Generative adversarial networks (GAN)-based data augmentation of rare liver cancers: The SFR 2021 Artificial Intelligence Data Challenge

PURPOSE

The 2021 edition of the Artificial Intelligence Data Challenge was organized by the French Society of Radiology together with the Centre National d'Études Spatiales and CentraleSupélec with the aim to implement generative adversarial networks (GANs) techniques to provide 1000 magnetic resonance imaging (MRI) cases of macrotrabecular-massive (MTM) hepatocellular carcinoma (HCC), a rare and aggressive subtype of HCC, generated from a limited number of real cases from multiple French centers.

MATERIALS AND METHODS

A dedicated platform was used by the seven inclusion centers to securely upload their anonymized MRI examinations including all three cross-sectional images (one late arterial and one portal-venous phase T1-weighted images and one fat-saturated T2-weighted image) in compliance with general data protection regulation. The quality of the database was checked by experts and manual delineation of the lesions was performed by the expert radiologists involved in each center. Multidisciplinary teams competed between October 11^th, 2021 and February 13^th, 2022.

RESULTS

A total of 91 MTM-HCC datasets of three images each were collected from seven French academic centers. Six teams with a total of 28 individuals participated in this challenge. Each participating team was asked to generate one thousand 3-image cases. The qualitative evaluation was performed by three radiologists using the Likert scale on ten randomly selected cases generated by each participant. A quantitative evaluation was also performed using two metrics, the Frechet inception distance and a leave-one-out accuracy of a 1-Nearest Neighbor algorithm.

CONCLUSION

This data challenge demonstrates the ability of GANs techniques to generate a large number of images from a small sample of imaging examinations of a rare malignant tumor.

Reperfusion injury on computed tomography following endovascular revascularization of acute mesenteric ischemia: prevalence, risk factors, and patient outcome

BACKGROUND

Data about reperfusion injury (RI) following acute arterial mesenteric ischemia (AAMI) in humans are scarce. We aimed to assess the prevalence and risk factors of RI following endovascular revascularization of AMI and evaluate its impact on patient outcomes.

METHODS

Patients with AAMI who underwent endovascular revascularization (2016-2021) were included in this retrospective cohort. CT performed < 7 days after treatment was reviewed to identify features of RI (bowel wall hypoattenuation, mucosal hyperenhancement). Clinical, laboratory, imaging, and treatments were compared between RI and non-RI patients to identify factors associated with RI. Resection rate and survival were also compared.

RESULTS

Fifty patients (23 men, median 72-yrs [IQR 60-77]) were included, and 22 were diagnosed with RI (44%) after a median 28 h (22-48). Bowel wall hypoattenuation and mucosal hyperenhancement were found in 95% and 91% of patients with post-interventional RI, respectively. Patients with RI had a greater increase of CRP levels after endovascular treatment (p = 0.01). On multivariate analysis, a decreased bowel wall enhancement on baseline CT (HR = 8.2), an embolic cause (HR = 7.4), complete SMA occlusion (HR = 7.0), and higher serum lactate levels (HR = 1.4) were associated with RI. The three-month survival rate was 78%, with no difference between subgroups (p = 0.99). However, the resection rate was higher in patients with RI (32% versus 7%; p = 0.03).

CONCLUSION

RI is frequent after endovascular revascularization of AAMI, especially in patients who present with decreased bowel wall enhancement on pre-treatment CT, an embolic cause, and a complete occlusion of the SMA. However, its occurrence does not seem to negatively impact short-term survival.

Rivaroxaban Prophylaxis in Noncirrhotic Portal Vein Thrombosis

BACKGROUND: In patients with noncirrhotic chronic portal vein thrombosis (PVT), the benefit of long-term anticoagulation is unknown. We assessed the effects of rivaroxaban on the risk of venous thromboembolism and portal hypertension-related bleeding in such patients. METHODS: In this multicenter, controlled trial, we randomly assigned patients with noncirrhotic chronic PVT without major risk factors for thrombosis to receive either rivaroxaban 15 mg/day or no anticoagulation. The primary end point was 2-year thrombosis-free survival. Secondary end points included the occurrence of site-specific thromboses and major bleeding events. RESULTS: A total of 111 participants were enrolled in the trial, with a mean age of 50.4±13.2 years; 58% of participants were men. An unplanned interim analysis was requested by the independent data safety monitoring board (DSMB) after 10 thrombotic events occurred. The thrombosis incidence rate was 0 per 100 person-years in the rivaroxaban group and 19.71 per 100 person-years (95% confidence interval, 7.49 to 31.92) in the no anticoagulation group (log-rank P=0.0008) after a median follow-up of 11.8 months. Based on the interim analysis, the DSMB recommended switching patients from the no anticoagulation group to anticoagulation. After a median follow-up of 30.3 months (intraquartile range, 24.3 to 47.8), major bleeding occurred in two patients receiving rivaroxaban and in one patient not receiving anticoagulation. No deaths occurred. CONCLUSIONS: After a median follow-up of 11.8 months, among patients with noncirrhotic chronic PVT without major risk factors for thrombosis, daily rivaroxaban reduced the incidence of venous thromboembolism and did not increase major bleeding events. (Funded by grants from the French Ministry of Health and the Association de Malades des Vaisseaux du foie; ClinicalTrials.gov number, NCT02555111.)

Laparoscopic-assisted liver transplantation: A realistic perspective

Laparoscopic approach was rarely described in recipients for liver transplantation (LT). We report the feasibility and safety of laparoscopic-assisted LT (LA-LT) in patients with unresectable liver metastases of neuroendocrine tumors. Total hepatectomy was performed laparoscopically with graft implantation through an upper midline incision. Liver grafts were retrieved from deceased donors. From July 2019 to July 2021, six patients (4 women, 2 men) underwent LA-LT. Median age and BMI were 46 (29-54) and 24 (19-35) kg/m² , respectively. Implanted grafts were reduced (n = 3), full (n = 2), and a right split liver (n = 1). Median surgical time was 405 min (390-450) and median blood loss was 425 ml (250-600). Median cold and warm ischemia times were 438 min (360-575) and 35 min (30-40), respectively. Median anhepatic phase was 51 min (40-67) and midline incision was 14 cm (13-20) long. On postoperative day 5, median prothrombin index and serum bilirubin levels were 95% (70-117) and 11 (10-37) μmol/L, respectively. No Clavien-Dindo > III complications were encountered. Median hospital stay was 12 days (10-14). After a median follow-up of 8 (8-32) months, all patients were alive without tumor recurrence or adverse event. This preliminary series suggests that in selected patients, LA-LT is a safe and effective option.

Predicting bleeding after liver biopsy using comprehensive clinical and laboratory investigations: A prospective analysis of 302 procedures

BACKGROUND

Liver biopsy carries a small risk of bleeding complications. No validated clinical or laboratory tool helps predict liver biopsy-related bleeding.

OBJECTIVES

To determine whether global hemostasis tests and/or a clinical questionnaire could identify patients at risk of liver biopsy-related bleeding.

PATIENTS/METHODS

Consecutive patients scheduled for liver biopsy with an overnight hospital stay were prospectively included. Before liver biopsy, routine hemostasis tests, Platelet Function Analyzer 100, thromboelastometry, thrombin generation assay, plasma clot lysis time, and a clinical questionnaire were performed. Bleeding was defined as a liver hematoma or new free fluid on a systematic ultrasound performed 24 h after liver biopsy or a decrease in hemoglobin level of 2 g/dL or more in patients with pre-existing free fluid in the abdominal cavity.

RESULTS

Three hundred two patients were included: 173 underwent percutaneous and 129 transjugular liver biopsy. There were 21 bleeding episodes (7%); 20 based on ultrasonographic criteria, 1 on laboratory criteria. None of the hemostasis tests and no item of the clinical questionnaire were associated with liver biopsy-related bleeding in the overall study group. Same results were obtained in subgroup analyses focusing on patients who underwent percutaneous liver biopsy, transjugular liver biopsy, or on patients with cirrhosis. Pain 2 h after liver biopsy was more frequent in patients with liver biopsy-related bleeding (55% vs. 23% p = .002).

CONCLUSIONS

An extensive hemostasis workup, including global hemostasis assays, does not improve prediction of liver biopsy-related bleeding. Pain 2 h after liver biopsy should alert the clinician to the possibility of procedure-related bleeding.

Summary of key guidelines for locoregional treatment of HCC in Asia, Europe, South and North America

Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide accounting for over 800,000 new cases in 2018, with the highest incidence in Asia and Africa where hepatitis B is the most common risk factor. In Europe, Japan, and the United States, hepatitis C chronic alcohol abuse and non-alcoholic fatty liver disease are more common risk factors. Five-year survival is low, less than 20% worldwide. HCC is a particularly challenging disease to treat because therapeutic options and prognosis must also consider hepatitis or cirrhosis independent of the malignancy. Locoregional therapies (LRT) including ablation, arterially directed therapy and external beam radiation are the preferred treatments for patients with good performance status, unresectable disease limited to the liver and preserved liver function. In practice, patients with portal vein tumor thrombus and limited extrahepatic disease may also be considered candidates for LRT. There are several guidelines developed by expert panels provide recommendations on treating this challenging disease including the Barcelona Clinic Liver Cancer, European Association for the Study of the Liver, European Society for Medical Oncology, American Association for the Study of the Liver Diseases, and the National Comprehensive Cancer Network. The purpose of this paper is to review the guidelines as they are applied clinically in regions with high incidence of HCC.

Contrast-enhanced CT and liver surface nodularity for the diagnosis of porto-sinusoidal vascular disorder: A case-control study

BACKGROUND AND AIMS

Porto-sinusoidal vascular disorder (PSVD) is a rare and commonly overlooked cause of portal hypertension. The interest of CT analysis, including quantification of liver surface nodularity (LSN) for PSVD diagnosis has not been established. This study aimed at assessing the performance of LSN and CT features for a PSVD diagnosis in patients with signs of portal hypertension.

APPROACH AND RESULTS

This retrospective case-control study included a learning cohort consisting of 50 patients with histologically proven PSVD, according to VALDIG criteria, and 100 control patients with histologically proven cirrhosis, matched on ascites. All patients and controls had at least one sign of portal hypertension and CT available within 1 year of liver biopsy. Principal component analysis of CT features separated patients with PSVD from patients with cirrhosis. Patients with PSVD had lower median LSN than those with cirrhosis (2.4 vs. 3.1, p < 0.001). Multivariate analysis identified LSN < 2.5 and normal-sized or enlarged segment IV as independently associated with PSVD. Combination of these two features had a specificity of 90% for PSVD and a diagnostic accuracy of 84%. Even better results were obtained in an independent multicenter validation cohort including 53 patients with PSVD and 106 control patients with cirrhosis (specificity 94%, diagnostic accuracy 87%).

CONCLUSIONS

This study that included a total of 103 patients with PSVD and 206 patients with cirrhosis demonstrates that LSN < 2.5 combined with normal-sized or enlarged segment IV strongly suggests PSVD in patients with signs of portal hypertension.

Outcome of liver cancer patients with SARS-CoV-2 infection: An International, Multicentre, Cohort Study

BACKGROUND & AIMS

Information about the impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in patients with liver cancer is lacking. This study characterizes the outcomes and mortality risk in this population.

METHODS

Multicentre retrospective, cross-sectional, international study of liver cancer patients with SARS-CoV-2 infection registered between February and December 2020. Clinical data at SARS-CoV-2 diagnosis and outcomes were registered.

RESULTS

Two hundred fifty patients from 38 centres were included, 218 with hepatocellular carcinoma (HCC) and 32 with intrahepatic cholangiocarcinoma (iCCA). The median age was 66.5 and 64.5 years, and 84.9% and 21.9% had cirrhosis in the HCC and iCCA cohorts respectively. Patients had advanced cancer stage at SARS-CoV-2 diagnosis in 39.0% of the HCC and 71.9% of the iCCA patients. After a median follow-up of 7.20 (IQR: 1.84-11.24) months, 100 (40%) patients have died, 48% of the deaths were SARS-CoV-2-related. Forty (18.4%) HCC patients died within 30-days. The death rate increase was significantly different according to the BCLC stage (6.10% [95% CI 2.24-12.74], 11.76% [95% CI 4.73-22.30], 20.69% [95% CI 11.35-31.96] and 34.52% [95% CI 17.03-52.78] for BCLC 0/A, B, C and D, respectively; p = .0017). The hazard ratio was 1.45 (95% CI 0.49-4.31; p = .5032) in BCLC-B versus 0/A, and 3.13 (95% CI 1.29-7.62; p = .0118) in BCLC-C versus 0/A in the competing risk Cox regression model. Nineteen out of 32 iCCA (59.4%) died, and 12 deaths were related to SARS-CoV-2 infection.

CONCLUSIONS

This is the largest cohort of liver cancer patients infected with SARS-CoV-2. It characterizes the 30-day mortality risk of SARS-CoV-2 infected patients with HCC during this period.

Conventional and artificial intelligence-based imaging for biomarker discovery in chronic liver disease

Chronic liver diseases, resulting from chronic injuries of various causes, lead to cirrhosis with life-threatening complications including liver failure, portal hypertension, hepatocellular carcinoma. A key unmet medical need is robust non-invasive biomarkers to predict patient outcome, stratify patients for risk of disease progression and monitor response to emerging therapies. Quantitative imaging biomarkers have already been developed, for instance, liver elastography for staging fibrosis or proton density fat fraction on magnetic resonance imaging for liver steatosis. Yet, major improvements, in the field of image acquisition and analysis, are still required to be able to accurately characterize the liver parenchyma, monitor its changes and predict any pejorative evolution across disease progression. Artificial intelligence has the potential to augment the exploitation of massive multi-parametric data to extract valuable information and achieve precision medicine. Machine learning algorithms have been developed to assess non-invasively certain histological characteristics of chronic liver diseases, including fibrosis and steatosis. Although still at an early stage of development, artificial intelligence-based imaging biomarkers provide novel opportunities to predict the risk of progression from early-stage chronic liver diseases toward cirrhosis-related complications, with the ultimate perspective of precision medicine. This review provides an overview of emerging quantitative imaging techniques and the application of artificial intelligence for biomarker discovery in chronic liver disease.

Differentiation of hepatocellular adenoma by subtype and hepatocellular carcinoma in non-cirrhotic liver by fractal analysis of perfusion MRI

Background

To investigate whether fractal analysis of perfusion differentiates hepatocellular adenoma (HCA) subtypes and hepatocellular carcinoma (HCC) in non-cirrhotic liver by quantifying perfusion chaos using four-dimensional dynamic contrast-enhanced magnetic resonance imaging (4D-DCE-MRI).

Results

A retrospective population of 63 patients (47 female) with histopathologically characterized HCA and HCC in non-cirrhotic livers was investigated. Our population consisted of 13 hepatocyte nuclear factor (HNF)-1α-inactivated (H-HCAs), 7 β-catenin-exon-3-mutated (b^ex3-HCAs), 27 inflammatory HCAs (I-HCAs), and 16 HCCs. Four-dimensional fractal analysis was applied to arterial, portal venous, and delayed phases of 4D-DCE-MRI and was performed in lesions as well as remote liver tissue. Diagnostic accuracy of fractal analysis was compared to qualitative MRI features alone and their combination using multi-class diagnostic accuracy testing including kappa-statistics and area under the receiver operating characteristic curve (AUC). Fractal analysis allowed quantification of perfusion chaos, which was significantly different between lesion subtypes (multi-class AUC = 0.90, p < 0.001), except between I-HCA and HCC. Qualitative MRI features alone did not allow reliable differentiation between HCA subtypes and HCC (κ = 0.35). However, combining qualitative MRI features and fractal analysis reliably predicted the histopathological diagnosis (κ = 0.89) and improved differentiation of high-risk lesions (i.e., HCCs, b^ex3-HCAs) and low-risk lesions (H-HCAs, I-HCAs) from sensitivity and specificity of 43% (95% confidence interval [CI] 23–66%) and 47% (CI 32–64%) for qualitative MRI features to 96% (CI 78–100%) and 68% (CI 51–81%), respectively, when adding fractal analysis.

Conclusions

Combining qualitative MRI features with fractal analysis allows identification of HCA subtypes and HCCs in patients with non-cirrhotic livers and improves differentiation of lesions with high and low risk for malignant transformation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13244-022-01223-6.

Colonic involvement in acute mesenteric ischemia: prevalence, risk factors, and outcomes

OBJECTIVES

This study aimed to investigate the prevalence, risk factors, and outcomes of colonic involvement in patients with acute mesenteric ischemia (AMI).

METHODS

CT scans from a prospective cohort of 114 AMI patients treated in an intestinal stroke center between 2009 and 2018 were blindly reviewed by two radiologists. Colon involvement was defined on CT scan by the presence of at least one of the following CT colonic features: wall thickening, pneumatosis, decreased wall enhancement, dilatation, or perforation. In addition, the clinical, biological, and radiological characteristics of patients with and without colonic involvement were compared to identify risk factors for colonic involvement on CT and its impact on morbidity and mortality.

RESULTS

Colonic involvement was identified in 32/114 (28%) patients with AMI, the right colon being more frequently involved (n = 29/32, 91%). Wall thickening (n = 27/32) was the most common CT finding. Occlusion of the inferior mesenteric artery was the only statistically significant risk factor for colonic involvement (35% vs. 15%, p = 0.02). Patients with colonic involvement on CT vs. those without had more frequently transmural colonic necrosis (13% vs. 0%, p = 0.006), short bowel syndrome (16% vs. 4%, p = 0.04), need for long-term parenteral support (19% vs. 5%, p = 0.03), and death during follow-up (22% vs. 10%, p = 0.03).

DISCUSSION

In patients with AMI, colonic involvement is associated with increased morbidity and mortality and should be carefully searched for during initial CT scan assessment.

KEY POINTS

• In a prospective cohort of acute mesenteric ischemia patients from an intestinal stroke center, 28% had an associated colonic involvement on CT. • Colonic involvement on CT most commonly affected the right colon, and the occlusion of the inferior mesenteric artery was the only risk factor. • Colonic involvement on CT was associated with increased morbidity and mortality and should be carefully searched for during initial CT scan assessment.

Endovascular revascularization of acute arterial mesenteric ischemia: report of a 3-year experience from an intestinal stroke center unit

OBJECTIVE

To report the 3-year experience of endovascular revascularization of acute arterial mesenteric ischemia (AMI) from an intestinal stroke center unit (ISCU).

METHOD

All data from patients admitted to the ISCU between January 2016 and January 2019 for arterial AMI who underwent endovascular recanalization were prospectively acquired and retrospectively analyzed. Patient demographics, clinical and laboratory characteristics at presentation, and CT scans were reviewed. The type (thrombolysis, thrombectomy, stenting) and the outcome of endovascular procedures (technical success or failure, complications) were noted. Care pathways were described focusing on post-procedural treatments (surgical revascularization, bowel resection) and the mortality rate was evaluated in subgroups.

RESULTS

Fifty-eight patients (34 men [59%], mean 69 ± 29 years) were included. Endovascular revascularization was technically successful in 51/58 (88%) patients, and 10 (17%) patients had post-procedural complications. Stenting and in situ thrombolysis were performed in most patients (n = 33 and n = 19, respectively). Thirty-two patients (55%) were recurrence-free and required no further treatment after the procedure, while 9 (16%), 5 (9%), and 5 (9%) patients underwent 2nd-line bowel resection, surgical revascularization, or both. Overall, 46 (79%), 45 (78%), and 34 patients (63%) were alive at 3 months, 1 year, and 3 years. No significant difference in survival was found in care pathways or baseline characteristics.

CONCLUSION

Endovascular revascularization is highly feasible for the treatment of arterial AMI, and is associated with an acceptable rate of complications. Results of endovascular revascularization shall only be interpreted as part of a multidisciplinary patient management strategy.

KEY POINTS

• Endovascular revascularization is highly feasible for the treatment of arterial AMI, and is associated with an acceptable rate of complications. • Several techniques are available to perform endovascular revascularization, and their use depends on the cause, the location, and the quality of underlying arteries of patients. • Results of endovascular revascularization shall only be interpreted in relation to its role in an integrated multidisciplinary and patient management strategy.

Reliability Criteria of Two-Dimensional Shear Wave Elastography: Analysis of 4277 Measurements in 788 Patients

BACKGROUND & AIMS

Two-dimensional shear wave elastography (2D-SWE) is an accurate method for the non-invasive evaluation of liver fibrosis. We aimed to determine the reliability criteria and the number of necessary reliable measurements for 2D-SWE.

METHODS

788 patients with chronic liver disease underwent liver biopsy and 2D-SWE examination in three centers. The 4277 2D-SWE measurements performed were 2:1 randomly divided into derivation (n = 2851) and validation (n = 1426) sets. Reliability criteria for a 2D-SWE measurement were defined in the derivation set from the intrinsic characteristics given by the device (mean liver stiffness, standard deviation, diameter of the region of interest), with further evaluation in the validation set.

RESULTS

In the whole population of 4277 measurements, AUROC for bridging fibrosis was 0.825 ± 0.006 and AUROC for cirrhosis was 0.880 ± 0.006. Mean stiffness and coefficient of variation (CV) were independent predictors of bridging fibrosis or cirrhosis. From these two parameters, new criteria were derived to define a reliable 2D-SWE measurement: stiffness <8.8 kPa, or stiffness between 8.8-11.9 kPa with CV <0.25, or stiffness ≥12.0 kPa with CV <0.10. In the validation set, AUROC for bridging fibrosis was 0.830 ± 0.013 in reliable measurements vs 0.667 ± 0.031 in unreliable measurements (P < .001). AUROC for cirrhosis was 0.918±0.014 vs 0.714 ± 0.027, respectively (P < .001). The best diagnostic accuracy for a 2D-SWE examination was achieved from three reliable measurements.

CONCLUSIONS

Reliability of a 2D-SWE measurement relies on the coefficient of variation and the liver stiffness level. A 2D-SWE examination should include three reliable measurements according to our new criteria.

Gene expression signature as a surrogate marker of microvascular invasion on routine hepatocellular carcinoma biopsies

BACKGROUND & AIMS

Microvascular invasion (MVI), a major risk factor for tumor recurrence after surgery in hepatocellular carcinoma (HCC), is only detectable by microscopic examination of the surgical specimen. We aimed to define a transcriptomic signature associated with MVI in HCC than can be applied to formalin-fixed paraffin-embedded (FFPE) biopsies for use in clinical practice.

METHODS

To identify a gene expression signature related to MVI by using NanoString technology, we selected a set of 200 genes according to the literature and RNA-sequencing data obtained from a cohort of 150 frozen HCC samples previously published. We used 178 FFPE-archived HCC samples, including 109 surgical samples for the training set and 69 paired pre-operative biopsies for the validation set. In 14 cases of the training set, a paired biopsy was available and was also analyzed.

RESULTS

We identified a 6-gene signature (ROS1, UGT2B7, FAS, ANGPTL7, GMNN, MKI67) strongly associated with MVI in the training set of FFPE surgical HCC samples, with 82% accuracy (sensitivity 82%, specificity 81%, AUC 0.82). The NanoString gene expression was highly correlated in 14 paired surgical/biopsy HCC samples (mean R: 0.97). In the validation set of 69 FFPE HCC biopsies, the 6-gene NanoString signature predicted MVI with 74% accuracy (sensitivity 73%, specificity 76%, AUC 0.74). Moreover, on multivariate analysis, the MVI signature was associated with overall survival in both sets (hazard ratio 2.29; 95% CI 1.03-5.07; p = 0.041).

CONCLUSION

We defined a 6-gene signature that can accurately predict MVI in FFPE HCC biopsy samples, which is also associated with overall survival, although its survival impact must be confirmed by extensive study with further clinical data.

LAY SUMMARY

Microvascular invasion, a major risk factor for tumor recurrence after surgery in hepatocellular carcinoma, is only detectable by microscopic examination of a surgical specimen. In this study, we defined a relevant surrogate signature of microvascular invasion in hepatocellular carcinoma that may be applied in clinical practice with routine tumor biopsy and integrated into the therapeutic strategy.

Multicenter study on recent portal venous system thrombosis associated with cytomegalovirus disease

BACKGROUND & AIMS

Recent non-malignant non-cirrhotic portal venous system thrombosis (PVT) is a rare condition. Among risk factors for PVT, cytomegalovirus (CMV) disease is usually listed based on a small number of reported cases. The aim of this study was to determine the characteristics and outcomes of PVT associated with CMV disease.

METHODS

We conducted a French multicenter retrospective study comparing patients with recent PVT and CMV disease ("CMV positive"; n = 23) to patients with recent PVT for whom CMV testing was negative ("CMV negative"; n = 53) or unavailable ("CMV unknown"; n = 297).

RESULTS

Compared to patients from the "CMV negative" and "CMV unknown" groups, patients from the "CMV positive" group were younger, more frequently had fever, and had higher heart rate, lymphocyte count and serum ALT levels (p ≤0.01 for all). The prevalence of immunosuppression did not differ between the 3 groups (4%, 4% and 6%, respectively). Extension of PVT was similar between the 3 groups. Thirteen out of 23 "CMV positive" patients had another risk factor for thrombosis. Besides CMV disease, the number of risk factors for thrombosis was similar between the 3 groups. Heterozygosity for the prothrombin G20210A gene variant was more frequent in "CMV positive" patients (22%) than in the "CMV negative" (4%, p = 0.01) and "CMV unknown" (8%, p = 0.03) groups. Recanalization rate was not influenced by CMV status.

CONCLUSIONS

In patients with recent PVT, features of mononucleosis syndrome should raise suspicion of CMV disease. CMV disease does not influence thrombosis extension nor recanalization. More than half of "CMV positive" patients have another risk factor for thrombosis, with a particular link to the prothrombin G20210A gene variant.

LAY SUMMARY

Patients with cytomegalovirus (CMV)-associated portal venous system thrombosis have similar thrombosis extension and evolution as patients without CMV disease. However, patients with CMV-associated portal venous system thrombosis more frequently have the prothrombin G20210A gene variant, suggesting that these entities act synergistically to promote thrombosis.

Non-invasive diagnosis and follow-up of vascular liver diseases

Vascular disorders of the liver are rare diseases, some of which are diagnosed mainly with non-invasive tests and others by liver biopsy. Non-invasive methods can be used to diagnose and monitor these diseases. However, their evaluation needs to be performed by expert centers. Liver biopsy is needed each time there is an unexplained abnormality.

Imaging features of histological subtypes of hepatocellular carcinoma: Implication for LI-RADS

Background & Aims

The histopathological subtypes of hepatocellular carcinoma (HCC) are associated with distinct clinical features and prognoses. This study aims to report Liver Imaging Reporting and Data System (LI-RADS)-defined imaging features of different HCC subtypes in a cohort of resected tumours and to assess the influence of HCC subtypes on computed tomography (CT)/magnetic resonance imaging (MRI) LI-RADS categorisation in the subgroup of high-risk patients.

Methods

This retrospective institutional review board-approved study included patients with resected HCCs and available histopathological classification. Three radiologists independently reviewed preoperative CT and MRI exams. The readers evaluated the presence of imaging features according to LI-RADS v2018 definitions and provided a LI-RADS category in patients at high risk of HCC. Differences in LI-RADS features and categorisations were assessed for not otherwise specified (NOS-HCC), steatohepatitic (SH-HCC), and macrotrabecular-massive (MTM-HCC) types of HCCs.

Results

Two hundred and seventy-seven patients (median age 64.0 years, 215 [77.6%] men) were analysed, which involved 295 HCCs. There were 197 (66.7%) NOS-HCCs, 62 (21.0%) SH-HCCs, 23 (7.8%) MTM-HCCs, and 13 (4.5%) other rare subtypes. The following features were more frequent in MTM-HCC: elevated α-foetoprotein serum levels (p <0.001), tumour-in-vein (p <0.001 on CT, p ≤0.052 on MRI), presence of at least 1 LR-M feature (p ≤0.010 on CT), infiltrative appearance (p ≤0.032 on CT), necrosis or severe ischaemia (p ≤0.038 on CT), and larger size (p ≤0.006 on CT, p ≤0.011 on MRI). SH-HCC was associated with fat in mass (p <0.001 on CT, p ≤0.002 on MRI). The distribution of the LI-RADS major features and categories in high-risk patients did not significantly differ among the 3 main HCC subtypes.

Conclusions

The distribution of LI-RADS major features and categories is not different among the HCC subtypes. Nevertheless, careful analysis of tumour-in-vein, LR-M, and ancillary features as well as clinico-biological data can provide information for the non-invasive diagnosis of HCC subtypes.

Lay summary

In high-risk patients, the overall distribution of LI-RADS major features and categories is not different among the histological subtypes of hepatocellular carcinoma, but tumour-in-vein, presence of LR-M features, and ancillary features can provide information for the non-invasive diagnosis of hepatocellular carcinoma subtypes.

•

The distribution of the major features and categories of LI-RADS is not different among the HCC histological subtypes.

•

MTM-HCC was associated with TIV, ≥1 LR-M feature, infiltrative appearance, necrosis or severe ischaemia, and larger size.

•

Steatohepatitis-related HCC was associated with fat in mass on CT and on MRI.

Segmental Arterial Mediolysis

Online supplemental material is available for this article.

Percutaneous ablation for locally advanced hepatocellular carcinoma with tumor portal invasion

INTRODUCTION

We aim to assess the outcomes of percutaneous ablation of locally advanced HCC in a tertiary center, which is usually not indicated. We compared to sorafenib or trans-arterial radioembolization (TARE).

METHODS

We included 272 patients with HCC and tumor portal invasion treated by percutaneous ablation (n = 44) assessed retrospectively from one center compared to a control group from the SARAH trial including patients treated with sorafenib (n = 123) or TARE (n = 105). A propensity-score matching was performed in a subgroup of patients with similar baselines characteristics.

RESULTS

84% of patients treated by ablation were male with a unique nodule (median size 50 mm) in 72.7% of the case. Complete tumor ablation was achieved in 75% of the patients with 20% Dindo-Clavien III-V adverse events including 6.8% of 90-days mortality. Sum of tumor size ≥70 mm was associated with incomplete ablation (p = 0.0239) and a higher risk of death (p = 0.0375). Patients in control group had a higher tumor burden, and more Vp3/4 compared to ablation group. Median overall survival was similar in the ablation and in the control group (16.4 and 14.0 months respectively, p = 0.48). The median progression-free survival was 6.6 months in ablation group compared to 4.2 months in the control group (p = 0.12).

CONCLUSION

Percutaneous ablation for locally advanced HCC was feasible and associated with similar long-term outcomes to sorafenib or TARE.

Autofluorescence imaging within the liver: a promising tool for the detection and characterization of primary liver tumors

OBJECTIVES

To assess the performance of 405 nm-induced autofluorescence for the characterization of primary liver nodules on ex vivo resected specimens.

MATERIALS AND METHODS

Forty resected liver specimens bearing 53 primary liver nodules were included in this IRB-approved prospective study. Intratissular spectroscopic measurements were performed using a 25-G fibered-needle on all ex vivo specimens: 5 autofluorescence measurements were performed in both nodules and adjacent parenchyma. The spectra derivatives of the 635 and 670 nm autofluorescence peaks observed in nodules and in adjacent liver parenchyma were compared (Kruskal-Wallis and Mann-Whitney when appropriate).

RESULTS

A total of 42 potentially evolutive primary liver nodules-34 hepatocellular carcinomas, 4 intrahepatic cholangiocarcinomas, 4 hepatocellular adenomas-and 11 benign nodules-5 focal nodular hyperplasias, 6 regenerative nodules-were included. Both 635 and 670 nm Δderivatives were significantly higher in benign as compared to potentially evolutive (PEV) nodules (respectively 32.9 ± 4.5 vs 15.3 ± 1.4; p < 0.0001 and 5.7 ± 0.6 vs 2.5 ± 0.1; p < 0.0001) with respective sensitivity and specificity of 78% and 91% for distinguishing PEV from benign nodules.

CONCLUSION

405 nm-induced autofluorescence enables the discrimination of benign from PEV primary liver nodules, suggesting that autofluorescence imaging could be used to optimize US targeted liver biopsies.

KEY POINTS

• 405 nm-induced autofluorescence can distinguish liver tumors from the adjacent liver parenchyma. • The analysis of autofluorescence imaging observed within primary liver tumors can discriminate benign tumors from those requiring follow-up or targeted liver biopsy. • In current practice, autofluorescence imaging could be embedded within biopsy needle, to enable, in addition to ultrasound guidance, optimal targeting of liver nodules which could optimize tissue sampling.

2D-shear wave elastography: number of acquisitions can be reduced according to clinical setting

Background

The factors affecting intra-operator variability of two-dimensional shear wave elastography (2D-SWE) have not been clearly established. We evaluated 2D-SWE variability according to the number of measurements, clinical and laboratory features, and liver stiffness measurements (LSM).

Methods

At least three LSM were performed in 452 patients who underwent LSM by 2D-SWE (supersonic shear imaging) out of an initial database of 1650 patients. The mean value of the three LSM was our best measurement method. Bland–Altman plots were used to evaluate intra-operator variability when considering only one, or the first two measurements. Variability was assessed by taking the absolute value of the difference between the first LSM and the mean of the three LSM. Logistic regression was used to assess the factors associated with the highest tertile of variability.

Results

The limit of agreement was narrower with the mean of the first and second measurements than with each measurement taken separately (− 2.83 to 2.99 kPa vs. − 5.86 to 6.21 kPa and − 5.77 to 5.73 kPa for the first and second measurement, respectively). A BMI ≥ 25 kg/m² and a first LSM by 2D-SWE ≥ 7.1 kPa increased the odds of higher variability by 3.4 and 3.9, respectively. Adding a second LSM didn’t change the variability in patients with BMI < 25 and a first LSM by 2D-SWE < 7.1 kPa.

Conclusions

Intra-operator variability of LSM by 2D-SWE increases with both a high BMI and high LSM value. In patients with BMI < 25 kg/m² and a first LSM < 7.1 kPa we recommend performing only one LSM.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13244-021-01090-7.

Pathologic, Molecular, and Prognostic Radiologic Features of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a malignancy with variable biologic aggressiveness based on the tumor grade, presence or absence of vascular invasion, and pathologic and molecular classification. Knowledge and understanding of the prognostic implications of different pathologic and molecular phenotypes of HCC are emerging, with therapeutics that promise to provide improved outcomes in what otherwise remains a lethal cancer. Imaging has a central role in diagnosis of HCC. However, to date, the imaging algorithms do not incorporate prognostic features or subclassification of HCC according to its biologic aggressiveness. Emerging data suggest that some imaging features and further radiologic, pathologic, or radiologic-molecular phenotypes may allow prediction of the prognosis of patients with HCC. An invited commentary by Bashir is available online. Online supplemental material is available for this article. ^©RSNA, 2021.