Evaluation of Diagnostic Criteria for Liver Metastases of Adenocarcinomas and Neuroendocrine Tumours at Conventional Ultrasound, Unenhanced Power Doppler Sonography and Echo-Enhanced Ultrasound

Abstract

Purpose: In order to improve the differential diagnosis between liver metastases of neuroendocrine tumours and adenocarcinomas, criteria for the masses at conventional ultrasound, unenhanced power Doppler sonography and echo-enhanced ultrasound were evaluated. Methods: Seventy-three patients with histologically proven liver metastases of a neuroendocrine tumour (n = 26) or an adenocarcinoma (n = 47) were investigated by conventional ultrasound as well as unenhanced power Doppler sonography and echo-enhanced ultrasound focusing on specific properties of the lesions. Results: Liver metastases of neuroendocrine tumours and adenocarcinomas showed a different contrast behaviour with echo-enhanced sonography. A hypervascularisation at the arterial and capillary phase were found in 85% of the neuroendocrine metastases, and in 17% of the masses of adenocarcinomas, respectively (p < 0.05). Conclusions: The successful treatment of liver metastases requires a highly sensitive and specific diagnostic procedure for their differentiation. A hypervascularisation of the lesions during the arterial and capillary phase at echo-enhanced ultrasound may point to a neuroendocrine primary tumour. However, histology is the only standard of reference for the differentiation of liver metastases, and is necessary for optimal therapy.

Usual and Unusual Neuroendocrine Tumor Metastases on 68Ga-DOTANOC PET/CT

“…1 Liver metastases arising from NET are predominantly hypervascular and have a tendency to present with multiple confluent lesions, although solitary and isolated lobar metastases have also been reported. 10 Metastatic liver deposits often show intense tracer uptake on SSTR imaging, and 68 Ga-DOTANOC PET-based imaging has been shown to be superior to both OctreoScan and CT in the detection of liver metastases 11 (Fig. 3).…”

Contrast-Enhanced Sonography for the Characterisation of Hepatocellular Carcinomas - Correlation with Histological Differentiation

“…Malignant liver tumours like liver metastases are characterised by an irregular vascularisation pattern in the arterial phase, fol-lowed by a reduced contrast enhancement in the portal and late phase in contrast-enhanced ultrasound [20]. The degree of tumour vascularity of liver metastases in the arterial phase depends on the histology of the primary tumour [21]. Hypervascular liver metastases of neuroendocrine tumours or melanomas show a very marked chaotic intratumoural vascularisation in the arterial phase, whereas in liver metastases of the gastrointestinal tract the degree of intratumoural vascularisation in the arterial phase is less pronounced, but still visable.…”

“…For the identification of liver metastases, the reduced contrast enhancement in the late phase (> 2 minutes after contrast application) is very helpful. Metastasic liver lesions show a markedly reduced tumour vascularity and contrast enhancement in comparison to the surrounding liver parenchyma in the late phase, which is very helpful for the characterisation and detection of liver metastases [21,22].…”

Detection of Hepatic Metastases from Carcinoid Tumor: Prospective Evaluation of Contrast-Enhanced Ultrasonography

“…However, liver metastases from carcinoid tumor still represent a challenge to imaging methods because they are often small and hyperechoic, thus mimicking hemangiomas. Although a few papers have reported neuroendocrine hepatic metastases features using CEUS [8][9][10], none has so far specifically evaluated CEUS in the detection of hepatic metastases. Magnetic resonance imaging (MRI) currently is the imaging modality which offers the highest diagnostic potential for assessment of liver involvement in patients with carcinoid tumor [11].…”