Histopathological evaluation of liver fibrosis: quantitative image analysis vs semi-quantitative scores. Comparison with serum markers

XBP1s activates METTL3/METTL14 for ER-phagy and paclitaxel sensitivity regulation in breast cancer

Cancer cells employ the unfolded protein response (UPR) or induce autophagy, especially selective removal of certain ER domains via reticulophagy (termed ER-phagy), to mitigate endoplasmic reticulum (ER) stress for ER homeostasis when encountering microenvironmental stress. N6-methyladenosine (m6A) is one of the most abundant epitranscriptional modifications and plays important roles in various biological processes. However, the molecular mechanism of m6A modification in the ER stress response is poorly understood. In this study, we first found that ER stress could dramatically elevate m6A methylation levels through XBP1s-dependent transcriptional upregulation of METTL3/METTL14 in breast cancer (BC) cells. Further MeRIP sequencing and relevant validation results confirmed that ER stress caused m6A methylation enrichment on target genes for ER-phagy. Mechanistically, METTL3/METTL14 increased ER-phagy machinery formation by promoting m6A modification of the ER-phagy regulators CALCOCO1 and p62, thus enhancing their mRNA stability. Of note, we further confirmed that the chemotherapeutic drug paclitaxel (PTX) could induce ER stress and increase m6A methylation for ER-phagy. Furthermore, the combination of METTL3/METTL14 inhibitors with PTX demonstrated a significant synergistic therapeutic effect in both BC cells and xenograft mice. Thus, our data built a novel bridge on the crosstalk between ER stress, m6A methylation and ER-phagy. Most importantly, our work provides novel evidence of METTL3 and METTL14 as potential therapeutic targets for PTX sensitization in breast cancer.

Liver fibrosis phenotyping and severity scoring by quantitative image analysis of biopsy slides

BACKGROUND & AIMS

Digital pathology image analysis can phenotype liver fibrosis using histological traits that reflect collagen content, morphometry and architecture. Here, we aimed to calculate fibrosis severity scores to quantify these traits.

METHODS

Liver biopsy slides were categorised by Ishak stage and aetiology. We used a digital pathology technique to calculate four fibrosis severity scores: Architecture Composite Score (ACS), Collagen Composite Score (CCS), Morphometric Composite Score (MCS) and Phenotypic Fibrosis Composite Score (PH-FCS). We compared how these scores varied according to disease stage and aetiology.

RESULTS

We included 80 patients (40% female, mean age 59.0 years, mean collagen proportionate area 17.1%) with mild (F0-2, n = 28), moderate (F3-4, n = 17) or severe (F5-6, n = 35) fibrosis. All four aetiology independent scores corelated with collagen proportionate area (ACS: rp  = .512, CCS: rp  = .727, MCS: rp  = .777, PFCS: r = .772, p < .01 for all) with significant differences between moderate and severe fibrosis (p < .05). ACS increased primarily between moderate and severe fibrosis (by 95% to 226% depending on underlying aetiology), whereas MCS and CCS accumulation was more varied. We used 28 qFTs that distinguished between autoimmune- and alcohol-related liver disease to generate an MCS that significantly differed between mild and severe fibrosis for these aetiologies (p < .05).

CONCLUSIONS

We describe four aetiology-dependent and -independent severity scores that quantify fibrosis architecture, collagen content and fibre morphometry. This approach provides additional insight into how progression of architectural changes and accumulation of collagen may differ depending on underlying disease aetiology.

Association Among Cystic Volume, Intracystic Pressure, and Histopathological Changes in the Liver in Patients With Choledochal Cyst

Background Choledochal cyst is a congenital cystic dilatation of the biliary tree. Various aspects of pathophysiology are unclear, particularly with reference to intracholedochal cystic pressure (ICCP) and liver histopathology. This study aimed to determine the relationship among cystic volume, ICCP, and histopathological changes in the liver in patients with choledochal cysts. Methods This cross-sectional study was carried out among 21 patients diagnosed with choledochal cysts, who attended the Department of Pediatric Surgery at Bangabandhu Sheikh Mujib Medical University (BSMMU) from April 2021 to August 2022. Cystic volume was measured pre-operatively using ultrasonography, while ICCP was measured per-operatively with a pressure gauge. Liver histology was assessed through an intraoperative liver biopsy and graded using the meta-analysis of histological data in viral hepatitis (METAVIR) scoring system. The data were analyzed using SPSS version 25.0 (IBM Corporation, Armonk, New York). Frequency and percentages were calculated to present categorical variables, and for quantitative variables, mean, standard deviation (SD), median, and interquartile range (IQR) were calculated. Fisher's exact tests were performed to determine the association between cystic volume, ICCP, and the grading of hepatic fibrosis. A p-value of <0.05 was considered statistically significant. Results The age of the patients ranged from 1 to 12 years, with a mean of 5.0±3.4 years. The male-to-female ratio was 1:4.3. Type I cysts were the most prevalent (71.4%). The median and IQR for cystic volume were 3.4 ml and 1.1-8.2 ml, respectively. The median and IQR for ICCP were 7.46 mmHg and 4.67-9.33 mmHg, respectively. The most frequent grade of fibrosis was F1 (38.1%), followed by F2 (23.8%) and F3 (23.8%). A negative relationship between cystic volume and ICCP was observed, which was statistically significant (p=0.008). A positive relationship was also observed between ICCP and the grading of liver fibrosis, which was statistically significant (p=0.002). Although a negative correlation between cystic volume and grading of liver fibrosis was noted, it was not statistically significant (p=0.198). Conclusions This study reveals significant associations between cystic volume, ICCP, and the grading of liver fibrosis in patients with choledochal cysts. Smaller volume cysts may exhibit higher ICCP, resulting in more pronounced fibrotic changes in the liver.

SOFTWARE-ASSISTED IMAGE ANALYSIS FOR IDENTIFICATION AND QUANTIFICATION OF HEPATIC SINUSOIDAL DILATATION AND CENTRILOBULAR FIBROSIS

Background:

Heart dysfunction and liver disease often coexist because of systemic disorders. Any cause of right ventricular failure may precipitate hepatic congestion and fibrosis. Digital image technologies have been introduced to pathology diagnosis, allowing an objective quantitative assessment. The quantification of fibrous tissue in liver biopsy sections is extremely important in the classification, diagnosis and grading of chronic liver disease.

Aim:

To create a semi-automatic computerized protocol to quantify any amount of centrilobular fibrosis and sinusoidal dilatation in liver Masson’s Trichrome-stained specimen.

Method:

Once fibrosis had been established, liver samples were collected, histologically processed, stained with Masson’s trichrome, and whole-slide images were captured with an appropriated digital pathology slide scanner. After, a random selection of the regions of interest (ROI’s) was conducted. The data were subjected to software-assisted image analysis (ImageJ^®).

Results:

The analysis of 250 ROI’s allowed to empirically obtain the best application settings to identify the centrilobular fibrosis (CF) and sinusoidal lumen (SL). After the establishment of the colour threshold application settings, an in-house Macro was recorded to set the measurements (fraction area and total area) and calculate the CF and SL ratios by an automatic batch processing.

Conclusion:

Was possible to create a more detailed method that identifies and quantifies the area occupied by fibrous tissue and sinusoidal lumen in Masson’s trichrome-stained livers specimens.

Semiautomated quantification of the fibrous tissue response to complex three-dimensional filamentous scaffolds using digital image analysis

Fibrosis represents a relevant response to the implantation of biomaterials, which occurs not only at the tissue-material interface (fibrotic encapsulation) but also within the void fraction of complex three-dimensional (3D) biomaterial constructions (fibrotic ingrowth). Usual evaluation of the biocompatibility mostly depicts fibrosis at the interface of the biomaterial using semiquantitative scores. Here, the relations between encapsulation and infiltrating fibrotic growth are poorly represented. Virtual pathology and digital image analysis provide new strategies to assess fibrosis in a more differentiated way. In this study, we adopted a method previously used to quantify fibrosis in visceral organs to the quantification of fibrosis to 3D biomaterials. In a proof-of-concept study, we transferred the "Collagen Proportionate Area" (CPA) analysis from hepatology to the field of biomaterials. As one task of an experimental animal study, we used CPA analysis to quantify the fibrotic ingrowth into a filamentous scaffold after subcutaneous implantation. We were able to demonstrate that the application of the CPA analysis is well suited as an additional fibrosis evaluation strategy for new biomaterial constructions. The CPA method can contribute to a better understanding of the fibrotic interactions between 3D scaffolds and the host tissue responses.

Evolution of the liver biopsy and its future

Liver biopsies are commonly used to evaluate a wide variety of medical disorders, including neoplasms and post-transplant complications. However, its use is being impacted by improved clinical diagnosis of disorders, and non-invasive methods for evaluating liver tissue and as a result the indications of a liver biopsy have undergone major changes in the last decade. The evolution of highly effective treatments for some of the common indications for liver biopsy in the last decade (e.g., viral hepatitis B and C) has led to a decline in the number of liver biopsies in recent years. At the same time, the emergence of better technologies for histologic evaluation, tissue content analysis and genomics are among the many new and exciting developments in the field that hold great promise for the future and are going to shape the indications for a liver biopsy in the future. Recent advances in slide scanners now allow creation of "digital/virtual" slides that have image of the entire tissue section present in a slide [whole slide imaging (WSI)]. WSI can now be done very rapidly and at very high resolution, allowing its use in routine clinical practice. In addition, a variety of technologies have been developed in recent years that use different light sources and/or microscopes allowing visualization of tissues in a completely different way. One such technique that is applicable to liver specimens combines multiphoton microscopy (MPM) with advanced clearing and fluorescent stains known as Clearing Histology with MultiPhoton Microscopy (CHiMP). Although it has not yet been extensively validated, the technique has the potential to decrease inefficiency, reduce artifacts, and increase data while being readily integrable into clinical workflows. Another technology that can provide rapid and in-depth characterization of thousands of molecules in a tissue sample, including liver tissues, is matrix assisted laser desorption/ionization (MALDI) mass spectrometry. MALDI has already been applied in a clinical research setting with promising diagnostic and prognostic capabilities, as well as being able to elucidate mechanisms of liver diseases that may be targeted for the development of new therapies. The logical next step in huge data sets obtained from such advanced analysis of liver tissues is the application of machine learning (ML) algorithms and application of artificial intelligence (AI), for automated generation of diagnoses and prognoses. This review discusses the evolving role of liver biopsies in clinical practice over the decades, and describes newer technologies that are likely to have a significant impact on how they will be used in the future.

Quantitative assessment of liver fibrosis by digital image analysis reveals correlation with qualitative clinical fibrosis staging in liver transplant patients

Technologies for digitizing tissues provide important quantitative data for liver histopathology investigation. We aimed to assess liver fibrosis degree with quantitative morphometric measurements of histopathological sections utilizing digital image analysis (DIA) and to further investigate if a correlation with histopathologic scoring (Scheuer staging) exists. A retrospective study of patients with at least two post-liver transplant biopsies having a Scheuer stage of ≤ 2 at baseline were gathered. Portal tract fibrotic percentage (%) and size (μm²) were measured by DIA, while clinical fibrosis score was measured by the Scheuer system. Correlations between DIA measurements and Scheuer scores were computed by Spearman correlation analysis. Differences between mean levels of fibrosis (score, size, and percentage) at baseline versus second visit were computed by Student’s t-test. P values < 0.05 were considered significant. Of 22 patients who met the study criteria, 54 biopsies were included for analysis. Average levels ±standard error [S.E.] of portal tract fibrotic percentage (%) and size (μm²) progressed from 46.5 ± 3.6% at baseline to 61.8 ± 3.8% at the second visit (P = 0.005 by Student’s t-test), and from 28,075 ± 3,232 μm² at base line to 67,146 ± 10,639 μm² at the second visit (P = 0.002 by Student’s t-test), respectively. Average levels of Scheuer fibrosis scores progressed from 0.55±0.19 at baseline to 1.14±0.26 at the second visit (P = 0.02 by Student’s t-test). Portal tract fibrotic percentage (%) and portal tract fibrotic size were directly correlated with clinical Scheuer fibrosis stage, with Spearman correlation coefficient and P value computed as r = 0.70, P < 0.0001 and r = 0.41, P = 0.002, respectively. Digital quantitative assessment of portal triad size and fibrosis percentage demonstrates a strong correlation with visually assessed histologic stage of liver fibrosis and complements the standard assessment for allograft monitoring, suggesting the utility of future WSI analysis.

Noninvasive Tests (NITs) for Hepatic Fibrosis in Fatty Liver Syndrome

Fatty liver syndrome is an emerging health problem in the world, due to the high prevalence of obesity and alcohol use disorder. Given the nature of the disease's advancement to cirrhosis and liver-related complications, it is important to assess the severity of the disease, which is typically done via a liver biopsy. Due to the limitations and risks of liver biopsy, the role of noninvasive tests is essential and evolving to stratify the stage of the liver disease, predict the outcomes, and/or monitor the treatment response. This review is focused on noninvasive tests, including the use of serum-based biomarkers, ultrasound-based shear wave elastography, transient elastography, and magnetic resonance elastography in both clinical and research settings.

Therapeutic potential of bone marrow-derived mesenchymal stem cells and imatinib in a rat model of liver fibrosis

Considering the global increase in the prevalence of hepatic fibrosis and ineffective disease treatment, novel therapies are urgently needed. The current study is focused on comparing the therapeutic effects of mesenchymal stem cells (MSC)/imatinib combination therapy to single (MSCs or imatinib) therapy, in a rat model of carbon tetrachloride (CCL4)-induced liver fibrosis. Using rats, hepatic fibrosis was induced by injection of CCL4. Rats were divided into 5 groups: CCL4-induced hepatic fibrosis, phosphate buffered saline (PBS) treatment (vehicle control), Bone marrow-MSCs (BM_MSCs), imatinib, and bone marrow-MSCs/imatinib co-treatment. The therapeutic impact of these approaches was determined using histopathology, sirius-red staining, serum markers, and qRT-PCR for over expression of matrix components. IHC and Western blot were conducted for further confirmation of the results. Single treatment with MSCs or imatinib and the combination therapy, all significantly reduced serum levels of ALT, AST, and ALP concomitant with down-regulation of α-SMA, pro-collagen I, pro-collagen III, collagen IV, and laminin. A significant reduction of ECM components deposits and a decrease in α-SMA expression were detected in all treatment groups. Pathological observations demonstrated that 20% and 40% of the rats in the MSC and MSC/imatinib group were in grade F0 respectively, while 80% of the rats of the imatinib group were in grade 2. Even though all treatment strategies studied resulted in an equally potent reduction in the mRNA and protein expression levels of pro-fibrotic markers, in aspect of pathological observations, our results demonstrate the highest therapeutic potential of utilizing combination of BM-MSCs and imatinib.

Peritoneal Carcinomatosis Risk and Long-Term Survival Following Hepatectomy for Spontaneous Hepatocellular Carcinoma Rupture: Results of a Multicenter French Study (FRENCH-AFC)

BACKGROUND

Spontaneous rupture of hepatocellular carcinoma (HCC) remains a life-threatening complication, with a reported mortality rate of between 16 and 30% and an incidence rate of approximately 3% in Europe. Survival data and risk factors after ruptured HCC are lacking, especially for peritoneal metastasis (PM).

OBJECTIVES

The aims of this study were to evaluate the pattern of recurrence and mortality after hepatectomy for ruptured HCC, and to focus on PM.

METHODS

We retrospectively reviewed the files of patients admitted to 14 French surgical centers for spontaneous rupture of HCC between May 2000 and May 2012.

RESULTS

Overall, 135 patients were included in this study. The median disease-free survival and overall survival (OS) rates were 16.1 (11.0-21.1) and 28.7 (26.0-31.5) months, respectively, and the median follow-up period was 29 months. At last follow-up, recurrences were observed in 65.1% of patients (n = 88). The overall rate of PM following ruptured HCC was 12% (n = 16). Surgical management of PM was performed for six patients, with a median OS of 36.6 months. An α-fetoprotein level > 30 ng/mL (p = 0.0009), tumor size at rupture > 70 mm (p = 0.0009), and vascular involvement (p < 0.0001) were found to be independently associated with an increased likelihood of recurrence. No risk factor for PM was observed.

CONCLUSION

This large-cohort French study confirmed that 12% of patients had PM after ruptured HCC. A curative approach may be an option for highly selected patients with exclusive PD because of the survival benefit it could provide.

Quantification of Liver Fibrosis—A Comparative Study

Liver disease has been targeted as the fifth most common cause of death worldwide and tends to steadily rise. In the last three decades, several publications focused on the quantification of liver fibrosis by means of the estimation of the collagen proportional area (CPA) in liver biopsies obtained from digital image analysis (DIA). In this paper, early and recent studies on this topic have been reviewed according to these research aims: the datasets used for the analysis, the employed image processing techniques, the obtained results, and the derived conclusions. The purpose is to identify the major strengths and “gray-areas” in the landscape of this topic.

Hepatic Fibrosis in Dogs

Hepatic fibrosis is commonly diagnosed in dogs, often as a sequela to chronic hepatitis (CH). The development of fibrosis is a crucial event in the progression of hepatic disease that is of prognostic value. The pathophysiology of hepatic fibrosis in human patients and rodent models has been studied extensively. Although less is known about this process in dogs, evidence suggests that fibrogenic mechanisms are similar between species and that activation of hepatic stellate cells is a key step. Diagnosis and staging of hepatic fibrosis in dogs requires histopathological examination of a liver biopsy specimen. However, performing a liver biopsy is invasive and assessment of fibrotic stage is complicated by the absence of a universally accepted staging scheme in veterinary medicine. Serum biomarkers that can discriminate among different fibrosis stages are used in human patients, but such markers must be more completely evaluated in dogs before clinical use. When successful treatment of its underlying cause is feasible, reversal of hepatic fibrosis has been shown to be possible in rodent models and human patients. Reversal of fibrosis has not been well documented in dogs, but successful treatment of CH is possible. In human medicine, better understanding of the pathomechanisms of hepatic fibrosis is leading to the development of novel treatment strategies. In time, these may be applied to dogs. This article comparatively reviews the pathogenesis of hepatic fibrosis, its diagnosis, and its treatment in dogs.

An Inexpensive Digital Image Analysis Technique for Liver Fibrosis Quantification in Chronic Hepatitis B Patients

BACKGROUND AND AIM

Quantitative digital imaging analysis to evaluate liver fibrosis is accurate, but its clinical use is limited by its high cost and lack of standardization. We aimed to validate an inexpensive digital imaging analysis technique for fibrosis quantification in chronic hepatitis B patients.

MATERIAL AND METHODS

In total, 142 chronic hepatitis B patients who underwent liver biopsy and analysis of serum fibrosis markers were included. Images of Sirius red stain sections were captured and processed using Adobe Photoshop CS3 software. The percentage of fibrosis (fibrosis index) was determined by the ratio of the fibrosis area to the total sample area, expressed in pixels, and calculated automatically.

RESULTS

A strong correlation between the fibrosis index and the Ishak, Metavir, and Laennec histological staging systems were observed (r = 0.83, 0.86, and 0.84, respectively; < 0.001). The cutoff value associated with cirrhosis was 7.7% with an area under the receiver operating characteristic curve (AUROC) of 0.95 (95% confidence interval [CI], 0.92-0.99, p < 0.001). Furthermore, the fibrosis index yielded a cutoff value of 8.9% (AUROC, 0.74; 95% CI, 0.66-0.86), 12% (AUROC, 0.84; 95% CI, 0.75-0.93), and 14% (AUROC, 0.97; 95% CI, 0.92-1.0) for the diagnosis of cirrhosis 4a, 4b, and 4c, respectively. No serum markers or fibrosis models were correlated with the fibrosis index in Metavir F2-F4.

CONCLUSIONS

The present digital imaging analysis technique is reproducible and available worldwide, allowing its use in clinical practice, and can be considered as a complementary tool to traditional histological methods.

Interobserver Variability in Histologic Evaluation of Liver Fibrosis Using Categorical and Quantitative Scores

Objectives

The aim of the study was to investigate the interobserver agreement for categorical and quantitative scores of liver fibrosis.

Methods

Sixty-five consecutive biopsy specimens from patients with mixed liver disease etiologies were assessed by three pathologists using the Ishak and nonalcoholic steatohepatitis Clinical Research Network (NASH CRN) scoring systems, and the fibrosis area (collagen proportionate area [CPA]) was estimated by visual inspection (visual-CPA). A subset of 20 biopsy specimens was analyzed using digital imaging analysis (DIA) for the measurement of CPA (DIA-CPA).

Results

The bivariate weighted κ between any two pathologists ranged from 0.57 to 0.67 for Ishak staging and from 0.47 to 0.57 for the NASH CRN staging. Bland-Altman analysis showed poor agreement between all possible pathologist pairings for visual-CPA but good agreement between all pathologist pairings for DIA-CPA. There was good agreement between the two pathologists who assessed biopsy specimens by visual-CPA and DIA-CPA. The intraclass correlation coefficient, which is equivalent to the κ statistic for continuous variables, was 0.78 for visual-CPA and 0.97 for DIA-CPA.

Conclusions

These results suggest that DIA-CPA is the most robust method for assessing liver fibrosis followed by visual-CPA. Categorical scores perform less well than both the quantitative CPA scores assessed here.

A methodology for automated CPA extraction using liver biopsy image analysis and machine learning techniques

BACKGROUND AND OBJECTIVE

Collagen proportional area (CPA) extraction in liver biopsy images provides the degree of fibrosis expansion in liver tissue, which is the most characteristic histological alteration in hepatitis C virus (HCV). Assessment of the fibrotic tissue is currently based on semiquantitative staging scores such as Ishak and Metavir. Since its introduction as a fibrotic tissue assessment technique, CPA calculation based on image analysis techniques has proven to be more accurate than semiquantitative scores. However, CPA has yet to reach everyday clinical practice, since the lack of standardized and robust methods for computerized image analysis for CPA assessment have proven to be a major limitation.

METHODS

The current work introduces a three-stage fully automated methodology for CPA extraction based on machine learning techniques. Specifically, clustering algorithms have been employed for background-tissue separation, as well as for fibrosis detection in liver tissue regions, in the first and the third stage of the methodology, respectively. Due to the existence of several types of tissue regions in the image (such as blood clots, muscle tissue, structural collagen, etc.), classification algorithms have been employed to identify liver tissue regions and exclude all other non-liver tissue regions from CPA computation.

RESULTS

For the evaluation of the methodology, 79 liver biopsy images have been employed, obtaining 1.31% mean absolute CPA error, with 0.923 concordance correlation coefficient.

CONCLUSIONS

The proposed methodology is designed to (i) avoid manual threshold-based and region selection processes, widely used in similar approaches presented in the literature, and (ii) minimize CPA calculation time.

A clustering based method for collagen proportional area extraction in liver biopsy images

Collagen Proportional Area (CPA) extraction using digital image analysis (DIA) in liver biopsies provides an effective way to estimate the liver disease staging. CPA represents accurately fibrosis expansion in liver tissue. This paper presents an automated clustering-based method for fibrosis detection and CPA computation. Initially, a k-means based approach is employed to detect the liver tissue and eliminate the background. Next, the method decides about the adequacy of current biopsy, according to the size of liver tissue. Biopsies which contain small and segmented specimens must be repeated. Since the tissue has been detected, fibrosis areas are also found in the tissue. Finally, CPA is computed. For the evaluation of the proposed method 25 images are employed and the percentage errors of CPA are computed for each image. In the majority of the cases, small variation of CPA is computed, comparing to the expert's annotation.

Asian-Pacific Association for the Study of the Liver (APASL) consensus guidelines on invasive and non-invasive assessment of hepatic fibrosis: a 2016 update

Hepatic fibrosis is a common pathway leading to liver cirrhosis, which is the end result of any injury to the liver. Accurate assessment of the degree of fibrosis is important clinically, especially when treatments aimed at reversing fibrosis are being evolved. Despite the fact that liver biopsy (LB) has been considered the "gold standard" of assessment of hepatic fibrosis, LB is not favored by patients or physicians owing to its invasiveness, limitations, sampling errors, etc. Therefore, many alternative approaches to assess liver fibrosis are gaining more popularity and have assumed great importance, and many data on such approaches are being generated. The Asian Pacific Association for the Study of the Liver (APASL) set up a working party on liver fibrosis in 2007, with a mandate to develop consensus guidelines on various aspects of liver fibrosis relevant to disease patterns and clinical practice in the Asia-Pacific region. The first consensus guidelines of the APASL recommendations on hepatic fibrosis were published in 2009. Due to advances in the field, we present herein the APASL 2016 updated version on invasive and non-invasive assessment of hepatic fibrosis. The process for the development of these consensus guidelines involved review of all available published literature by a core group of experts who subsequently proposed consensus statements followed by discussion of the contentious issues and unanimous approval of the consensus statements. The Oxford System of the evidence-based approach was adopted for developing the consensus statements using the level of evidence from one (highest) to five (lowest) and grade of recommendation from A (strongest) to D (weakest). The topics covered in the guidelines include invasive methods (LB and hepatic venous pressure gradient measurements), blood tests, conventional radiological methods, elastography techniques and cost-effectiveness of hepatic fibrosis assessment methods, in addition to fibrosis assessment in special and rare situations.

Magnetic Resonance Elastography: Measurement of Hepatic Stiffness Using Different Direct Inverse Problem Reconstruction Methods in Healthy Volunteers and Patients with Liver Disease

The purpose of this study was to compare the mean hepatic stiffness values obtained by the application of two different direct inverse problem reconstruction methods to magnetic resonance elastography (MRE). Thirteen healthy men (23.2±2.1 years) and 16 patients with liver diseases (78.9±4.3 years; 12 men and 4 women) were examined for this study using a 3.0 T-MRI. The healthy volunteers underwent three consecutive scans, two 70-Hz waveform and a 50-Hz waveform scans. On the other hand, the patients with liver disease underwent scanning using the 70-Hz waveform only. The MRE data for each subject was processed twice for calculation of the mean hepatic stiffness (Pa), once using the multiscale direct inversion (MSDI) and once using the multimodel direct inversion (MMDI). There were no significant differences in the mean stiffness values among the scans obtained with two 70-Hz and different waveforms. However, the mean stiffness values obtained with the MSDI technique (with mask: 2895.3±255.8 Pa, without mask: 2940.6±265.4 Pa) were larger than those obtained with the MMDI technique (with mask: 2614.0±242.1 Pa, without mask: 2699.2±273.5 Pa). The reproducibility of measurements obtained using the two techniques was high for both the healthy volunteers [intraclass correlation coefficients (ICCs): 0.840-0.953] and the patients (ICC: 0.830-0.995). These results suggest that knowledge of the characteristics of different direct inversion algorithms is important for longitudinal liver stiffness assessments such as the comparison of different scanners and evaluation of the response to fibrosis therapy.

Shear wave elastography: An accurate technique to stage liver fibrosis in chronic liver diseases

OBJECTIVES

The goals of this study were to assess the diagnostic accuracy of shear wave elastography (SWE) using the results of histopathological analysis as a standard of reference and compare the results of SWE and those of transient elastography (TE) to the degree of fibrosis as evaluated by histomorphometry.

PATIENTS AND METHODS

Adult patients who were scheduled to undergo liver biopsy were prospectively enrolled in the study. The diagnostic performances of SWE were assessed using AUROC curve analysis according to fibrosis thresholds defined by ≥F2 (significant fibrosis), ≥F3 (advanced fibrosis) and F4 (cirrhosis). Additional analyses using the Obuchowski measures for pairwise comparisons of fibrosis stages were performed. In a subgroup of 55 patients, the relationships between stiffness as measured using SWE and TE and the percentage of fibrosis were compared using Spearman's rank coefficient.

RESULTS

Among the initially enrolled 170 patients, 148/170 (87%) had successful SWE acquisition and formed the study population. SWE sensitivity and specificity were respectively 85.1% and 82.7% (≥F2), 88.9% and 90.3% (≥F3), 93.3% and 98.3% (F4). The AUROC curves of SWE along with their 95% confidence intervals (CI) were respectively 0.904 (95%CI: 0.845-0.946) for fibrosis ≥F2; 0.958 (95%CI: 0.912-0.984) for fibrosis ≥F3 and 0.988 (95%CI: 0.955-0.999) for fibrosis=F4. The global Obuchowski measure was 0.953±0.007. In the subgroup study, a significant correlation was found between the percentage of fibrosis and stiffness as assessed by SWE (r=0.77; 95%CI: 0.63-0.86; P<0.0001) and by TE (r=0.65; 95%CI: 0.47-0.78; P<0.01).

CONCLUSION

SWE is accurate to assess liver fibrosis in patients with chronic liver disease.

Evaluation of Histological and non-Invasive Methods for the Detection of Liver Fibrosis: The Values of Histological and Digital Morphometric Analysis, Liver Stiffness Measurement and APRI Score

Prognosis and treatment of liver diseases mainly depend on the precise evaluation of the fibrosis. Comparisons were made between the results of Metavir fibrosis scores and digital morphometric analyses (DMA), liver stiffness (LS) values and aminotransferase-platelet ratio (APRI) scores, respectively. Liver biopsy specimens stained with Sirius red and analysed by morphometry, LS and APRI measurements were taken from 96 patients with chronic liver diseases (56 cases of viral hepatitis, 22 cases of autoimmune- and 18 of mixed origin). The strongest correlation was observed between Metavir score and DMA (r = 0.75 p < 0.05), followed in decreasing order by LS and Metavir (r = 0.61), LS and DMA (r = 0.47) LS and APRI (r = 0.35) and Metavir and APRI (r = 0.24), respectively. DMA is a helpful additional tool for the histopathological evaluation of fibrosis, even when the sample size is small and especially in case of advanced fibrosis. The non-invasive methods showed good correlation with the histopathological methods; LS proved to be more accurate than APRI. The stronger correlation between LS values and Metavir scores, as well as the results of DMA in case of appropriate sample size were remarkable.

Automated morphometry provides accurate and reproducible virtual staging of liver fibrosis in chronic hepatitis C

Background:

Liver fibrosis staging provides prognostic value, although hampered by observer variability. We used digital analysis to develop diagnostic morphometric scores for significant fibrosis, cirrhosis and fibrosis staging in chronic hepatitis C.

Materials and Methods:

We automated the measurement of 44 classical and new morphometric descriptors. The reference was histological METAVIR fibrosis (F) staging (F0 to F4) on liver biopsies. The derivation population included 416 patients and liver biopsies ≥20 mm-length. Two validation population included 438 patients.

Results:

In the derivation population, the area under the receiver operating characteristic (AUROC) for clinically significant fibrosis (F stage ≥2) of a logistic score combining 5 new descriptors (stellar fibrosis area, edge linearity, bridge thickness, bridge number, nodularity) was 0.957. The AUROC for cirrhosis of 6 new descriptors (edge linearity, nodularity, portal stellar fibrosis area, portal distance, granularity, fragmentation) was 0.994. Predicted METAVIR F staging combining 8 morphometric descriptors agreed well with METAVIR F staging by pathologists: κ = 0.868. Morphometric score of clinically significant fibrosis had a higher correlation with porto-septal fibrosis area (r_s = 0.835) than METAVIR F staging (r_s = 0.756, P < 0.001) and the same correlations with fibrosis biomarkers, e.g., serum hyaluronate: r_s = 0.484 versus r_s = 0.476 for METAVIR F (P = 0.862). In the validation population, the AUROCs of clinically significant fibrosis and cirrhosis scores were, respectively: 0.893 and 0.993 in 153 patients (biopsy < 20 mm); 0.955 and 0.994 in 285 patients (biopsy ≥ 20 mm). The three morphometric diagnoses agreed with consensus expert reference as well as or better than diagnoses by first-line pathologists in 285 patients, respectively: significant fibrosis: 0.733 versus 0.733 (κ), cirrhosis: 0.900 versus 0.827, METAVIR F: 0.881 versus 0.865.

Conclusion:

The new automated morphometric scores provide reproducible and accurate diagnoses of fibrosis stages via “virtual expert pathologist.”

Quantification of fibrosis by collagen proportionate area predicts hepatic decompensation in hepatitis C cirrhosis

BACKGROUND

It is unclear whether the course of cirrhosis and its prognosis are related to the amount of collagen in the liver.

AIM

To determine whether fibrosis, assessed by collagen proportionate area (CPA) in patients with compensated cirrhosis, is associated with the presence of oesophageal varices, and predict disease decompensation during the follow-up period.

METHODS

We prospectively evaluated 118 consecutive patients with compensated cirrhosis to correlate fibrosis, assessed by CPA in liver biopsies, with the presence of oesophageal varices (OV) and with the rate of liver decompensation (LD) development during a median follow-up of 72 months.

RESULTS

At baseline 38 (32.2%) patients had OV and during the follow-up (median 72 months, IQR 47-91), 17 patients (14.4%) developed LD. The mean CPA value was different in patients with and without OV (14.8 ± 5.9% vs. 21.6 ± 9.5%, P < 0.001). The best CPA cut-off for OV by area under the receiver operating characteristic (AUROC) was ≥14% and with multivariate logistic analysis CPA was the only variable associated with OV (OR: 28.32, 95% CI: 6.30-127.28; P < 0.001). By AUROC analysis the best CPA cut-off to predict LD was 18.0%. By Cox regression multivariate analysis CPA ≥18% (HR: 3.99, 95% CI: 1.04-11.45; P = 0.036), albumin (HR: 0.12, 95% CI: 0.04-0.43; P = 0.001) and presence of OV (HR: 8.15, 95% CI: 2.31-28.78; P = 0.001) were independently associated with LD.

CONCLUSION

Quantification of fibrosis by collagen proportionate area allows identification of patients with compensated HCV cirrhosis with a higher likelihood of clinically relevant portal hypertension and a higher risk of decompensation.

Non-invasive serum fibrosis markers: A study in chronic hepatitis

INTRODUCTION

Chronic hepatitis is specified as inflammatory disease of the liver lasting for more than six months. Role of noninvasive fibrosis markers as prognostication factors of the presence or absence of significant fibrosis on liver biopsy of patients with chronic hepatitis is the aim of this study.

METHODS

Two hundred twenty-one patients with chronic hepatitis involved in the study between 2011 and 2013. Routine biochemical indices and serum fibrosis markers such as aspartate aminotransferase (AST) to alanine aminotransferase (ALT) ratio (AAR), AST to platelet ratio index (APRI) and Fibrosis 4 score (FIB-4) were evaluated, and the histological grade and stage of the liver biopsy specimens were scored according to the Ishak scoring system. Diagnostic accuracies of these markers for prediction of significant fibrosis were assessed by Receiver Operating Characteristic (ROC) curve analysis.

RESULTS

Contemporaneous laboratory indices for imputing AAR, APRI, and FIB-4 were identified with liver biopsies. From all, 135 males (61.1%) and 86 females (38.9%), with mean age of 39.6±14.4 were studied. Significant correlation between stages of fibrosis and FIB-4, APRI and AAR were detected, with a correlation coefficient higher than that of other markers in the patients with Hepatitis B (r = 0.46), C (r = 0.58) and autoimmune hepatitis (r = 0.28). FIB-4 (AUROC = 0.84) and APRI (AUROC = 0.78) were superior to AAR at distinguishing severe fibrosis from mild-to-moderate fibrosis and gave the highest diagnostic accuracy.

CONCLUSION

Application of these markers was good at distinguishing significant fibrosis and decreased the need for staging liver biopsy specimens among patients with chronic hepatitis.

Liver collagen in cirrhosis correlates with portal hypertension and liver dysfunction

Liver collagen proportionate area (CPA) assessed by computer-assisted digital image analysis has been proposed as an accurate and objective histological variable for subclassifying cirrhosis. The study aimed to examine the relationship between CPA and relevant clinical parameters in cirrhotic patients and to evaluate the sampling variability for CPA. The study included 48 consecutive liver transplantation patients with established cirrhosis. Hepatic venous pressure gradient (HVPG) and serum markers of liver failure were determined prior to transplantation. CPA was assessed in the explanted livers. In 20 of the livers, CPA was measured in more than one tissue sample. CPA showed significant correlations with HVPG and with various surrogate markers of hepatic dysfunction including albumin, bilirubin, INR, MELD score and Child-Pugh score. CPA reliably discriminated HVPG ≥10 mmHg, termed 'clinically significant portal hypertension' (area under receiver operator curve: 0.923, p < 0.001; odds ratio: 1.209, p = 0.003). CPA measured on tissue blocks showed no significant sampling variability (p > 0.5). In conclusion, the study correlated portal hypertension and hepatic dysfunction with the amount of collagen in cirrhotic livers. The findings support the presumption of CPA as a useful histological marker for subclassifying cirrhosis and as a helpful supplement to the qualitative description of hepatic architectural changes in routine pathology.

Quantification of portal-bridging fibrosis area more accurately reflects fibrosis stage and liver stiffness than whole fibrosis or perisinusoidal fibrosis areas in chronic hepatitis C

Morphometry provides an objective evaluation of fibrosis in liver diseases. We developed an image analysis algorithm using automated thresholding and segmentation to separately quantify the areas and the fractal dimensions of portal-bridging fibrosis and perisinusoidal fibrosis in chronic hepatitis C liver biopsies. We studied 427 digitized liver biopsies and compared the automated measures of the different fibrosis compartments with (1) the Metavir F (fibrosis) and A (activity) histological scores, (2) the digitally assessed area of steatosis, and (3) the liver stiffness measured by elastography (Fibroscan). The perisinusoidal fibrosis area was higher than that of portal fibrosis in stages ≤F2; it reached its highest value in F2 stage and stabilized thereafter. The F3 stage was characterized by equal proportions of portal-bridging and perisinusoidal fibrosis, whereas portal-bridging area was predominant in cirrhosis. Measurement of portal-bridging fibrosis showed highly significantly different values between contiguous F stages; the ratio of portal-bridging fibrosis/perisinusoidal fibrosis displayed less overlap between Metavir stages than did the whole fibrosis area values. Fractal dimension showed that portal-bridging fibrosis tended to display a homogeneous surface-like spatial organization, whereas perisinusoidal fibrosis appeared more heterogeneous according to stage and curvilinear. The portal-bridging fibrosis area was low in cases with low Metavir activity and little steatosis, and became predominant with increasing activity and steatosis. Using stepwise multiple linear regression analysis, the liver stiffness was independently correlated to the portal-bridging fibrosis area (first step, P<0.001), the steatosis area (second step, P<0.001), and the Metavir A grade (third step, P=0.001), but not to the perisinusoidal fibrosis area. Automated quantification in a large cohort of chronic hepatitis C showed that perisinusoidal fibrosis progressively grew in early fibrosis stages but did not increase in septal or cirrhotic stages and that the portal-bridging fibrosis area appeared as a more accurate tool to assess fibrosis progression than the whole fibrosis area.

Image analysis of liver biopsy samples measures fibrosis and predicts clinical outcome

BACKGROUND & AIMS

Histopathological scoring of liver fibrosis mainly measures architectural abnormalities and requires a minimum biopsy size (⩾ 10 mm). Liver collagen quantification may allow use of small size biopsies and improve the prediction of clinical outcomes. This study evaluated the ability of the collagen proportional area (CPA) measurement to predict clinical outcomes.

METHODS

Clinical outcomes were determined using population based data-linkage for chronic hepatitis C (CHC) patients from 1992 to 2012. Quantitative digital image analysis of liver biopsies was used for CPA measurement.

RESULTS

533 patients with a biopsy size ⩾ 5 mm were included. Median follow up was 10.5 years. 26 developed hepatocellular carcinoma (HCC), 39 developed liver decompensation and 33 had liver related death. 453 had Metavir F0-F2 and 80 had F3-F4. CPA ranged from 1.3% to 44.6%. CPA and Metavir stage were independently associated with liver related death. Metavir stage, CPA stage and age were independently associated with HCC. CPA stage (C1: 0%-5%, C2: 5%-10%, C3: 10%-20%, C4: >20%) stratified risk and a significant difference in outcomes was present between all CPA stages for HCC and between C2-C3 and C3-C4 for decompensation and liver related death. The 15 year composite endpoint-free survival was 97% for C1, 89% for C2, 60% for C3, 7% for C4. C4 had significantly worse survival than ⩽ C3 (p<0.001) in cirrhotic patients.

CONCLUSIONS

CPA stage gave additional information regarding risk stratification for adverse clinical outcomes independent of Metavir stage.

An inexpensive and worldwide available digital image analysis technique for histological fibrosis quantification in chronic hepatitis C

Hepatic fibrosis staging is based on semiquantitative scores. Digital imaging analysis (DIA) appears more accurate because fibrosis is quantified in a continuous scale. However, high cost, lack of standardization and worldwide unavailability restrict its use in clinical practice. We developed an inexpensive and widely available DIA technique for fibrosis quantification in hepatitis C, and here, we evaluate its reproducibility and correlation with semiquantitative scores, and determine the fibrosis percentage associated with septal fibrosis and cirrhosis. 282 needle biopsies staged by Ishak and METAVIR scores were included. Images of trichrome-stained sections were captured and processed using Adobe(®) Photoshop(®) CS3 and Adobe(®) Bridge(®) softwares. The percentage of fibrosis (fibrosis index) was determined by the ratio between the fibrosis area and the total sample area, expressed in pixels calculated in an automated way. An excellent correlation between DIA fibrosis index and Ishak and METAVIR scores was observed (Spearman's r = 0.95 and 0.92; P < 0.001, respectively). Excellent intra-observer reproducibility was observed in a randomly chosen subset of 39 biopsies with an intraclass correlation index of 0.99 (95% CI, 0.95-0.99). The best cut-offs associated with septal fibrosis and cirrhosis were 6% (AUROC 0.97, 95% CI, 0.95-0.99) and 27% (AUROC 1.0, 95% CI, 0.99-1), respectively. This new DIA technique had high correlation with semiquantitative scores in hepatitis C. This method is reproducible, inexpensive and available worldwide allowing its use in clinical practice. The incorporation of DIA technique provides a more complete evaluation of fibrosis adding the quantification to architectural patterns.

Image analysis of liver collagen using sirius red is more accurate and correlates better with serum fibrosis markers than trichrome

BACKGROUND

Collagen proportional area (CPA) determined by quantitative digital image analysis better quantifies liver fibrosis than histological stage; however, its clinical use has been limited by non-standardized methods.

AIM

This study aimed to compare CPA obtained using different staining methods, magnifications and biopsy sizes.

METHODS

Two hundred and forty-nine patients with chronic hepatitis C who had a liver biopsy and serum fibrosis markers performed were included. CPA was measured either using a sirius red (CPAs) or a trichrome (CPAt) stain.

RESULTS

CPAs measured at 20× and 40× magnifications generated similar outcomes with interclass correlation (ICC) coefficient of 0.98. Compared with trichrome, sirius red staining had much less variation with an ICC coefficient of 0.99 for slides stained in the same batch and 0.92 in different batches. Mean CPAs was higher than mean CPAt by 3.53%, P < 0.001. Morphological analysis found that sirius red detected delicate fibrous septa and spurs better than trichrome. Both CPAs and CPAt correlated well with Metavir stage, whereas CPAs had better ability to detect cirrhosis with the area under ROC curve of 0.95. Overall CPA had superior correlation with serum markers of fibrosis in Metavir F2-F4 than that in F0-F1 and CPAs correlated better with serum fibrosis markers than CPAt in Metavir F0-F1. Multivairate analysis found that HA, α2-macroglobulin, platelet count and albumin were independently correlated with CPAs and only HA was independently correlated with CPAt.

CONCLUSIONS

Sirius red staining for CPA determination was more accurate and reliable for quantifying hepatic collagen compared with trichrome staining.

Magnetic resonance elastography in the diagnosis of hepatic fibrosis

Liver fibrosis is a common feature of many chronic liver diseases, and can ultimately progress to cirrhosis. Conventional imaging is insensitive to liver fibrosis, necessitating a liver biopsy for diagnosis and monitoring of progression. However, liver biopsy risks complications, and is an imperfect gold standard in view of sampling error and intraobserver or interobserver variation. Magnetic resonance elastography (MRE) is a noninvasive method for assessing the mechanical properties of tissues and is gaining credence as a method of assessment for hepatic fibrosis. The aim of this review is to describe how MRE is performed, to review the present literature on the subject, to compare MRE with other noninvasive techniques used to assess for liver fibrosis, and to highlight areas of future research.

Translating an understanding of the pathogenesis of hepatic fibrosis to novel therapies

The response to injury is one of wound healing and fibrogenesis, which ultimately leads to fibrosis. The fibrogenic response to injury is a generalized one across virtually all organ systems. In the liver, the injury response, typically occurring over a prolonged period of time, leads to cirrhosis (although it should be pointed out that not all patients with liver injury develop cirrhosis). The fact that many different diseases result in cirrhosis suggests a common pathogenesis. The study of hepatic fibrogenesis over the past 2 decades has been remarkably active, leading to a considerable understanding of this process. It clearly has been shown that the hepatic stellate cell is a central component in the fibrogenic process. It also has been recognized that other effector cells are important in the fibrogenic process, including resident fibroblasts, bone marrow-derived cells, fibrocytes, and even perhaps cells derived from epithelial cells (ie, through epithelial to mesenchymal transition). A key aspect of the biology of fibrogenesis is that the fibrogenic process is dynamic; thus, even advanced fibrosis (or cirrhosis) is reversible. Together, an understanding of the cellular basis for liver fibrogenesis, along with multiple aspects of the basic pathogenesis of fibrosis, have highlighted many exciting potential therapeutic opportunities. Thus, although the most effective antifibrotic therapy is simply treatment of the underlying disease, in situations in which this is not possible, specific antifibrotic therapy is likely not only to become feasible, but will soon become a reality. This review highlights the mechanisms underlying fibrogenesis that may be translated into future antifibrotic therapies and to review the current state of clinical development.

Comparative assessment of liver fibrosis by computerized morphometry in naïve patients with chronic hepatitis B and C

BACKGROUND

Liver fibrosis, now assessed by liver biopsy or using non-invasive methods, might be different in chronic hepatitis B (CHB) and chronic hepatitis C (CHC).

AIM

To compare histological amount and pattern of fibrosis in CHB and CHC.

METHODS

Sixty CHB and sixty CHC biopsies from naïve patients, standardized for the spectrum of Metavir fibrosis stages, were analysed for (1) semi-quantitative Metavir activity, steatosis, perisinusoidal fibrosis, alpha-smooth muscle actin immunoreactivity, (2) quantitative morphometry of total and perisinusoidal fibrosis ratio (FR and PFR).

RESULTS

Biopsy quality, activity, steatosis, Fibrotest(®) values were not different between the two groups. Correlation between FR and fibrosis stage was stronger in CHB (r = 0.90) than CHC (r = 0.81). Mean FR was 1.5-fold higher in CHC than CHB for early fibrosis stages (F ≤ 2, P = 0.001), with higher PFR in CHC for F0 (P = 0.001), F1 (P = 0.08) and F2 (P = 0.004). Hepatic stellate cell activation index was also higher in CHC than in CHB (P = 0.007). Diagnosis performance of FR for significant fibrosis was not statistically different in CHB than CHC (AUROC 0.92 and 0.87 respectively), but cut-offs optimizing sensitivity and specificity were higher in CHC and their extrapolation to CHB led to 10% decrease in sensitivity. In F ≤ 2 patients, correlation between FR and Fibrotest(®) was only significant in CHC.

CONCLUSIONS

As compared to CHB, amount of fibrosis is greater in CHC for F ≤ 2 patients, mainly because of higher perisinusoidal fibrosis. These data illustrate difficulty to assess early fibrosis stages by non-invasive methods, and support the need for specific cut-offs in CHB.

Transforming growth factor β neutralization ameliorates pre-existing hepatic fibrosis and reduces cholangiocarcinoma in thioacetamide-treated rats

Considerable evidence has demonstrated that transforming growth factor β (TGF-β) plays a key role in hepatic fibrosis, the final common pathway for a variety of chronic liver diseases leading to liver insufficiency. Although a few studies have reported that blocking TGF-β with soluble receptors or siRNA can prevent the progression of hepatic fibrosis, as yet no evidence has been provided that TGF-β antagonism can improve pre-existing hepatic fibrosis. The aim of this study was to examine the effects of a murine neutralizing TGF-β monoclonal antibody (1D11), in a rat model of thioacetamide (TAA)-induced hepatic fibrosis. TAA administration for 8 weeks induced extensive hepatic fibrosis, whereupon 1D11 dosing was initiated and maintained for 8 additional weeks. Comparing the extent of fibrosis at two time points, pre- and post-1D11 dosing, we observed a profound regression of tissue injury and fibrosis upon treatment, as reflected by a reduction of collagen deposition to a level significantly less than that observed before 1D11 dosing. Hepatic TGF-β1 mRNA, tissue hydroxyproline, and plasminogen activator inhibitor 1 (PAI-1) levels were significantly elevated at the end of the 8 week TAA treatment. Vehicle and antibody control groups demonstrated progressive injury through 16 weeks, whereas those animals treated for 8 weeks with 1D11 showed striking improvement in histologic and molecular endpoints. During the course of tissue injury, TAA also induced cholangiocarcinomas. At the end of study, the number and area of cholangiocarcinomas were significantly diminished in rats receiving 1D11 as compared to control groups, presumably by the marked reduction of supporting fibrosis/stroma. The present study demonstrates that 1D11 can reverse pre-existing hepatic fibrosis induced by extended dosing of TAA. The regression of fibrosis was accompanied by a marked reduction in concomitantly developed cholangiocarcinomas. These data provide evidence that therapeutic dosing of a TGF-β antagonist can diminish and potentially reverse hepatic fibrosis and also reduce the number and size of attendant cholangiocarcinomas.

Role of hyaluronic acid, its degrading enzymes, degradation products, and ferritin in the assessment of fibrosis stage in Egyptian patients with chronic hepatitis C

BACKGROUND/AIMS

Liver biopsy is considered a gold standard for fibrosis staging, but it has a high risk of morbidity. Therefore, there is an interest in developing noninvasive markers for the prediction of liver fibrosis stages.

METHODS

Hyaluronic acid, ferritin, N-acetyl-β-D-glucosaminidase, β-glucuronidase, glucosamine, aspartate transaminase, and alanine transaminase were assayed in 210 individuals with chronic hepatitis C infection. Statistical analysis was carried out by logistic regression and receiver-operating characteristic curves.

RESULTS

The best linear combination of only significant blood markers was used for the determination of the fibrosis discriminant score; score=[1.64 (numerical constant)-0.002×hyaluronic acid (pg/l)-2.68×β-glucuronidase (µmol/ml/min)-0.026×glucosamine (µg/dl)-0.001×ferritin-0.033 (ng/ml)×aspartate transaminase/alanine transaminase]. The selected fibrosis discriminant score function correctly classified 81% of patients with severe liver fibrosis at a discriminant cut-off score=0.55 (i.e. less than 0.55 indicated mild liver fibrosis and greater than 0.55 indicated severe liver fibrosis), with a sensitivity of 100% and a specificity of 73%.

CONCLUSION

A simple fibrosis index can be useful to select hepatitis C virus-infected patients with a very low risk of significant fibrosis in whom the protocol of liver biopsies may be avoided.

Novel histologic scoring system for long-term allograft fibrosis after liver transplantation in children

The existing systems for scoring fibrosis were not developed to evaluate transplanted livers. Our aim was to design and validate a novel fibrosis scoring system specifically adapted to assess liver allograft fibrosis (LAF). Clinical data, histology, transient elastography (TE) and AST/platelet ratio index (APRI) were reviewed in 38 pediatric liver transplant (LT) recipients. Protocol liver biopsies performed at 6 months and 7 years post-LT were reviewed by three pathologists who assessed LAF using the METAVIR and Ishak systems. LAF was also scored separately in portal (0-3), sinusoidal (0-3) and centrolobular areas (0-3). Scoring evaluations were correlated with fibrosis quantification using morphometry, and also with TE and APRI. Statistical correlations between morphometry and METAVIR were 0.571 (p < 0.000) and 0.566 (p < 0.000) for the Ishak system. The novel score (0-9) for separate assessment of portal, sinusoidal and centrolobular fibrosis showed a better correlation with morphometry (0.731; p < 0.000) and high intra-/interobserver agreement (0.966; p < 0.000 and 0.794; p < 0.000, respectively). No correlation was found between TE or APRI and morphometry or the three histologic scores. In conclusion, this novel semiquantitative fibrosis scoring system seems to more accurately reflect LAF than the existing scoring system and may become a practical tool for staging fibrosis in LT.

Effect of prolyl hydroxylase domain-2 haplodeficiency on the hepatocarcinogenesis in mice

BACKGROUND & AIMS

The two major primary liver cancers in adults are hepatocellular carcinoma and cholangiocarcinoma. These tumors rapidly outgrow their vascular supply and become hypoxic, resulting in the production of hypoxia inducible factors. Recently, interest has grown in the regulators of these factors. Several reports have been published describing the role of prolyl hydroxylase domains--the key oxygen sensor responsible for the degradation of hypoxia inducible factors--tumor progression and vascularisation. The effect of prolyl hydroxylase domain 2 on the pathogenesis of liver cancer has never been studied.

METHODS

A diethylnitrosamine-induced mouse model was used in this study, allowing primary hepatic tumors to occur as a result of chronic liver damage. Several parameters of prolyl hydroxylase domain 2-haplodeficient mice were compared to those of wild type mice, thereby focussing on the expression of angiogenic factors and on the hepatic progenitor cell activation and differentiation.

RESULTS

This study shows that inhibiting prolyl hydroxylase domain 2 increases the hepatocarcinogenesis and stimulates the development of cholangiocarcinoma. Furthermore, PHD2 deficiency and the accompanying continuous HIF activation, selected for a more metastatic tumor phenotype.

CONCLUSIONS

The effect of prolyl hydroxylase domain 2 deficiency on hepatocarcinogenesis hold a great potential for therapeutic intervention, since hypoxia and the selection for a more aggressive cholangiocarcinoma phenotype might also have a repercussion on patients receiving long-term treatment with anti-angiogenic compounds.

Fibrosis distribution in explanted cirrhotic livers

AIMS

Little information is available regarding the distribution of fibrosis within cirrhotic livers. We measured collagen in cirrhotic explants to determine if fibrosis differs (i) between left (L) and right (R) lobes, and (ii) between different aetiologies.

METHODS AND RESULTS

Ten cases each of common aetiologies of cirrhosis were studied: alcoholic liver disease (ALD), primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC), autoimmune hepatitis (AIH), hepatitis C virus (HCV) and hepatitis B virus (HBV). A total of 120 tissue blocks (one block each from L and R lobes) were studied. Collagen was measured as collagen proportionate area (CPA), i.e. the proportion of the tissue sections stained by picro-Sirius red. L and R lobes contained similar amounts of fibrosis (r = 0.788; P < 0.0001) with good agreement between L and R lobes (Bland-Altman analysis, R lobe bias = 1.35%). Median CPA across all aetiologies (R plus L lobes) was 21.5%, (L = 8-40%, R = 10-47%). There was more fibrosis in ALD (30%, 15-47%) than PBC (23.5%, 16-34%) and PSC (22.5%, 8-33%), which in turn showed more than AIH (18.5%, 10-40%), HCV (17%, 13-31%) and HBV (16.5%, 8-30%).

CONCLUSIONS

At the time of transplantation cirrhotic livers have different ranges of collagen proportionate area, according to aetiology. R lobe fibrosis corresponds with L lobe fibrosis. The range of fibrosis within each aetiological group could be useful for prognostic subclassification.

Fibrosis progression under maintenance interferon in hepatitis C is better detected by blood test than liver morphometry

We evaluated whether quantitative measurements of liver fibrosis with recently developed diagnostics outperform histological staging in detecting natural or interferon-induced changes. We compared Metavir staging, morphometry (area and fractal dimension) and six blood tests in 157 patients with chronic hepatitis C from two trials testing maintenance interferon for 96 weeks. Paired liver biopsies and blood tests were available for 101 patients, and there was a significant improvement in Metavir activity and a significant increase in blood tests reflecting fibrosis quantity in patients treated with interferon when compared with controls - all per cent changes in histological fibrosis measures were significantly increased in F1 vs F2-4 stages only in the interferon group. For the whole population studied between weeks 0 and 96, there was significant progression only in the area of fibrosis (AOF) (P = 0.026), FibroMeter (P = 0.020) and CirrhoMeter (P = 0.003). With regards to dynamic reproducibility, agreement was good (r(ic) ≥ 0.72) only for Metavir fibrosis score, FibroMeter and CirrhoMeter. The per cent change in AOF was significantly higher than that of fractal dimension (P = 0.003) or Metavir fibrosis score (P = 0.015). CirrhoMeter was the only blood test with a change significantly higher than that of AOF (P = 0.039). AOF and two blood tests, reflecting fibrosis quantity, have high sensitivity and/or reproducibility permitting the detection of a small progression in liver fibrosis over two years. A blood test reflecting fibrosis quantity is more sensitive and reproducible than morphometry. The study also shows that maintenance interferon does not improve fibrosis, whatever its stage.

THE ULTRASONIC THREE-DIMENSIONAL FILTER FOR THE QUANTITATIVE DIAGNOSIS OF LIVER FIBROSIS

At present, percutaneous liver biopsy is the gold standard in assessing liver fibrosis such as hepatitis and cirrhosis, but there could be sampling error, and specimens might not represent the state of the whole liver accurately because only about 0.002% of the organ is sampled. In this research, we propose the three-dimensional fiber structure extraction echo filter to realize a quantitative ultrasonic diagnosis. The filter is designed based on a statistical theory, and it is possible to reduce the noise contained in a back scattered ultrasonic echo signal, and to visualize the structure of a fiber.

Steatosis degree, measured by morphometry, is linked to other liver lesions and metabolic syndrome components in patients with NAFLD

BACKGROUND AND AIM

We carried out morphometric measurements of steatosis to evaluate relationships between steatosis degree and other liver lesions or metabolic syndrome components in nonalcoholic fatty liver disease (NAFLD).

PATIENTS AND METHODS

We developed an algorithm to measure steatosis area. Two hundred and fourteen patients with NAFLD were included in derivation (10) and validation (204) groups. Controls consisted of patients who were steatosis-free (12), patients with chronic hepatitis C (188), and patients with alcoholic chronic liver disease (94).

RESULTS

Accuracy of steatosis area was considered as good or very good in at least 72% of cases by three pathologists. Steatosis areas were as follows: NAFLD = 10.3 ± 9.7%, virus = 2.4 ± 3.1%, alcohol = 7.8 ± 8.2% (P<0.0001). Steatosis area was closely related to steatosis grades in NAFLD (P<0.0001 for linear trend). Steatosis area increased from the fibrosis stage F0 to the fibrosis state F2, then decreased in the stages F3 and F4 (cirrhosis) (P<0.0001 for quadratic trend). Fibrosis was present in an average steatosis area of approximately 4% (defining significant steatosis) and in nonalcoholic steatohepatitis by approximately 8% (defining severe steatosis). Steatosis and fibrosis area increased symmetrically until approximately 10%, then steatosis area decreased to null as average fibrosis area reached 32%. Average fasting glycemia (approximately 92 mg/dl) or triglycerides and BMI plateaued before a steatosis area of approximately 4%, then increased thereafter. Significant steatosis was present in 61.3% of NAFLD versus 20.2% of viral hepatitis (P<0.0001) and in 58.7% of alcoholic liver diseases (P=0.674).

CONCLUSIONS

The average threshold of steatosis area is 4% for the development of fibrosis or metabolic syndrome components and 8% for nonalcoholic steatohepatitis. Steatosis area may contribute to defining the normal range and clinical course of metabolic components.

Non-invasive markers for hepatic fibrosis

With great advancements in the therapeutic modalities used for the treatment of chronic liver diseases, the accurate assessment of liver fibrosis is a vital need for successful individualized management of disease activity in patients. The lack of accurate, reproducible and easily applied methods for fibrosis assessment has been the major limitation in both the clinical management and for research in liver diseases. However, the problem of the development of biomarkers capable of non-invasive staging of fibrosis in the liver is difficult due to the fact that the process of fibrogenesis is a component of the normal healing response to injury, invasion by pathogens, and many other etiologic factors. Current non-invasive methods range from serum biomarker assays to advanced imaging techniques such as transient elastography and magnetic resonance imaging (MRI). Among non-invasive methods that gain strongest clinical foothold are FibroScan elastometry and serum-based APRI and FibroTest. There are many other tests that are not yet widely validated, but are none the less, promising. The rate of adoption of non-invasive diagnostic tests for liver fibrosis differs from country to country, but remains limited. At the present time, use of non-invasive procedures could be recommended as pre-screening that may allow physicians to narrow down the patients' population before definitive testing of liver fibrosis by biopsy of the liver. This review provides a systematic overview of these techniques, as well as both direct and indirect biomarkers based approaches used to stage fibrosis and covers recent developments in this rapidly advancing area.

Application of the HALF index obviates the need for liver biopsy in half of all patients with chronic hepatitis B

BACKGROUND AND AIMS

Transient elastography (TE) is useful for predicting the fibrosis stage, but it is unsatisfactory as a substitute for liver biopsy, especially in patients with chronic hepatitis B (CHB). This study was performed to establish a reliable model for predicting significant fibrosis (SF) in patients with CHB.

METHODS

All CHB patients who were admitted to undergo liver biopsy were enrolled. They were randomly classified into either a training set (n = 139) or a validation set (n = 69). A model for predicting SF was established in the training set and validated in the validation set. Low and high cutoff values (COVs) were chosen for sensitivity ≥ 99% and specificity ≥ 99%, respectively.

RESULTS

A total of 208 patients were enrolled. Age was 39 ± 12 years and 149 (71.6%) were men. In the training set, liver stiffness values and serum haptoglobin, apolipoprotein A1, and α2-macroglobulin levels were independent predictors of SF on multivariate analysis. These variables were used to construct a novel model, called the HALF index. The area under the receiver operating characteristics curve of the HALF index for predicting SF was significantly higher than that of TE alone (0.915 vs 0.877, P = 0.010). Using low and high COVs of the HALF index, it appears that approximately half (47.1%) of patients could avoid liver biopsy, with an associated accuracy of 99.0%.

CONCLUSION

A combination of liver stiffness and serum markers identified SF with a high degree of accuracy. Approximately half of all patients with CHB could avoid liver biopsy through the utilization of the HALF index.

Soy isoflavone delays the progression of thioacetamide-induced liver fibrosis in rats

OBJECTIVE

Our aim was to investigate the effect of soy isoflavone (SI) on liver fibrosis in a thioacetamide (TAA)-induced rat model.

MATERIALS AND METHODS

Twenty-eight rats were assigned to four groups: sham group, fibrosis group, low-dose treatment group (LDg) and high-dose treatment group (HDg). SI (90 or 270 mg/kg) was administered daily during the model development by TAA. Standard liver tests, platelet derived growth factor-BB (PDGF-BB) and tissue inhibitor of metalloproteinase-1 (TIMP-1) were measured. The expression of collagen, α-smooth muscle actin (α-SMA) and transforming growth factor-β1 (TGF-β1) in liver tissue was determined. Electron microscopy was used to perform ultrastructural analysis of the livers.

RESULTS

Hepatic fibrosis was induced by 8 weeks of TAA administration. However, following the administration of SI, collagen staining significantly declined as compared with the fibrosis group (p < 0.01). Less collagen fibers around the hepatic stellate cells (HSCs) were observed in HDg as compared to the fibrosis group and LDg. There was no significant difference in standard liver tests between the fibrosis group and the two treatment groups. The levels of PDGF-BB and TIMP-1 in the two SI-treated groups were significantly lower than in the fibrosis group (p < 0.01). The expression of α-SMA and TGF-β1 in HDg was less than that in the fibrosis group and LDg (p < 0.01).

CONCLUSION

Administration of a high dose of SI resulted in an obvious inhibitory effect on liver fibrosis induced by TAA in rats. One hypothesis is that the effect may be related to the inhibition of HSC activation and proliferation.

Non-invasive assessment of liver fibrosis in chronic hepatitis C

Quantification of hepatic fibrosis is of critical importance in chronic hepatitis C not only for prognosis, but also for antiviral treatment indication. Two end points are clinically relevant: detection of significant fibrosis (indication for antiviral treatment) and detection of cirrhosis (screening for eosphageal varices and hepatocellular carcinoma). Until recently, liver biopsy was considered the reference method for the evaluation of liver fibrosis. Limitations of liver biopsy (invasiveness, sampling error, and inter-observer variability) have led to the development of non-invasive methods. Currently available methods rely on two different approaches: a "biological" approach based on the dosage of serum fibrosis biomarkers; and a "physical" approach based on the measurement of liver stiffness, using transient elastography (TE). This review is aimed at discussing the advantages and limits of non-invasive methods and liver biopsy and the perspectives for their rational use in clinical practice in the management of patients with chronic hepatitis C.

The relationship between liver disease stage and liver fibrosis: a tangled web

The structural consequences of chronic liver disease are described as a series of liver disease 'stages' with scarring and architectural change that eventually destroys and replaces the normal lobular structure of the liver. Fibrosis ('excess collagen') and stage have been confused in histological staging systems. Fibrosis is part of increasing liver disease stage, but fibrosis and stage are different. Staging liver disease is important in routine histopathological assessment. Measurement of liver fibrosis is another process. The collagenous proportion of a liver biopsy [collagen proportionate area (CPA)] correlates with hepatic venous pressure gradient (HVPG), which is of recognized prognostic value. CPA at 1 year post-transplantation in hepatitis C virus-infected patients predicts subsequent clinical decompensation. CPA in cirrhotic patients predicts decompensation more accurately than staging or HVPG. The 'cirrhosis' stage category has poor prognostic power, and CPA effectively substages cirrhosis. CPA improves the description of liver disease stage. Proper validation of antifibrotic treatments and 'non-invasive markers of liver fibrosis' requires measurement of liver fibrosis (and not liver biopsy stage scores). It is unacceptable for the words 'fibrosis' and 'score' to remain next to each other. There are benefits to properly understanding liver fibrosis and liver disease stage and properly assessing each of them.