ACG clinical guideline: the diagnosis and management of focal liver lesions

Significance of hepatocyte atypia in liver fine needle aspiration

Fine needle aspiration (FNA) of the liver is frequently the diagnostic procedure of choice for sampling hepatic lesions. One of the main diagnostic challenges in the interpretation of liver FNA is distinguishing dysplastic lesions and well-differentiated hepatocellular carcinoma (WD-HCC) from benign processes, as they share significant cytomorphologic overlap. Furthermore, the diagnosis of HCC often requires evaluation of stroma for invasion, which may not be present on cytology and small needle biopsy specimens. A reporting system for liver cytopathology has yet to be instituted. Without standardized and well-defined criteria for hepatocyte atypia, we recommend limiting the use of atypia in evaluation of liver FNA specimens to describe a diagnosis of exclusion, in which all known benign and neoplastic processes have been ruled out. The cytologic findings on the FNA of a liver nodule may be best reported as atypical hepatocytes in the absence of a core needle biopsy or cell block sufficient to render a definitive diagnosis of HCC.

Scoping review of clinical practice guidelines on the management of benign liver tumours

Objective

Benign liver tumours (BLT) are increasingly diagnosed as incidentalomas. Clinical implications and management vary across and within the different types of BLT. High-quality clinical practice guidelines are needed, because of the many nuances in tumour types, diagnostic modalities, and conservative and invasive management strategies. Yet, available observational evidence is subject to interpretation which may lead to practice variation. Therefore, we aimed to systematically search for available clinical practice guidelines on BLT, to critically appraise them, and to compare management recommendations.

Design

A scoping review was performed within MEDLINE, EMBASE, and Web of Science. All BLT guidelines published in peer-reviewed, and English language journals were eligible for inclusion. Clinical practice guidelines on BLT were analysed, compared, and critically appraised using the Appraisal of Guidelines, Research and Evaluation (AGREE II) checklist regarding hepatic haemangioma, focal nodular hyperplasia (FNH), and hepatocellular adenoma (HCA). Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations (PRISMA) for scoping reviews were adhered to.

Results

The literature search yielded unique 367 papers, 348 were excluded after screening of title/abstract, and 16 after full-text screening. Three guidelines were included: the American College of Gastroenterology (ACG; 2014), Brazilian Society of Hepatology (SBH; 2015), and European Association for the Study of the Liver (EASL; 2016). There was no uniformity in the assessment methods for grading and gravity of recommendations between guidelines. Among observed differences were: (1) indications for biopsy in all three tumours; (2) advices on contraceptive pills and follow-up in FNH and HCA; (3) use of an individualised approach to HCA; (4) absence of recommendations for treatment of HCA in men; and (5) approaches to HCA subtype identification on magnetic resonance imaging.

Conclusion

Recognising differences in recommendations can assist in harmonisation of practice standards and identify unmet needs in research. This may ultimately contribute to improved global patient care.

Behavior and complications of hepatocellular adenoma during pregnancy and puerperium: a retrospective study and systematic review

BACKGROUND

Hepatocellular adenomas (HCA) are benign liver tumors at risk of hemorrhage. The influence of pregnancy on HCA growth and potential bleeding remains unclear. This study investigates HCA-associated behavior and bleeding complications during or shortly after pregnancy.

METHODS

(I) Single center retrospective cohort study of HCA during and after pregnancy (II) Systematic literature review.

RESULTS

The retrospective study included 11 patients, of which 4 with HCA ≥5 cm. In only two patients HCA showed growth during pregnancy. In this local cohort, no HCA-related hemorrhages occurred during median follow-up of 34 months (interquartile range 19-58 months). The systematic review yielded 33 studies, totaling 90 patients with 99 pregnancies. Of 73 pregnancies without prior HCA-related intervention, 39 HCA remained stable (53.4%), 11 regressed (15.1%), and 23 (31.5%) progressed. Fifteen HCA-related hemorrhages occurred in HCA measuring 6.5-17.0 cm. Eight patients experienced bleeding during pregnancy, two during labor and five postpartum.

CONCLUSION

Although hemorrhage of HCA during or shortly after pregnancy is rare and only reported in HCA ≥6.5 cm, it can be fatal. Pregnancy in women with HCA, regardless of size, warrant a close surveillance strategy. Observational studies on behavior and management of HCA ≥5 cm during and immediately after pregnancy are needed.

Assessment of task-based image quality for abdominal CT protocols linked with national diagnostic reference levels

Objectives

To assess task-based image quality for two abdominal protocols on various CT scanners. To establish a relationship between diagnostic reference levels (DRLs) and task-based image quality.

Methods

A protocol for the detection of focal liver lesions was used to scan an anthropomorphic abdominal phantom containing 8- and 5-mm low-contrast (20 HU) spheres at five CTDI_vol levels (4, 8, 12, 16, and 20 mGy) on 12 CTs. Another phantom with high-contrast calcium targets (200 HU) was scanned at 2, 4, 6, 10, and 15 mGy using a renal stones protocol on the same CTs. To assess the detectability, a channelized Hotelling observer was used for low-contrast targets and a non-prewhitening observer with an eye filter was used for high contrast targets. The area under the ROC curve and signal to noise ratio were used as figures of merit.

Results

For the detection of 8-mm spheres, the image quality reached a high level (mean AUC over all CTs higher than 0.95) at 11 mGy. For the detection of 5-mm spheres, the AUC never reached a high level of image quality. Variability between CTs was found, especially at low dose levels. For the search of renal stones, the AUC was nearly maximal even for the lowest dose level.

Conclusions

Comparable task-based image quality cannot be reached at the same dose level on all CT scanners. This variability implies the need for scanner-specific dose optimization.

Key Points

• There is an image quality variability for subtle low-contrast lesion detection in the clinically used dose range.

• Diagnostic reference levels were linked with task-based image quality metrics.

• There is a need for specific dose optimization for each CT scanner and clinical protocol.

Liver and Biliary Disease of Pregnancy and Anesthetic Implications: A Review

Liver and biliary disease complicates pregnancy in varying degrees of severity to the mother and fetus, and anesthesiologists may be asked to assist in caring for these patients before, during, and after birth of the fetus. Therefore, it is important to be familiar with how different liver diseases impact the pregnancy state. In addition, knowing symptoms, signs, and laboratory markers in the context of a pregnant patient will lead to faster diagnosis and treatment of such patients. This review article discusses changes in physiology of parturients, patients with liver disease, and parturients with liver disease. Next, general treatment of parturients with acute and chronic liver dysfunction is presented. The article progresses to specific liver diseases with treatments as they relate to pregnancy. And finally, important aspects to consider when anesthetizing parturients with liver disease are discussed.

Does Argininosuccinate Synthase 1 (ASS1) Immunohistochemistry Predict an Increased Risk of Hemorrhage for Hepatocellular Adenomas?

Hepatocellular adenomas (HCAs) often pursue an innocuous clinical course. Recent work has elucidated important subtypes of HCA and biomarkers to identify them, including HCA at an increased risk for malignant transformation. Another key complication of HCAs is the risk of spontaneous tumoral hemorrhage, which may be life-threatening. Identification of a predictive biomarker for this clinical complication would therefore be of clinical value. It has been suggested that Argininosuccinate Synthase 1 (ASS1) immunohistochemistry (IHC) identifies HCA with a high propensity for hemorrhage. The aim of our study was to validate ASS1 IHC as a predictive marker of hemorrhage. Eighty-nine HCAs were collected for ASS1 IHC and subtyped according to published criteria. Clinical records were examined for evidence of tumoral hemorrhage. Twenty-one (23.6%) HCAs were complicated by clinically detected hemorrhage and were more likely to be resected (P=0.0002). Hemorrhage complicated all WHO subtypes of HCA. There was no association between hemorrhage and HCA subtype (P=0.92). Neither the distribution of ASS1 expression nor the intensity of ASS1 expression compared to normal liver showed a significant association with hemorrhage (P=0.051 and 0.34). Interlaboratory comparison of 8 cases showed good agreement regarding the intensity (6/8 and 7/8) and distribution of staining (7/8 and 7/8) across 3 laboratories performing ASS1 IHC. In conclusion, all subtypes of HCA may be complicated by hemorrhage. ASS1 IHC expression did not correlate with hemorrhagic complications. Caution is prudent before routine implementation of ASS1 IHC in clinical practice.

Differentiation of Hepatocellular Carcinoma from Hepatic Hemangioma and Focal Nodular Hyperplasia using Computed Tomographic Spectral Imaging

BACKGROUND AND AIMS

Hepatocellular carcinoma (HCC) is the most common primary hepatic malignancy. This study was designed to investigate the value of computed tomography (CT) spectral imaging in differentiating HCC from hepatic hemangioma (HH) and focal nodular hyperplasia (FNH).

METHODS

This was a retrospective study of 51 patients who underwent spectral multiple-phase CT at 40-140 keV during the arterial phase (AP) and portal venous phase (PP). Slopes of the spectral curves, iodine density, water density derived from iodine- and water-based material decomposition images, iodine uptake ratio (IUR), normalized iodine concentration, and the ratio of iodine concentration in liver lesions between AP and PP were measured or calculated.

RESULTS

As energy level decreased, the CT values of HCC (n=31), HH (n=17), and FNH (n=7) increased in both AP and PP. There were significant differences in IUR in the AP, IUR in the PP, normalized iodine concentration in the AP, slope in the AP, and slope in the PP among HCC, HH, and FNH. The CT values in AP, IUR in the AP and PP, normalized iodine concentration in the AP, slope in the AP and PP had high sensitivity and specificity in differentiating HH and HCC from FNH. Quantitative CT spectral data had higher sensitivity and specificity than conventional qualitative CT image analysis during the combined phases.

CONCLUSIONS

Mean CT values at low energy (40-90 keV) and quantitative analysis of CT spectral data (IUR in the AP) could be helpful in the differentiation of HCC, HH, and FNH.

An MR-based radiomics model for differentiation between hepatocellular carcinoma and focal nodular hyperplasia in non-cirrhotic liver

Purpose

We aimed to develop and validate a radiomics model for differentiating hepatocellular carcinoma (HCC) from focal nodular hyperplasia (FNH) in non-cirrhotic livers using Gd-DTPA contrast-enhanced magnetic resonance imaging (MRI).

Methods

We retrospectively enrolled 149 HCC and 75 FNH patients treated between May 2015 and May 2019 at our center. Patients were randomly allocated to a training (n=156) and validation set (n=68). In total, 2260 radiomics features were extracted from the arterial phase and portal venous phase of Gd-DTPA contrast-enhanced MRI. Using Max-Relevance and Min-Redundancy, random forest, least absolute shrinkage, and selection operator algorithm for dimensionality reduction, multivariable logistic regression was used to build the radiomics model. A clinical model and combined model were also established. The diagnostic performance of the models was compared.

Results

Eight radiomics features were chosen for the radiomics model, and four clinical factors (age, sex, HbsAg, and enhancement pattern) were chosen for the clinical model. A combined model was built using the factors from the previous models. The classification accuracy of the combined model differentiated HCC from FNH in both the training and validation sets (0.956 and 0.941, respectively). The area under the receiver operating characteristic curve of the combined model was significantly better than that of the clinical model for both the training (0.984 vs. 0.937, p=0.002) and validation (0.972 vs. 0.903, p=0.032) sets.

Conclusions

The combined model provided a non-invasive quantitative method for differentiating HCC from FNH in non-cirrhotic liver with high accuracy. Our model may assist clinicians in the clinical decision-making process.

Diagnostic accuracy of apparent diffusion coefficient (ADC) value in differentiating malignant from benign solid liver lesions: a systematic review and meta-analysis

OBJECTIVES

We undertook a systematic review and meta-analysis of the diagnostic performance of mean apparent diffusion coefficient (ADC) values derived by diffusion-weighted (DW)-MRI in the characterization of solid benign and malignant liver lesions, and to assess their value in discriminating these lesions in daily routine practice.

METHODS

A systematic review of PubMed, Embase, Scopus, and Web of Science was conducted to retrieve studies that used ADC values for differentiating solid benign/dysplastic nodules and malignant liver lesions. A bivariate random-effects model with pooled sensitivity and specificity values with 95% CI (confidence interval) was used. This meta-analysis was performed on the per-lesion basis. Summary receiver operating characteristic (SROC) plot and area under curve (AUC) were created.

RESULTS

A total of 14 original articles were retrieved. The combined (95% CI) sensitivity and specificity of mean ADC values for differentiating solid benign from malignant lesions were 78% (67-86%) and 74% (64-81%), respectively. The pooled (95% CI) positive and negative LRs were respectively 3 (2.3-3.8) and 0.3 (0.21-0.43). The DOR (95% CI) was 10 (7-15). The AUC (95% CI) of the SROC plot was 82% (78-85%). Reporting bias was negligible (p value of regression test = 0.36). Mean size of malignant lesions and breathing pattern of MRI were found to be sources of heterogeneity of pooled sensitivity.

CONCLUSION

ADC measurement independently may not be an optimal diagnostic imaging method for differentiating solid malignant from solid benign hepatic lesions. The meta-analysis showed that ADC measurement had moderate diagnostic accuracy for characterizing solid liver lesions. Further prospective and comparative studies with pre-specified ADC thresholds could be performed to investigate the best MRI protocol and ADC threshold for characterizing solid liver lesions.

ADVANCES IN KNOWLEDGE

ADC measurement by DW-MRI does not have a good diagnostic performance to differentiate solid malignant from solid benign lesions. Therefore, we suggest not using ADC values in clinical practice to evaluate solid liver lesions.

Focal nodular hyperplasia mimicking hepatocellular adenoma and carcinoma in two cases

Focal nodular hyperplasia (FNH) is a solid benign tumor of the liver, predominantly in young women. A correct diagnosis of FNH is essential for making appropriate clinical decisions and avoiding unnecessary liver resection. Herein, we reported that two male cases with FNH, who initially presented with persistent abdominal discomfort, were misdiagnosed with hepatocellular adenoma (HCA) and hepatocellular carcinoma (HCC) on contrast-enhanced magnetic resonance imaging and computed tomography scans, respectively. After surgery, a histological diagnosis of FNH was finally established. In this paper, we also reviewed the knowledge regarding diagnosis and differential diagnosis of FNH on imaging examinations, which are helpful for avoiding misdiagnoses and guiding clinical interventions.

A Multicenter, 10-Year Experience With Hepatocellular Adenoma: Risk Factors and Disease Course

BACKGROUND

Management of hepatocellular adenoma (HA) is marked by a paucity of recent studies. Long-term follow-up data from an equal access health care system may facilitate our understanding of the natural disease course of HA and identify modifiable risk factors.

METHODS

A multi-institutional, retrospective review of patients with HA from 2008-2017 was performed. Patient demographics, disease characteristics, and clinical outcomes were analyzed.

RESULTS

Of 124 patients identified, 94% were women with a mean age at diagnosis of 39.5 years (range 20-82). Median follow-up was 22.5 months (range 0-114) with thirty-four (27.4%) patients eventually undergoing hepatectomy. Mean BMI of the study population was 30.5 kg/m² (range 16-72). Stratified by size, average BMI for adenomas ≥5 cm was 34 kg/m² compared to 28 kg/m² for those <5 cm (P < .05). The predominant symptom at presentation was abdominal pain (41.1%), while just 4% presented with acute rupture. Overall incidence of the malignancy was 2.5%. Among all patients, oral contraceptive use was documented in 74 (59.7%) patients, of whom 36 (29.0%) discontinued OC for at least six months. Regression after OC cessation occurred in seven patients (19.4%) while the majority (77.8%) remained stable.

DISCUSSION

This decade-long review analyzing the impact of modifiable risk factors identifies a direct correlation between BMI and hepatocellular adenoma size. Rupture and malignant transformation are rare entities. Cessation of OC appears to be an effective strategy in the management of hepatic adenoma. Further investigations are warranted to determine if addressing modifiable risk factors such as BMI might induce further HA regression.

A Case of Hepatic Cyst-Induced Internal Jugular Venous Thrombosis

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Echocardiography can demonstrate hepatic cyst–induced right atrial compression.

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Hepatic cyst–induced blood flow stasis can cause internal jugular venous thrombus.

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Laparoscopic deroofing of hepatic cysts is a safe and effective treatment.

[State of the art in the diagnostics of hepatocellular carcinoma and current treatment options]

Hepatocellular carcinoma (HCC) is the most frequent primary hepatic malignancy and arises most often based on liver cirrhosis. Of the HCC 80-85% demonstrate a typical contrast medium behavior in imaging, characterized by arterial hypervascularization followed by wash-out in the portal or late venous phase. This specific contrast behavior is diagnostic for HCC in patients at risk. The use of liver-specific contrast agents increases the sensitivity for diagnosis of HCC and can facilitate the differentiation from other liver lesions. At initial diagnosis approximately 50% of HCC are solitary, 40% multifocal and 10% diffuse. Depending on the tumor extent and stage, therapeutic options in patients with HCC include local treatment (resection, ablation, radiation, liver transplantation), locoregional measures (transarterial chemoembolization, selective internal radiotherapy) or systemic therapy (including immunotherapy), either as a stand-alone procedure or in various combinations.

Diagnostic Accuracy of Delayed Phase Post Contrast Computed Tomographic Images in the Diagnosis of Focal Liver Lesions in Dogs: 69 Cases

To describe the computed tomographic (CT) features of focal liver lesions (FLLs) in dogs, that could enable predicting lesion histotype. Dogs diagnosed with FLLs through both CT and cytopathology and/or histopathology were retrospectively collected. Ten qualitative and 6 quantitative CT features have been described for each case. Lastly, a machine learning-based decision tree was developed to predict the lesion histotype. Four categories of FLLs - hepatocellular carcinoma (HCC, n = 13), nodular hyperplasia (NH, n = 19), other benign lesions (OBL, n = 18), and other malignant lesions (OML, n = 19) - were evaluated in 69 dogs. Five of the observed qualitative CT features resulted to be statistically significant in the distinction between the 4 categories: surface, appearance, lymph-node appearance, capsule formation, and homogeneity of contrast medium distribution. Three of the observed quantitative CT features were significantly different between the 4 categories: the Hounsfield Units (HU) of the radiologically normal liver parenchyma during the pre-contrast scan, the maximum dimension, and the ellipsoid volume of the lesion. Using the machine learning-based decision tree, it was possible to correctly classify NHs, OBLs, HCCs, and OMLs with an accuracy of 0.74, 0.88, 0.87, and 0.75, respectively. The developed decision tree could be an easy-to-use tool to predict the histotype of different FLLs in dogs. Cytology and histology are necessary to obtain the final diagnosis of the lesions.

Is This Patient's Liver Mass Cancer?

Undiagnosed liver lesions are important findings that can affect the physical and mental well-being of patients. They are usually incidental findings identified while clinicians are performing other imaging tests. It is important for clinicians and patients to identify the causative factors for these lesions in order to further reduce risk, develop treatment plans, and produce better outcomes. Both men and women can develop liver lesions, which may require surgical intervention. Knowing the key risk factors for common lesions can help clinicians confidently diagnose patients without costly workup.

Deep learning for differentiation of benign and malignant solid liver lesions on ultrasonography

PURPOSE

The ability to reliably distinguish benign from malignant solid liver lesions on ultrasonography can increase access, decrease costs, and help to better triage patients for biopsy. In this study, we used deep learning to differentiate benign from malignant focal solid liver lesions based on their ultrasound appearance.

METHODS

Among the 596 patients who met the inclusion criteria, there were 911 images of individual liver lesions, of which 535 were malignant and 376 were benign. Our training set contained 660 lesions augmented dynamically during training for a total of 330,000 images; our test set contained 79 images. A neural network with ResNet50 architecture was fine-tuned using pre-trained weights on ImageNet. Non-cystic liver lesions with definite diagnosis by histopathology or MRI were included. Accuracy of the final model was compared with expert interpretation. Two separate datasets were used in training and evaluation, one with all lesions and one with lesions deemed to be of uncertain diagnosis based on the Code Abdomen rating system.

RESULTS

Our model trained on the complete set of all lesions achieved a test accuracy of 0.84 (95% CI 0.74-0.90) compared to expert 1 with a test accuracy of 0.80 (95% CI 0.70-0.87) and expert 2 with a test accuracy of 0.73 (95% CI 0.63-0.82). Our model trained on the uncertain set of lesions achieved a test accuracy of 0.79 (95% CI 0.69-0.87) compared to expert 1 with a test accuracy of 0.70 (95% CI 0.59-0.78) and expert 2 with a test accuracy of 0.66 (95% CI 0.55-0.75). On the uncertain dataset, compared to all experts averaged, the model had higher test accuracy (0.79 vs. 0.68, p = 0.025).

CONCLUSION

Deep learning algorithms proposed in the current study improve differentiation of benign from malignant ultrasound-captured solid liver lesions and perform comparably to expert radiologists. Deep learning tools can potentially be used to improve the accuracy and efficiency of clinical workflows.

Deletion of Sox9 in the liver leads to hepatic cystogenesis in mice by transcriptionally downregulating Sec63

Hepatic cysts are found in heterogeneous disorders with different pathogeneses, of which simple hepatic cysts and polycystic liver diseases are two major types. The process of hepatic cytogenesis for these two diseases is caused by defects in remodelling of the ductal plate during biliary tract development, which is called ductal plate malformation. SOX9 is a transcription factor participating in the process of bile duct development, and thus, its dysregulation may play important roles in hepatic cystogenesis. SEC63 encodes an endoplasmic reticulum membrane protein that is mutated in human autosomal dominant polycystic liver disease. However, the transcriptional regulation of SEC63 is largely unknown. In the present study, a liver-specific Sox9 knockout (Sox9^LKO ) mouse was generated to investigate the roles and underlying mechanism of SOX9 in hepatic cystogenesis. We found that hepatic cysts began to be observed in Sox9^LKO mice at 6 months of age. The number and size of cysts increased with age in Sox9^LKO mice. In addition, the characteristics of hepatic cytogenesis, including the activation of proliferation, absence of primary cilium, and disorder of polarity in biliary epithelial cells, were detected in the livers of Sox9^LKO mice. RNAi silencing of SOX9 in human intrahepatic biliary epithelial cells (HIBEpic) resulted in increased proliferation and reduced formation of the primary cilium. Moreover, Sec63 was downregulated in primary biliary epithelial cells from Sox9^LKO mice and SEC63 in HIBEpic transfected with siSOX9. Chromatin immunoprecipitation assays and luciferase reporter assays further demonstrated that SOX9 transcriptionally regulated the expression of SEC63 in biliary epithelial cells. Importantly, the overexpression of SEC63 in HIBEpic partially reversed the effects of SOX9 depletion on the formation of primary cilia and cell proliferation. These findings highlight the biological significance of SOX9 in hepatic cytogenesis and elucidate a novel molecular mechanism underlying hepatic cytogenesis. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Systematic review on percutaneous aspiration and sclerotherapy versus surgery in symptomatic simple hepatic cysts

BACKGROUND

Simple hepatic cysts (SHC) may cause pain and bloating and thus impair quality of life. Whereas current guidelines recommend laparoscopic cyst deroofing, percutaneous aspiration and sclerotherapy (PAS) may be used as a less invasive alternative. This review aimed to assess the efficacy of PAS and surgical management in patients with symptomatic SHC.

METHODS

A systematic search in PubMed and Embase was performed according to PRISMA-guidelines. Studies reporting symptoms were included. Methodological quality was assessed by the MINORS-tool. Primary outcomes were symptom relief, symptomatic recurrence and quality of life, for which a meta-analysis of proportions was performed.

RESULTS

In total, 736 patients from 34 studies were included of whom 265 (36%) underwent PAS, 348 (47%) laparoscopic cyst deroofing, and 123 (17%) open surgical management. During weighted mean follow-up of 26.1, 38.2 and 21.3 months, symptoms persisted in 3.5%, 2.1%, 4.2%, for PAS, laparoscopic and open surgical management, respectively. Major complication rates were 0.8%, 1.7%, and 2.4% and cyst recurrence rates were 0.0%, 5.6%, and 7.7%, respectively.

CONCLUSION

Outcomes of PAS for symptomatic SHC appear to be excellent. Studies including a step-up approach which reserves laparoscopic cyst deroofing for symptomatic recurrence after one or two PAS procedures are needed.

Imaging-based diagnosis of benign lesions and pseudolesions in the cirrhotic liver

Liver cirrhosis is a leading cause of death worldwide, with 1-year mortality rates of up to 57% in decompensated patients. Hepatocellular carcinoma (HCC) is the most common primary tumor in cirrhotic livers and the second leading cause of cancer-related mortality worldwide. Annually, up to 8% of patients with cirrhosis develop HCC. The diagnosis of HCC rarely requires histological confirmation: in fact, according to the most recent guidelines, the imaging features of HCC are almost always sufficient for a certain diagnosis. Thus, the role of the radiologist is pivotal because the accurate detection and characterization of focal liver lesions in patients with cirrhosis are essential in improving clinical outcomes. Despite recent technical innovations in liver imaging, several issues remain for radiologists regarding the differentiation of HCC from other hepatic lesions, particularly benign lesions and pseudolesions. It is important to avoid misdiagnosis of benign liver lesions as HCC (false-positive cases) because this diagnostic misinterpretation may lead to ineligibility of a patient for potentially curative treatments or inappropriate assignment of high priority scores to patients on waiting lists for liver transplantation. This review presents a pocket guide that could be useful for the radiologist in the diagnosis of benign lesions and pseudolesions in cirrhotic livers, highlighting the imaging features that help in making the correct diagnosis of macroregenerative nodules; siderotic nodules; arterioportal shunts; hemangiomas, including fast-filling hemangiomas, hemangiomas with pseudowashout, and sclerosed hemangiomas; confluent fibrosis; pseudomasses in chronic portal vein thrombosis; and focal fatty changes.

Giant Cavernous Hemangioma of the Liver in a Patient with Autosomal Dominant Polycystic Kidney Disease

Patient: Male, 41-year-old

Final Diagnosis: Autosomal dominant polycystic kidney disease

Symptoms: Pain

Medication: —

Clinical Procedure: Computed tomography • ultrasonography

Specialty: Gastroenterology and Hepatology • Medicine, General and Internal • Nephrology

Diagnosis of Focal Nodular Hyperplasia (FNH) after Liver Transplantation

Following liver transplantation (LT), recipients can develop benign and malignant hepatic masses just like any other patient. Patients transplanted for hepatocellular carcinoma (HCC) undergo surveillance imaging, and any new mass seen on imaging must be carefully evaluated to rule out recurrent cancer. Focal nodular hyperplasia (FNH) is a benign tumor of the liver that most often occurs in women and is rarely symptomatic. It is important to distinguish FNH from more serious etiologies, such as recurrent HCC and other malignancies, since the treatments differ greatly. To date, there have been very few reports of FNH occurring in a liver allograft. We present a case of a patient with a history of a carcinoid tumor who underwent LT for HCC. Several years posttransplant, the patient was found to have a liver mass with classic features of HCC on imaging. The liver biopsy revealed the unexpected diagnosis of FNH. This finding avoided unnecessary treatment for HCC, which is associated with morbidity, especially in the posttransplant setting. We present our diagnostic approach, discuss the clinicopathologic and imaging findings of FNH, and review the literature on FNH in the posttransplant setting.

Continued value of the serum alpha-fetoprotein test in surveilling at-risk populations for hepatocellular carcinoma

BACKGROUNDS AND AIMS

Because of the known limitations of ultrasonography (US) alone, we re-evaluated whether complimentary testing for serum alpha-fetoprotein (AFP) is helpful in surveilling for hepatocellular carcinoma (HCC) in high-risk populations.

METHODS

We included, from a hospital-based cancer registry, 1,776 asymptomatic adults who were surveilled biannually with the AFP test and US and eventually diagnosed with HCC between 2007 and 2015. Based on the screening results, these patients were divided into three groups: AFP (positive for AFP only; n = 298 [16.8%]), US (positive for US only; n = 978 [55.0%]), and AFP+US (positive for both; n = 500 [28.2%]). We compared the outcomes of the three groups, calculating the survival of the AFP group both as observed survival and as survival corrected for lead-time.

RESULTS

In terms of tumor-related factors, the separate AFP and US groups were more likely to have early stage HCC and to receive curative treatments than the combined AFP+US group (Ps<0.05). The AFP group had significantly better overall and cancer-specific survival than the AFP+US group after adjusting for covariates (adjusted hazard ratios [HRs] 0.68 and 0.62, respectively). In analyses correcting for lead-time in the AFP group (doubling time 120 days), the respective adjusted HRs for the AFP group were unchanged (0.74 and 0.67), but they were no longer significant after additional adjustment for tumor stage and curative treatment (0.87 and 0.81).

CONCLUSIONS

HCC cases detected by the AFP test without abnormal ultrasonic findings appear to have better survival, possibly as a result of stage migration and the resulting cures. Complementary AFP surveillance, together with US, could be helpful for at-risk patients.

Benign Liver Tumors

Background

Due to the frequent use of medical imaging including ultrasonography, the incidence of benign liver tumors has increased. There is a large variety of different solid benign liver tumors, of which hemangioma, focal nodular hyperplasia (FNH), and hepatocellular adenoma (HCA) are the most frequent. Advanced imaging techniques allow precise diagnosis in most of the patients, which reduces the need for biopsies only to limited cases. Patients with benign liver tumors are mostly asymptomatic and do not need any kind of treatment. Symptoms can be abdominal pain and pressure effects on adjacent structures. The 2 most serious complications are bleeding and malignant transformation.

Summary

This review focuses on hepatic hemangioma (HH), FNH, and HCA, and provides an overview on clinical presentations, surgical and interventional treatment, as well as conservative management. Treatment options for HHs, if indicated, include liver resection, radiofrequency ablation, and transarterial catheter embolization, and should be carefully weighed against possible complications. FNH is the most frequent benign liver tumor without any risk of malignant transformation, and treatment should only be restricted to symptomatic patients. HCA is associated with the use of oral contraceptives or other steroid medications. Unlike other benign liver tumors, HCA may be complicated by malignant transformation. HCAs have been divided into 6 subtypes based on molecular and pathological features with different risk of complication.

Key Message

The vast majority of benign liver tumors remain asymptomatic, do not increase in size, and rarely need treatment. Biopsies are usually not needed as accurate diagnosis can be obtained using modern imaging techniques.

Hepatocellular carcinoma in adult thalassemia patients: an expert opinion based on current evidence

Beta-thalassemia represents a heterogeneous group of haemoglobin inherited disorders, among the most common genetic diseases in the world, frequent in the Mediterranean basin. As beta-thalassemia patients' survival has increased over time, previously unknown complications are observed with increasing frequency. Among them, an increased risk of hepatocellular carcinoma (HCC) has been registered. Our aim is to reduce inequalities in diagnosis and treatment and to offer patients univocal recommendations in any institution.The members of the panel - gastroenterologists, radiologists, surgeons and oncologists -were selected on the basis of their publication records and expertise. Thirteen clinical questions, derived from clinical needs, and an integration of all the committee members' suggestions, were formulated. Modified Delphi approach involving a detailed literature review and the collective judgement of experts, was applied to this work.Thirteen statements were derived from expert opinions' based on the current literature, on recently developed reviews and on technological advancements. Each statement is discussed in a short paragraph reporting the current key evidence. As this is an emerging issue, the number of papers on HCC in beta-thalassemia patients is limited and based on anecdotal cases rather than on randomized controlled studies. Therefore, the panel has discussed, step by step, the possible differences between beta-thalassemia and non beta-thalassemia patients. Despite the paucity of the literature, practical and concise statements were generated.This paper offers a practical guide organized by statements describing how to manage HCC in patients with beta-thalassemia.

Hepatic Hydatid Cyst Misdiagnosed as Simple Cyst: A Case Report

BACKGROUND Hepatic hydatid cysts is a cystic disease of the liver caused by echinococcosis. Echinococcosis usually forms a monolocular cyst and causes space occupying effect, while alveolar echinococcosis often progresses into a polycystic mass that dilates into the adjacent liver parenchyma, with different clinical manifestations. In clinical practice, hepatic hydatid cyst and simple cyst are generally diagnosed clearly, but there are still misdiagnosed cases. CASE REPORT A 40-year-old female patient with no symptoms had a computed tomography and magnetic resonance imaging examination that revealed multiple round-like shadows of varying sizes in her liver. Combined with the laboratory and imaging results, the diagnosis was considered as hepatic hemangioma and hepatic cyst. Therefore, we planned to perform ultrasound guided microwave ablation of hepatic hemangioma and laparoscopic fenestration of hepatic cyst. Considering the possibility of hepatic hydatid cysts during the operation, partial hepatectomy was performed. CONCLUSIONS More attention should be paid to the differential diagnosis of cystic space occupying lesions in the liver. For the treatment of hepatic cyst, if suspected, must change the surgical strategy.

Focal Nodular Hyperplasia and Hepatic Adenoma: Evaluation and Management

Focal nodular hyperplasia and hepatocellular adenoma are benign liver lesions that occur most frequently in women and may be found as incidental findings on imaging. hepatocellular adenomas may be infrequently associated with malignant progression or risk of rupture and as such, require surveillance or definitive treatments based on their size threshold. It is important clinically to differentiate these lesions, and utilizing imaging modalities such as contrast enhanced ultrasound or magnetic resonance imaging can be helpful in diagnosis. Further molecular subtyping of hepatocellular adenoma lesions may be beneficial to describe risk factors and potential future clinical complications.

Optimization of FireNet for Liver Lesion Classification

In recent years, deep learning techniques, and in particular convolutional neural networks (CNNs) methods have demonstrated a superior performance in image classification and visual object recognition. In this work, we propose a classification of four types of liver lesions, namely, hepatocellular carcinoma, metastases, hemangiomas, and healthy tissues using convolutional neural networks with a succinct model called FireNet. We improved speed for quick classification and decreased the model size and the number of parameters by using fire modules from SqueezeNet. We have used bypass connection by adding it around Fire modules for learning a residual function between input and output, and to solve the vanishing gradient problem. We have proposed a new Particle Swarm Optimization (NPSO) to optimize the network parameters in order to further boost the performance of the proposed FireNet. The experimental results show that the parameters of FireNet are 9.5 times smaller than GoogLeNet, 51.6 times smaller than AlexNet, and 75.8 smaller than ResNet. The size of FireNet is reduced 16.6 times smaller than GoogLeNet, 75 times smaller than AlexNet and 76.6 times smaller than ResNet. The final accuracy of our proposed FireNet model was 89.2%.

Elastography for characterization of focal liver lesions: current evidence and future perspectives

Focal liver lesions (FLLs) are a common finding during routine abdominal ultrasound (US). The differential diagnosis between diverse types of FLLs, especially between benign and malignant ones, is extremely important and can often be particularly challenging. Radiological techniques with contrast administration and/or liver biopsy are mostly necessary for establishing diagnosis, but they have several contraindications or complications. Due to limitations of these tools, there is urgent and still unmet need to develop a first line, non-invasive and simple method to diagnose FLLs. Elastography is an US-based imaging modality that provides information about the physical parameter corresponding to the tissue stiffness and can be considered a virtual biopsy. Several elastographic approaches have been developed, such as transient elastography, strain imaging and share wave imaging, which include point shear wave elastography and 2D shear wave elastography. These tools are already in use for evaluating liver fibrosis and in the assessment of focal lesions in other organs, like breast and thyroid gland. This review aims to assess the current evidence of different techniques based on elastography in the setting of FLLs, in order to evaluate accuracy, limitations and future perspectives. In particular, we focused on two contexts: the ability of discriminating between benign and malignant lesions, especially hepatocellular carcinoma and liver metastasis, and the surveillance after percutaneous therapy. This could have a high clinical impact making elastography crucial to identify the appropriate management of FLLs.

New insights in the management of Hepatocellular Adenoma

Hepatocellular adenoma (HCA) are benign liver tumours that may be complicated by haemorrhage or malignant transformation to hepatocellular carcinoma. Epidemiological data are fairly outdated, but it is likely to assume that the incidence has increased over the past decades as HCA are more often incidentally found due to the more widespread use of imaging techniques and the increased incidence of obesity. Various molecular subgroups have been described. Each of these molecular subgroups are defined by specific gene mutations and pathway activations. Additionally, they are all related to specific risk factors and show a various biological behaviour. These molecular subgroups may be identified using immunohistochemistry and molecular characterization. Contrast-enhanced MRI is the recommended imaging modality to analyse patients with suspected hepatocellular adenoma allowing to determine the subtype in up to 80%. Surgical resection remains to be the golden standard in treating HCA, although resection is deemed unnecessary in a large number of cases, as studies have shown that the majority of HCA will regress over time without complications such as haemorrhage or malignant transformation occurring. It is preferable to treat patients with suspected HCA in high volume centres with combined expertise of liver surgeons, hepatologists, radiologists and (molecular) pathologists.

Extracapsular Hepatocellular Adenoma: A Diagnostic Dilemma

Hepatocellular adenoma (HCA) is a benign neoplasm of the hepatic parenchyma. The use of oral contraceptives (OCP) in women is the most well-established risk for the development of HCA. HCA commonly presents as an intracapsular mass of the liver but there are very few cases of extracapsular HCA. This is a case of a middle-aged female who presented to the emergency department with left shoulder pain and epigastric tenderness on physical exam. Subsequent imaging of the abdomen revealed a mass arising from the anterior wall of the stomach, with evidence of surrounding hemorrhage. The patient underwent exploratory laparotomy that revealed free blood in the peritoneum and a hemorrhagic mass arising from the stomach wall. The mass was successfully removed with no postoperative complications. Histopathological examination of the mass was consistent with an infarcted inflammatory HCA. This case illustrates this unusual presentation of a rare diagnosis.

Optimizing small liver biopsy specimens: a combined cytopathology and surgical pathology perspective

Both fine-needle aspiration (FNA) and core needle biopsy (CNB) are widely used to obtain liver biopsy specimens, particularly from mass lesions. However, the advantages and disadvantages of FNA versus CNB in terms of appropriate use, diagnostic yield, complications, and whether or not specimens should be handled by cytopathologists, surgical pathologists, or both remain subjects of controversy. This review addresses the issues of sample adequacy, appropriate use of each technique and complications, and challenges regarding the diagnosis of both hepatic tumors and non-neoplastic liver disease.

Benign Hepatic Tumors: From Incidental Imaging Finding to Clinical Management

Benign hepatic tumors (BHTs) are commonly detected as incidental finding mainly due to the frequent utilization of imaging modalities, including ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI). Rigorous clinical evaluation, with a particular focus on chronic liver disease (CLD) or risk factors for CLD, medication history, physical examination for signs of CLD, blood tests, and a review of past liver radiology constitute the initial steps in the evaluation of a new liver lesion. Further, contrast-enhanced imaging using US, CT and MRI, can be used depending on the clinical scenario and their availability. The contrast-enhanced MRI provides detailed tissue assessment while avoiding exposure to radiations, although it is scarcely available and expensive. While the liver tissue-specific protocols ensure precise diagnosis, a biopsy is recommended in selected or doubtful cases. Further, most BHTs, such as hemangiomas, are harmless and do not require special management or follow-up, the hepatic adenomas and large or atypical cases of focal nodular hyperplasia are clinically relevant and require management/follow-up. In such cases, it is favorable to have a multidisciplinary team approach, which includes hepatologist, radiologist, hepatobiliary surgeon, and pathologist. This review aims to elaborate the current understanding of BHTs, and provide a practical guidance for primary care and practitioners of family and internal medicine for the disease evaluation and management.

Improving B-mode ultrasound diagnostic performance for focal liver lesions using deep learning: A multicentre study

Background

The diagnosis performance of B-mode ultrasound (US) for focal liver lesions (FLLs) is relatively limited. We aimed to develop a deep convolutional neural network of US (DCNN-US) for aiding radiologists in classification of malignant from benign FLLs.

Materials and methods

This study was conducted in 13 hospitals and finally 2143 patients with 24,343 US images were enrolled. Patients who had non-cystic FLLs with pathological results were enrolled. The FLLs from 11 hospitals were randomly divided into training and internal validations (IV) cohorts with a 4:1 ratio for developing and evaluating DCNN-US. Diagnostic performance of the model was verified using external validation (EV) cohort from another two hospitals. The diagnosis value of DCNN-US was compared with that of contrast enhanced computed tomography (CT)/magnetic resonance image (MRI) and 236 radiologists, respectively.

Findings

The AUC of Model^LBC for FLLs was 0.924 (95% CI: 0.889–0.959) in the EV cohort. The diagnostic sensitivity and specificity of Model^LBC were superior to 15-year skilled radiologists (86.5% vs 76.1%, p = 0.0084 and 85.5% vs 76.9%, p = 0.0051, respectively). Accuracy of Model^LBC was comparable to that of contrast enhanced CT (both 84.7%) but inferior to contrast enhanced MRI (87.9%) for lesions detected by US.

Interpretation

DCNN-US with high sensitivity and specificity in diagnosing FLLs shows its potential to assist less-experienced radiologists in improving their performance and lowering their dependence on sectional imaging in liver cancer diagnosis.

Contrast imaging techniques to diagnose hepatocellular carcinoma in cirrhotics outside regular surveillance

INTRODUCTION AND AIM

The American Association for the Study of the Liver (AASLD) recommends contrast computerized tomography (CT-scan) and magnetic resonance (MRI) to diagnose hepatocellular carcinoma (HCC) arising in cirrhotic patients under semiannual surveillance with abdominal ultrasound (US). A US guided fine needle biopsy (FNB) serves the same purpose in radiologically undiagnosed tumors and incidentally detected nodules in cirrhotics outside surveillance. In this population, we evaluated the performance of radiological diagnosis of HCC according to 2010 AASLD recommendations.

MATERIALS AND METHODS

All cirrhotic patients with a liver nodule incidentally detected by US were prospectively investigated with a sequential application of CT-scan/MRI examination and a FNB.

RESULTS

Between 2011 and 2015, 94 patients (mean age 67 years) had a liver nodule (total 120) detected by US in the context of histologically confirmed cirrhosis. Mean nodules diameter was 40 (10-160) mm, 87 (73%) <5cm. At histology, 84 (70%) nodules were HCC, 8 (7%) intrahepatic cholangiocarcinoma, 6 (5%) metastases, 2 (2%) neuroendocrine tumors and 20 (16%) benign lesions. Hyperenhancement in arterial phase followed by wash-out in venous phases on at least one radiological technique was demonstrated in 62 nodules (61 HCC, 1 high grade dysplastic nodule), with a specificity of 97% (IC95%: 85-100%), sensitivity 73% (IC95%: 62-81%) and diagnostic accuracy 80%, being 64% for ≥5cm HCC. Sensitivity of AFP >200ng/mL was 12% (IC95%: 6-23%).

CONCLUSION

A single contrast imaging technique showing a typical contrast pattern confidently identifies HCC also in cirrhotic patients with an incidental liver nodule, thereby reducing the need for FNB examinations.

Relationship between platelet-based models and the prognosis of patients with malignant hepatic tumors

Platelets (PLTs) are involved in tumor growth, metabolism and vascular activation. PLT-based models have been reported to have significant value on the recurrence of malignant hepatic tumors. The present study aimed to investigate the effect of PLT count and 18 PLT-based models on the prognosis of patients with malignant hepatic tumors. The clinical data from 189 patients with malignant hepatic tumors were retrospectively analyzed and used to calculate the scores of the 18 PLT-based models. Receiver operating characteristic curve was used to determine the suitable cut-off values of mortality and recurrence in patients with malignant hepatic tumors. The overall survival and cumulative recurrence rates of patients were calculated using Kaplan-Meier survival curves and the difference was analyzed using log-rank test. Multivariate analysis was performed to determine the independent risk factors of recurrence-free survival and overall survival. In the present study, 11 models were considered as predictors of mortality (P<0.05) and six models were considered as predictors of recurrence (P<0.05). The results from multivariate analysis demonstrated that vascular cancer embolus, uric acid >231 µmol/l, hemoglobin >144 g/l and the Lok index model >0.695 were considered as independent risk factors of mortality (P<0.05). Furthermore, vascular cancer embolus, PLT to lymphocyte ratio (PLR) >175 and fibrosis-4 (FIB-4) >4.82 were independent factors of recurrence (P<0.05). In addition, the results from this study indicated that the Lok-index could be considered as a predictor of the overall survival rate. In conclusion, the FIB-4 and PLR model may be valuable for predicting the recurrence-free rate of patients with malignant hepatic tumors.

Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy Tourniquet as a Resource for Hepatic Transplant in Patient With Hepatic Adenomatosis: A Case Report

BACKGROUND

Hepatic adenomatosis is defined as the presence of more than 10 adenomatous lesions seated on a healthy liver. The most frequent complication is bleeding, presenting a risk of malignant neoplasms of less than 10%.

CLINICAL CASE

We present a case of a 28-year-old woman with polycystic ovary syndrome treated with oral contraceptives for 10 years. Ultrasonography showed benign mass, and biopsy specimen showed adenoma. Nuclear magnetic resonance showed multiple hepatic adenomatosis with a large nodule in the right hepatic lobe of 21 cm and another 10 nodules in segments II, III, IVa, IVb, VIII-VII, and VI. A computed tomography scan with volumetry was performed where a future liver remnant volume (FLRV) of 30% was observed with an FLRV body weight ratio of 0.34%. Surgery was planned in 2 stages. First, the lesions of sections II-III, IVa, and IVb were resected and a ligature of right port vein and a tourniquet in Cantlie line were performed. At 15 days the computed tomography volumetry reported an FLRV of 48% with an FLRV body weight ratio of 0.55%. The second time was completed with a regulated right hepatectomy. The hospital stay was 5 days the first time and 6 days the second time, without complications. At present, the patient follows revisions in consultation without pathologic findings of interest.

CONCLUSION

In some extreme cases, surgical resection is limited by the FLRV and the risk of liver failure. Before considering liver transplant, associating liver partition and portal vein ligation for staged hepatectomy may be an effective alternative in the management of these patients.

Large size and haemorrhage are not contraindications to laparoscopic resection of hepatocellular adenoma

BACKGROUND

Hepatocellular adenoma (HCA) is a hepatocyte derived neoplastic lesion with an increasing incidence and a strong association with oestrogen therapy. Laparoscopic resection has proven safe for small, non-ruptured lesions whilst its use for large adenomas (≥10 cm) and cases of haemorrhage requires further investigation.

METHODS

All patients undergoing liver resection for HCA at the Royal Brisbane Hospital between January 2003 and April 2018 were analysed. Ethics approval was obtained.

RESULTS

Thirty-three laparoscopic and three open resections were performed in 35 patients, all female, with a median age of 35 years (range 14-75). Nine laparoscopic resections were performed for large adenomas (≥10 cm) and 17 laparoscopic resections were performed for adenomas of intermediate size (5-9.9 cm). Only one conversion to open surgery was required for an intermediate sized tumour. Haemorrhage, either intratumoural, intraparenchymal or free intraperitoneal was the indication for resection in six of the 33 laparoscopic cases. Median operative time was 143 and 266 min for laparoscopically resected intermediate and large lesions, respectively. The median length of stay was 5 days (range 4-9) and no major complications were observed in the laparoscopic group. β-catenin mutation was seen in four of nine large adenomas whereas the inflammatory subtype constituted 11 of 17 intermediate sized lesions.

CONCLUSION

Laparoscopic surgery has been demonstrated to be safe for the resection of HCA in this group of patients. Importantly, haemorrhage and/or large size were not barriers to laparoscopic resection.

Hepatic hemangioma: What internists need to know

Hepatic hemangioma (HH) is the most common benign liver tumor and it is usually found incidentally during radiological studies. This tumor arises from a vascular malformation; however, the pathophysiology has not been clearly elucidated. Symptoms usually correlate with the size and location of the tumor. Less commonly the presence of a large HH may cause life-threatening conditions. The diagnosis can be established by the identification of HH hallmarks in several imaging studies. In patients that present with abdominal symptoms other etiologies should be excluded first before attributing HH as the cause. In asymptomatic patient’s treatment is not required and follow up is usually reserved for HH of more than 5 cm. Symptomatic patients can be managed surgically or with other non-surgical modalities such as transcatheter arterial embolization or radiofrequency ablation. Enucleation surgery has shown to have fewer complications as compared to hepatectomy or other surgical techniques. Progression of the tumor is seen in less than 40%. Hormone stimulation may play a role in HH growth; however, there are no contraindications for hormonal therapy in patients with HH due to the lack of concrete evidence. When clinicians encounter this condition, they should discern between observation and surgical or non-surgical management based on the clinical presentation.

Noninvasive Detection of Extracellular pH in Human Benign and Malignant Liver Tumors Using CEST MRI

PURPOSE

In this study, we aimed to use 3T magnetic resonance imaging (MRI), which is clinically available, to determine the extracellular pH (pHe) of liver tumors and prospectively evaluate the ability of chemical exchange saturation transfer (CEST) MRI to distinguish between benign and malignant liver tumors.

METHODS

Different radiofrequency irradiation schemes were assessed for ioversol-based pH measurements at 3T. CEST effects were quantified in vitro using the asymmetric magnetization transfer ratio (MTRasym) at 4.3 ppm from the corrected Z spectrum. Generalized ratiometric analysis was conducted by rationing resolved ioversol CEST effects at 4.3 ppm at a flip angle of 60 and 350°. Fifteen patients recently diagnosed with hepatic carcinoma and five patients diagnosed with hepatic hemangioma [1 male; mean age, 48.6 (range, 37-59) years] were assessed.

RESULTS

By conducting dual-power CEST MRI, the pH of solutions was determined to be 6.0-7.2 at 3T in vitro. In vivo, ioversol signal intensities in the tumor region showed that the extracellular pH in hepatic carcinoma was acidic(mean ± standard deviation, 6.66 ± 0.19), whereas the extracellular pH was more physiologically neutral in hemangioma (mean ± standard deviation, 7.34 ± 0.09).The lesion size was similar between CEST pH MRI and T2-weighted imaging.

CONCLUSION

dual-power CEST MRI can detect extracellular pH in human liver tumors and can provide molecular-level diagnostic tools for differentiating benign and malignant liver tumors at 3T.

HCC screening: assessment of an abbreviated non-contrast MRI protocol

BACKGROUND

Hepatocellular carcinoma (HCC) guidelines recommend ultrasound screening in high-risk patients. However, in some patients, ultrasound image quality is suboptimal due to factors such as hepatic steatosis, cirrhosis, and confounding lesions. Our aim was to investigate an abbreviated non-contrast magnetic resonance imaging (aNC-MRI) protocol as a potential alternative screening method.

METHODS

A retrospective study was performed using consecutive liver MRI studies performed over 3 years, with set exclusion criteria. The unenhanced T2-weighted, T1-weighted Dixon, and diffusion-weighted sequences were extracted from MRI studies with a known diagnosis. Each anonymised aNC-MRI study was read by three radiologists who stratified each study into either return to 6 monthly screening or investigate with a full contrast-enhanced MRI study.

RESULTS

A total of 188 patients were assessed; 28 of them had 42 malignant lesions, classified as Liver Imaging Reporting and Data System 4, 5, or M. On a per-patient basis, aNC-MRI had a negative predictive value (NPV) of 97% (95% confidence interval [CI] 95-98%), not significantly different in patients with steatosis (99%, 95% CI 93-100%) and no steatosis (97%, 95% CI 94-98%). Per-patient sensitivity and specificity were 85% (95% CI 75-91%) and 93% (95% CI 90-95%).

CONCLUSION

Our aNC-MRI HCC screening protocol demonstrated high specificity (93%) and NPV (97%), with a sensitivity (85%) comparable to that of ultrasound and gadoxetic acid contrast-enhanced MRI. This screening method was robust to hepatic steatosis and may be considered an alternative in the case of suboptimal ultrasound image quality.

A rare case of hepatocellular carcinoma arising from gadoxetate-retaining hepatic adenoma

Hepatocellular adenomas (HCAs) are benign lesions of the liver which can rarely undergo malignant transformation. We report a 26-year-old woman with no underlying liver disease found to have an incidental liver lesion on noncontrast CT during workup for gastric reflux. Follow up MRI revealed a 10 cm gadoxetate-retaining lesion within the right hepatic lobe with imaging features suggestive of HCA vs focal nodular hyperplasia . Within this lesion was a focus of arterial enhancement with venous washout suggestive of hepatocellular carcinoma (HCC) within HCA, later confirmed at surgical resection. Understanding the imaging characteristics of HCAs as well as their rare ability to undergo malignant transformation is useful in differentiating HCAs from focal nodular hyperplasia.

Effect of travel distance and rurality of residence on initial surveillance for hepatocellular carcinoma in VA primary care patient with cirrhosis

OBJECTIVE

To determine the relationship between travel distance and surveillance for hepatocellular carcinoma among veterans with cirrhosis.

DATA SOURCES

Veterans Health Administration (VHA) inpatient and outpatient administrative data were linked to geocoded enrollee files. CMS-VHA merged data were used to assess receipt of Medicare-financed non-VA imaging.

STUDY DESIGN

A retrospective cohort of US veterans diagnosed with cirrhosis between 2009 and 2015 was examined. First available abdominal imaging following the diagnosis of cirrhosis was analyzed separately as a function of travel distance to the nearest VA medical center (VAMC) and to the patient's assigned VA primary care provider. Veterans with dual use of Medicare and VA services were also examined for receipt of imaging outside of the VA.

PRINCIPAL FINDINGS

Veterans who resided more than 30 miles from the nearest VAMC were less likely to receive any imaging for HCC surveillance. Among dual users, increased travel distance between the patient's residence and nearest VAMC was associated with an increased likelihood of receiving any abdominal imaging at non-VA facilities.

CONCLUSION

Increased travel distance to the nearest VA medical center reduces the likelihood of receiving imaging for HCC surveillance in cirrhotic veterans. Future efforts should focus on reducing geographic barriers to HCC surveillance.

Multicentre study on dynamic contrast computed tomography findings of focal liver lesions with clinical and histological correlation

BACKGROUND

Current advancements in dynamic contrast imaging of the liver have enabled increased sensitivity in the diagnosis of liver lesions. Evaluation and characterisation of the enhancement pattern of liver lesions in respect to the liver parenchyma aids in making a specific diagnosis.

OBJECTIVES

The aim of this study was to determine the liver findings on dynamic contrast computed tomography (CT) scanning and correlate them with clinicopathologic findings.

METHODS

This prospective cross-sectional study included 61 patients and took place between August 2017 and February 2018. Dynamic contrast CT was performed and the images were evaluated by two experienced radiologists. Correlation of the CT findings with histology results from an ultrasound-guided biopsy was done. Data analysis was performed using SPSS version 20.0.

RESULTS

Hepatocellular carcinoma (HCC) was the most common malignant lesion seen and showed three patterns of enhancement: homogenous, abnormal internal vessels and heterogeneous enhancement. Abnormal internal vessel pattern was most specific (90.6%) and showed a high positive predictive value (PPV) of 78.6%. Rapid washout showed a specificity of 87.5% and a PPV of 72.2% in the diagnosis of HCC. Dynamic contrast CT scan had a sensitivity of 93%, specificity of 50%, PPV of 91% and diagnostic accuracy of 95.5% in differentiation of benign and malignant liver lesions. Considering only Liver Imaging Reporting and Data System (LI-RADS) category 5 as conclusive for HCC diagnosis, our study did not miss a significant number of HCCs. Liver Imaging Reporting and Data System category 5 showed specificity of 81.3% and PPV of 75%.

CONCLUSION

Enhancement patterns on a dynamic contrast CT scan of the liver are useful in the interpretation of CT images for specific diagnoses.

Simple hepatic cyst rupture exacerbated by anticoagulation

Simple hepatic cysts are usually asymptomatic but can rarely result in life-threatening complications such as haemoperitoneum secondary to rupture. A 70-year-old woman with known simple hepatic cyst presented with acute chest pain and dyspnoea. The initial diagnosis was pulmonary embolism, and anticoagulation was commenced. However, she subsequently collapsed with haemodynamic instability. CT revealed a large hepatic cyst haematoma with rupture into the peritoneal cavity. The patient underwent emergency laparotomy, haemostasis and partial deroofing of the cyst. Retrospective review of CT scans suggested that the bleed had begun on presentation but was exacerbated by anticoagulation. To our knowledge, this is the first report of haemorrhagic hepatic cyst associated with acute anticoagulation. We discuss several important clinical lessons including cyst rupture as a possible cause of chest pain, the need for careful review of imaging and the choice of anticoagulation in patients with known simple hepatic cyst.