Contrast-Enhanced Ultrasound Findings in Patients with Rare Solitary Necrotic Nodule of the Liver – a Multicenter Report

Abstract

Purpose This multicenter retrospective study highlights the contrast-enhanced ultrasound (CEUS) findings in a series of histologically proven solitary necrotic nodules (SNN) of the liver, a poorly understood pathologic entity of uncertain origin that mimics malignancy. Materials and Methods 22 patients (M/F 13/9; mean age 59.4 years, SD ± 10.7, range 35–81) with histological diagnosis of SNN and CEUS were selected from clinical, imaging, and pathological archives of 7 US interventional centers, each of which provided 1 to 6 cases (mean 2.8). Pathological diagnosis was made on 20 US-guided biopsies and 2 surgical specimens. 2 patients had 2 SNNs with identical CEUS findings so that imaging analysis was carried out on 24 nodules. Results SNN was an incidental finding in healthy people in 10 cases (45.5 %), and it was discovered during follow-up for either known extrahepatic malignancies (9 cases = 41 %) or chronic liver disease (3 cases = 13.5 %). SNNs had a mean size of 19.3 mm (SD ± 6.5, range 9–40). On B-mode US, SNNs appeared hypoechoic in 14 cases (66.7 %), “target-like” in 7 cases (29.2 %), and homogeneously hyperechoic in 1 case (4.1 %). On CEUS, all lesions appeared devoid of contrast enhancement (“punched out” aspect) in the arterial, portal venous, and late phases after US contrast agent injection. A uniformly thin, hyperenhancing ring in the early arterial phase and isoenhanced with the surrounding parenchyma in the portal venous and late phases was found in 10 nodules (41.6 %). Clinical and imaging follow-up (mean duration 42.2 months, SD ± 34.9, range 2–108) was available in 15 patients with 16 SNNs: no changes in size and echostructure were seen. Conclusion CEUS can contribute to the diagnosis of SNN when a “punched out” appearance in all vascular phases with or without thin rim enhancement in the very early arterial phase is present in healthy subjects in whom a focal liver lesion is incidentally found. In patients with a history of chronic liver disease or malignancy, US-guided biopsy represents the unavoidable first-line diagnostic modality.

The analysis of contrast-enhanced ultrasound features of the liver in male patients with liver cancer and unhealthy life habits under 50 years-of-age

“…Thus, after injection, contrast shows fast enhancement in tumors, and fast clearance in the advanced arterial phase [20][21][22]. These findings are related to the fact that the abundant blood supply of the hepatic artery and the formation of new blood vessels can accelerate micro-vascular perfusion and blood circulation, thus resulting in a shorter circulation time for contrast agents during the advanced arterial phase [23][24][25]. In this study, we also found that the sensitivity, specificity and accuracy of CEUS for the diagnosis of liver cancer were 91.67%, 95.51% and MVI and the differentiation grade of cancer lesions are important factors that can affect the prognosis and treatment of liver cancer.…”

Spontaneous hepatic rupture during late pregnancy in a patient with solitary necrotic nodule of the liver: A case report

“…Preoperative imaging examination to monitor the lesion is of great importance. SNNL usually presents as heterogeneous hypoechoic nodules on ultrasonography with unclear edges ( 11 ). Enhanced MRI is helpful to distinguish SNNL from other lesions.…”

Solitary necrotic nodules of the liver with "ring"-like calcification: A case report

“…has an important influence on the treatment option. Hypoechoic nodules normally appear on abdominal ultrasound of SNNL[ 12 ], hepatic parenchymal tuberculosis[ 13 ], and liver metastatic tumors. Ultrasound has certain limitations in the differential diagnosis of solitary liver nodules.…”