Evaluation of Liver Tumors Using Acoustic Radiation Force Impulse Elastography and Correlation With Histologic Data

Abstract

Objectives Acoustic radiation force impulse (ARFI) technology represents an innovative method for the quantification of tissue elasticity. The aims of this study were to evaluate elasticity by ARFI in both liver tumors and background liver tissue and to compare ARFI measurements with histologic data in liver tumors and background liver. Methods Seventy‐nine tumors were prospectively studied: 43 benign and 36 malignant. Acoustic radiation force impulse measurements for each tumor type were expressed as mean ± standard deviation for both liver tumors and background liver; ARFI data were also correlated with histologic data. Results For liver tumors, the mean stiffness values were 1.90 ± 0.86 m/s for hepatocellular adenoma (n = 9), 2.14 ± 0.49 m/s for hemangioma (n = 15), 3.14 ± 0.63 m/s for focal nodular hyperplasia (n = 19), 2.4 ± 1.01 m/s for hepatocellular carcinoma (n = 24), and 3.0 ± 1.36 m/s for metastasis (n = 12). Important variations were observed within each tumor type or within a single tumor. These variations could have been due to necrosis, hemorrhage, or colloid. There was no statistically significant difference between the benign and malignant groups. Regarding background liver, it was possible to observe pathologic abnormalities in histologic analyses or liver function tests to explain the ARFI data. The degree of fibrosis was not the only determinant of liver stiffness in background liver; other factors such as portal embolization, sinusoidal obstruction syndrome caused by chemotherapy, and cholestasis, also could have interfered. Conclusions Acoustic radiation force impulse elastography could not allow differentiation between benign and malignant tumors. This study provides a better understanding of the correlation between ARFI and histologic data for both tumors and background liver.

Focal nodular hyperplasia of the liver: an emerging complication of hematopoietic SCT in children

“…In addition, we evaluated the degree of hepatic fibrosis in FNH patients with a quite recently introduced, noninvasive imaging technique, liver FibroScan. 15,16,38 We also tried to identify any relationship between fibrosis and nodules' size and number. We found out that the majority of FNH patients who underwent FibroScan (75%) had a moderate degree of LS not correlated with nodules' characteristics.…”

Aim: To investigate the value of ElastPQ measurement for differential diagnosis of benign and malignant focal liver lesions (FLLs) by using histologic results as a reference standard. Material and methods: A total of 154 patients were included. ElastPQ measurement was performed for each lesion in which the shear wave speed (SWS) was measured. The difference in SWS and SWS ratio of FLL to surrounding liver were evaluated, and the cut off value was investigated. Receiver operating characteristic (ROC) curve

“…Stiffness of liver metastasis depends on the amount of fibrous and vessels of the tumor [5] and the type of primary tumor [15]. Metastases which were undergoing treatment with chemotherapy and/or anti-angiogenic therapy could affect their stiffness [12,25].…”

“…Most of them used ARFI technology [13][14][15], some with 2D SWE using Aixplorer (SuperSonic Imagine, France) [16]. Their re-sults showed that SWE have a relevant diagnostic role in clinical practice [12,14,[17][18][19].…”

Reply

“…Indeed, in our article, 1 we made an error in terminology by misuse of language in calling the shear wave velocity (SWV), in units of meters per second, tissue stiffness. As Urban et al point out, after reviewing literature, similar errors had been made in scientific articles concerning ARFI, using inappropriate terms such as "liver stiffness (m/s)," "liver elasticity (m/s)," "mean liver stiffness value (m/s)," and "ARFI liver stiffness (m/s)" instead of SWV (m/s), whereas the units are different.…”