Assessment of Liver Fibrosis With Elastography Point Quantification vs Other Noninvasive Methods

Abstract

Background & aims: Elastography point quantification (ElastPQ) is a non-invasive method for assessing liver fibrosis based on liver stiffness. We evaluated the accuracy of ElastPQ for the staging of liver fibrosis in patients with chronic liver disease (CLD) compared with aspartate transaminase to platelet ratio index, fibrosis-4 index, and transient elastography (TE), using liver biopsy as reference standard.

Methods: We performed a retrospective study of 406 patients with CLD of any etiology who underwent liver biopsy analysis from September 2012 through June 2017 at a clinic in Bologna, Italy. We obtained liver stiffness measurements, made by ElastPQ and TE, for 361 patients. Liver fibrosis stage was assessed by the METAVIR scoring system. Areas under the receiver operating characteristic curve (AUROC) were used to assess the diagnostic performance of ElastPQ.

Results: ElastPQ values correlated with histologic detection of fibrosis (r = 0.718; P < .001). The AUROC values were 0.856 for detection of significant fibrosis (F≥2), 0.951 for advanced fibrosis (F≥3), and 0.965 for cirrhosis. The best cut-off values identified for classifying patients with F≥2, F≥3, or cirrhosis were 6.0 kPa, 6.2 kPa, and 9.5 kPa, respectively: these were lower than those for TE. Comparison of ElastPQ with TE data resulted in superimposable diagnostic accuracy of both methods for each stage of liver fibrosis. Both elastography techniques performed better than aspartate transaminase to platelet ratio index or fibrosis-4 index scores (P < .05 for all AUROC comparisons).

Conclusions: ElastPQ has good to excellent performance for the non-invasive staging of liver fibrosis in patients with CLD. ElastPQ identified patients with fibrosis or cirrhosis with levels of accuracy that were not inferior to those of TE, and outperformed serum fibrosis indexes in identifying each stage of liver fibrosis.

Keywords: Fibrosis; Liver Biopsy; Liver Stiffness; Noninvasive Assessment.