) / Liver] and tumour-to-aorta ratio [T–A = (Tumour–Aorta) / Aorta] were calculated. The lesion with the highest Ga-68 DOTATATE uptake in the liver was used for calculations. The metabolic tumour volume (MTV), maximum standardised uptake value (SUV max ) and SUV mean were calculated for the target liver lesion. Results: A total of 137 NET liver metastases divided into in three groups: 49 (35.7%) pancreatic, 60 (44.5%) gastroenteric and 26 (18.9%) lung NET liver metastases were analysed. Gastroenteric NET metastases often showed heterogeneous enhancement which was significantly higher than in the pancreas and lung NET liver metastases (p 〈 0.001). 96.72% (n = 59) of the gastroenteric NET liver metastases were hypoattenuating whereas the most frequent presentation for the pancreatic group was hyperattenuation (63.26%,n = 31). The difference in enhancement patterns of the liver metastases was statistically significant (p 〈 0.001) with respect to the location of the primary tumour. For quantitative analysis; tumour CT values were significantly different between the groups (p 〈 0.001). The T–L ratio was statistically different between gastroenteric and pancreatic NET liver metastases and pancreatic and lung NET groups (p 〈 0.001). The T–A ratio was significantly higher in the pancreatic NET metastases (p 〈 0.001). SUV max , SUV mean and MTV values, however, were not significantly different between the subgroups. There was a weak positive correlation between T–L ratio and SUV mean values. Conclusion: We noticed statistically significant differences in both qualitative and quantitative CT features between histologic subgroups of neuroendocrine tumour liver metastases at a single phase contrast-enhanced CT. Advances in knowledge: Our study will be the first in the literature which extensively focus on assessing the CT features of liver metastases of NETs at a single phase CT and Ga-68DOTATATE PET/CT. As the different histological subtypes of NET liver metastases exhibit different clinical outcomes, these features might help to identify the primary tumour to provide optimal treatment.
Type of Medium:
Online Resource
ISSN:
0007-1285
,
1748-880X
DOI:
10.1259/bjr.20190735
Language:
English
Publisher:
British Institute of Radiology
Publication Date:
2020
detail.hit.zdb_id:
1468548-6
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