Improving Outcome of Selected Patients With Non-Resectable Hepatic Metastases From Colorectal Cancer With Liver Transplantation: A Prospective Parallel Trial (COLT trial)

BACKGROUND

Patients with unresectable Colorectal Liver Metastases (CLM) receiving palliative chemotherapy have a 5-year overall survival (OS) of less than 30%. Liver transplantation (LT) can improve OS up to 60%-83% (SECA-I and SECA-II trials). The aim of the study is to assess the efficacy of LT in liver-only metastatic CRC compared with a matched cohort of patients included in a phase III trial on triplet chemotherapy + antiEGFR.

PATIENTS AND METHODS

The COLT trial is an investigator-driven, multicenter, non-randomized, open-label, controlled, prospective, parallel trial (ClinicalTrials.gov NCT03803436). Hyperselected patients with liver-limited unresectable CLM, RAS and BRAF wild-type and curatively removed primary colon cancer are included. The observed post-transplant outcomes will be prospectively compared 1:5 with those obtained in a matched cohort from the TRIPLETE trial (NCT03231722).

RESULTS

Primary endpoint is to compare the 3 and 5-years OS of patients enrolled in the COLT trial with COLT-eligible population enrolled in the TRIPLETE trial. An expected gain in OS of 40% at 5-years is predicted for the COLT population (the expected OS at 5-years in COLT vs. TRIPLETE is 70% vs. 30%). Secondary endpoints are to compare the 5-years disease-free survival and to assess the safety of LT (Dindo-Clavien Classification and the Comprehensive Complication Index).

CONCLUSION

LT offers the longest OS reported in selected patients with CLM. Improving the selection strategies can give patients a 5-year OS similar to other indications for LT and a better outcome than those undergoing chemotherapy alone.

The Liver Tumor Segmentation Benchmark (LiTS)

In this work, we report the set-up and results of the Liver Tumor Segmentation Benchmark (LiTS), which was organized in conjunction with the IEEE International Symposium on Biomedical Imaging (ISBI) 2017 and the International Conferences on Medical Image Computing and Computer-Assisted Intervention (MICCAI) 2017 and 2018. The image dataset is diverse and contains primary and secondary tumors with varied sizes and appearances with various lesion-to-background levels (hyper-/hypo-dense), created in collaboration with seven hospitals and research institutions. Seventy-five submitted liver and liver tumor segmentation algorithms were trained on a set of 131 computed tomography (CT) volumes and were tested on 70 unseen test images acquired from different patients. We found that not a single algorithm performed best for both liver and liver tumors in the three events. The best liver segmentation algorithm achieved a Dice score of 0.963, whereas, for tumor segmentation, the best algorithms achieved Dices scores of 0.674 (ISBI 2017), 0.702 (MICCAI 2017), and 0.739 (MICCAI 2018). Retrospectively, we performed additional analysis on liver tumor detection and revealed that not all top-performing segmentation algorithms worked well for tumor detection. The best liver tumor detection method achieved a lesion-wise recall of 0.458 (ISBI 2017), 0.515 (MICCAI 2017), and 0.554 (MICCAI 2018), indicating the need for further research. LiTS remains an active benchmark and resource for research, e.g., contributing the liver-related segmentation tasks in http://medicaldecathlon.com/. In addition, both data and online evaluation are accessible via https://competitions.codalab.org/competitions/17094.

Primary hepatic myopericytoma coexisting with multiple cystic hepatic lesions: a case report

BACKGROUND

Hepatic myopericytoma (MPC) is an extremely rare pathological entity in the liver. Conversely, cystic hepatic lesions are a group of heterogeneous lesions encountered commonly in daily practice. Here, we report a unique case of the coexistence of primary hepatic MPC and multiple cystic hepatic lesions along with our perceptions on its diagnosis and treatment.

CASE PRESENTATION

A 56-year-old female patient was found to have a left liver mass during a routine physical examination. Computer tomography (CT) and magnetic resonance imaging (MRI) confirmed the existence of a left hepatic neoplasm along with multiple hepatic cysts but could not exclude the possible malignant nature of the neoplasm. Computer tomography (CT) also identified an enlarged mediastinal lymph node with a maximum diameter of 4.3 cm, which further underwent core needle biopsy under CT guidance. A histopathological examination was performed to rule out malignancy. Afterwards, the patient underwent left hemihepatectomy to resect a solid tumor of 5.5 cm × 5 cm × 4.7 cm with multiple cystic lesions which were histopathologically examined to establish the diagnosis of myopericytoma with hepatic cysts. Postoperatively, the patient recovered from the surgery quickly without significant adverse events and was not found to have a reoccurrence of the primary pathological entity.

CONCLUSIONS

This is the first reported case of a patient with the co-existence of primary hepatic myopericytoma and multiple cystic hepatic lesions undergoing surgical treatment with eventual recovery.

Estimation of post-therapeutic liver reserve capacity using 99mTc-GSA scintigraphy prior to carbon-ion radiotherapy for liver tumors

BACKGROUND

There is currently no established imaging method for assessing liver reserve capacity prior to carbon-ion radiotherapy (CIRT) for liver tumors. In order to perform safe CIRT, it is essential to estimate the post-therapeutic residual reserve capacity of the liver.

PURPOSE

To evaluate the ability of pre-treatment 99mTc-galactosyl human serum albumin (99mTc-GSA) scintigraphy to accurately estimate the residual liver reserve capacity in patients treated with CIRT for liver tumors.

MATERIALS AND METHODS

This retrospective study evaluated patients who were performed CIRT for liver tumors between December 2018 and September 2020 and underwent 99mTc-GSA scintigraphy before and 3 months after CIRT, and gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MRI within 1 month before CIRT were evaluated. The maximal removal rate of 99mTc-GSA (GSA-Rmax) was analyzed for the evaluation of pre-treatment liver reserve capacity. Then, the GSA-Rmax of the estimated residual liver (GSA-RL) was calculated using liver SPECT images fused with the Gd-EOB-DTPA-enhanced MRI. GSA-RL before CIRT and GSA-Rmax at 3 months after CIRT were compared using non-parametric Wilcoxon signed-rank test and linear regression analysis.

RESULTS

Overall, 50 patients were included (mean age ± standard deviation, 73 years ± 11; range, 29-89 years, 35 men). The median GSA-RL was 0.393 [range, 0.057-0.729] mg/min, and the median GSA-Rmax after CIRT was 0.369 [range, 0.037-0.780] mg/min (P = .40). The linear regression equation representing the relationship between the GSA-RL and GSA-Rmax after CIRT was y = 0.05 + 0.84x (R2 = 0.67, P < .0001). There was a linear relationship between the estimated and actual post-treatment values for all patients, as well as in the group with impaired liver reserve capacity (y = - 0.02 + 1.09x (R2 = 0.62, P = .0005)).

CONCLUSIONS

99mTc-GSA scintigraphy has potential clinical utility for estimating the residual liver reserve capacity in patients undergoing carbon-ion radiotherapy for liver tumors.

TRIAL REGISTRATION

UMIN000038328, https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000043545 .

Multitargeting Strategy Using Tetrathiomolybdate and Lenvatinib: Maximizing Antiangiogenesis Activity in a Preclinical Liver Cancer Model

PURPOSE

The study aims to investigate the suppressing tumor-promoting effects via multi-anti-angiogenesis activity of the copper chelator (ammonium tetrathiomolybdate, TM) combined with lenvatinib for hepatocellular carcinoma.

METHODS

A total of 55 C57 mice were injected subcutaneously with Hepa1-6 hepatoma cell suspensions into the right posterior thigh. After 7 days, the subcutaneous tumors were formed, and the mice were randomly divided into five groups: TM (G1), Lenvatinib (G2), TM+Lenvatinib (G3), Control (G4), and Copper (II) Gluconate (G5). The copper concentrations in serum and tumors were measured at the predetermined time points. After 14 days of treatments, tumor weight and volumes were analyzed, histology was observed, and the expressions of vascular endothelial growth factor (VEGF) and microvessel density (MVD) in tumor tissues were measured by immunohistochemistry.

RESULTS

The median concentration of copper in serum was 401.70, 469.40, and 665.35 μg/L in normal mice, in mice 7 days after implantation, and in the control group, respectively. The intratumoral copper concentrations were higher in G4 mice than in mice 7 days after implantation (P < 0.05). The serum concentration of copper was higher in G5 than all the other groups (P < 0.05; (G1, G2, and G3) vs. G4, P < 0.05; G1 vs. G2, P = 0.013; G2 vs. G3, P = 0.018; G1 vs. G3, P = 0.903. The intratumoral copper concentrations were 608.40, 980.00, 539.31, and 2938.90 μg/L in G1, G2, G3, and G5, respectively. The average tumor weight was 0.55, 0.44, 0.08, 1.37, and 3.11 in G1, G2, G3, G4, and G5, respectively. G5 vs. other groups, P < 0.05; (G1, G2, and G3) vs. G4, P < 0.05; G1 vs. G3, P < 0.05; G2 vs. G3, P < 0.05; G1 vs. G2, P > 0.05. Furthermore, the expression levels of VEGF were significantly lower in G1, G2, and G3 than in G4 and G5 (P < 0.05). A similar trend was observed for MVD in the five groups, but no significant difference was detected in G1 and G2.

CONCLUSION

The study showed a significant positive correlation between tumor load and copper. Copper promotes tumor progression, but copper chelating suppresses tumor growth. The combination of TM with lenvatinib reduces tumor angiogenesis and improves the effect of antitumor treatment. These findings underlie the clinical application of combination therapy.

Can living donor liver transplantation provide similar outcomes to deceased-donor liver transplantation for hepatocellular carcinoma? A systematic review and meta-analysis

BACKGROUND AND AIM

A potential solution to the deceased organ shortage is to include live organ donations and to identify patients with lower rates of HCC recurrence to fairly allocate liver grafts. Our aims were to detect the long-term outcomes of LDLT versus DDLT for HCC and predictors of recurrence after transplantation.

METHODS

PubMed, Scopus, Web of Science, Cochrane library were searched for eligible studies from inception to July 2021 and a systematic review and meta-analysis were done.

RESULTS

35 studies with a total of 7822 patients were included. The 1-, 3-, 4 year-OS showed trivial improvement for LDLT recipients. However, the two modalities had similar 5-, 6- and 10-year OS. A significant improvement in the ITT-OS was observed for LDLT recipients. Regarding the DFS and recurrence after transplantation, no significant difference was observed between LDLT and DDLT. In addition to that, the pooled hazard ratio of the included studies showed that Milan criteria, level of AFP, presence of vascular invasion, tumor differentiation were significant predictors of recurrence.

CONCLUSION

The cancer biology (not the graft type) is the most important determinant of recurrence and survival after LT. However, LDLT provided much better survival benefits to HCC patients especially in regions that suffer from low deceased organ availability.

A study of the clinical profile, predictors, prognostic features, and survival of patients with hepatocellular carcinoma having macroscopic portal vein tumor thrombosis

BACKGROUND

Macroscopic portal vein tumor thrombosis (PVTT) is considered a negative prognostic factor in hepatocellular carcinoma (HCC) patients. There is divergent opinion regarding management of these patients worldwide. We aimed to evaluate the clinical profile, predictors, prognostic features, and survival of patients of HCC with PVTT.

METHODS

Treatment-naïve HCC patients with and without PVTT were analyzed retrospectively using a prospectively accrued dataset. Patients with PVTT were further divided as per treatment groups for survival analysis.

RESULTS

Of 508 patients, 46.1% had radiological evidence of PVTT at presentation. On logistic regression, serum albumin (odds ratio [OR]=0.65, 95% confidence interval [CI]= 0.44-0.96; p= 0.031); international normalized ratio (OR = 3.78,95% CI = 1.42-10.00; p=0.008); alpha-feto protein >400 ng/mL (OR=3.58, 95%CI = 2.00-6.40; p <0.001); size of largest tumor nodule >5 cm (OR =6.37, 95%CI =2.03-19.99; p =0.002); and male gender (OR =1.84, 95%CI = 1.01-3.33; p = 0.045) were independent predictors for PVTT. Patients with PVTT amenable to aggressive therapies had significantly better median overall survival (in months) as compared to those receiving sorafenib or best supportive care only (13.1, 3.9, and 1.8 respectively, p<0.0001). Treatment modality received (p<0.001) and extrahepatic metastasis (p=0.006) were independent predictors of mortality in these patients.

CONCLUSION

Size of largest tumor nodule >5 cm and alpha-fetoprotein >400 ng/mL are strongly associated with the presence of PVTT in patients with HCC. A multidisciplinary approach may identify a subgroup of patients who can be offered aggressive therapies like surgery and/or locoregional therapy with significant survival benefit.

Prevention of major biliary complications by fusion imaging for thermal ablation of malignant liver tumors adjacent to the bile ducts: a preliminary comparative study

PURPOSE

Ultrasound (US)-guided thermal ablation (TA) may cause major biliary complications, particularly in patients with malignant liver tumors (MLTs) adjacent to the bile ducts. Fusion imaging (FI), is postulated to reduce complication rate; however, there is a lack of clinical data to support this theory. Thus, the aim of our study was to evaluate the safety and efficacy of FI for TA of MLTs proximal to the bile ducts.

METHODS

A retrospective single-center review was conducted on a total of 289 patients with 316 MLTs adjacent to the bile ducts. The patients were divided into two groups based on whether FI was used in the ablation procedures. The choice of the FI-assisted procedure always depends on different operation periods and whether registrations will succeed. The baseline demographics and outcomes of these patients were compared. The efficacy was determined at the 1-month follow-up using contrast-enhanced computed tomography/magnetic resonance. Biliary complications and local tumor progression were subsequently followed-up every 3-6 months. The last follow-up visit was before August 30, 2019.

RESULTS

Among the included tumors, the incidence rate of major biliary complications after ablation in the FI group was 1.6%, which was significantly lower than that in the non-FI group (7.9%, p = 0.005). There was no significant difference in the efficacy rates of the techniques [99.5% (185/186) versus 98.4% (123/125), p = 0.56] or local progression rates [3.8% (7/185) versus 5.7% (7/123), p = 0.61] between the FI and non-FI groups.

CONCLUSION

FI for US-guided TA could be a noninvasive means to decrease major biliary complications. Trial registration number and date of registration: retrospectively registered.

Minimally invasive versus open hepatectomy for the resection of colorectal liver metastases: a systematic review and meta-analysis

BACKGROUND

While surgical resection has a demonstrated utility for patients with colorectal liver metastases (CRLM), it is unclear whether minimally invasive surgery (MIS) or an open approach should be used. This review sought to assess the efficacy and safety of MIS versus open hepatectomy for isolated, resectable CRLM when performed separately from (Key Question (KQ) 1) or simultaneously with (KQ2) the resection of the primary tumor.

METHODS

PubMed, Embase, Google Scholar, Cochrane CENTRAL, International Clinical Trials Registry Platform (ICTRP), and ClinicalTrials.gov databases were searched to identify both randomized controlled trials (RCTs) and non-randomized comparative studies published during January 2000-September 2020. Two independent reviewers screened literature for eligibility, extracted data from included studies, and assessed internal validity using the Cochrane Risk of Bias 2.0 Tool and the Newcastle-Ottawa Scale. A random-effects meta-analysis was performed using risk ratios (RR) and mean differences (MD).

RESULTS

From 2304 publications, 35 studies were included for meta-analysis. For staged resections, three RCTs and 20 observational studies were included. Data from RCTs indicated MIS having similar disease-free survival (DFS) at 1-year (RR 1.03, 95%CI 0.70-1.50), overall survival (OS) at 5-years (RR 1.04, 95%CI 0.84-1.28), fewer complications of Clavien-Dindo Grade III (RR 0.62, 95%CI 0.38-1.00), and shorter hospital length of stay (LOS) (MD -6.6 days, 95%CI -10.2, -3.0). For simultaneous resections, 12 observational studies were included. There was no evidence of a difference between MIS and the open group for DFS-1-year, OS-5-year, complications, R0 resections, blood transfusions, along with lower blood loss (MD -177.35 mL, 95%CI -273.17, -81.53) and shorter LOS (MD -3.0 days, 95%CI -3.82, -2.17).

CONCLUSIONS

Current evidence regarding the optimal approach for CRLM resection demonstrates similar oncologic outcomes between MIS and open techniques, however MIS hepatectomy had a shorter LOS, lower blood loss and complication rate, for both staged and simultaneous resections.

Suitability of Laparoscopic Liver Resection of Segment VII: a Retrospective Two-Center Study

BACKGROUND

Resecting liver tumors located in Couinaud's segment VII is challenging; the efficacy and safety of laparoscopic liver resection for segment VII lesions compared to open liver resection remain unclear.

METHODS

Medical records of 84 patients who underwent liver resection of segment VII at Kobe University Hospital and Hyogo Cancer Center between 2010 and 2021 were retrospectively analyzed. Surgical outcomes were compared between laparoscopic liver resection and open liver resection groups using propensity matching analysis.

RESULTS

Thirty-one and 53 patients underwent laparoscopic liver resection and open liver resection, respectively. After propensity matching, 29 patients were included in each group. The laparoscopic liver resection group had a significantly longer operation time (407 vs. 305 min, P = 0.002), lower blood loss (100 vs. 230 mL, P = 0.004), and higher postoperative alanine aminotransferase levels (436 vs. 252 IU/L, P = 0.008) than the open liver resection group. In patients with liver cirrhosis, the proportion of patients with postoperative liver-specific complications was higher in the laparoscopic liver resection group than in the open liver resection group (57% vs 11%, P = 0.049), although there was no significant difference in postoperative liver-specific complication rates between the groups in patients without liver cirrhosis.

CONCLUSIONS

For liver resection of segment VII, laparoscopic liver resection led to higher postoperative liver damage than open liver resection. Open liver resection may be better for patients with liver cirrhosis to avoid postoperative liver-specific complications. Laparoscopic liver resection could be an acceptable procedure for patients without liver cirrhosis, with some merits such as less blood loss.

Two Cases of Hepatoblastoma in Adults

Adult hepatoblastoma is a rare tumor whose etiology and mechanisms of development are still incompletely understood. Imaging and biological tests such as AFP and liver enzymes are non-specific. Histologically, there are 2 histological variants: pure epithelial with 5 types (pure fetal, embryonal, small cell undifferentiated, cholangioblastic, and macrotrabecular), a mixed epithelial and a mesenchymal variant with or without a teratoid contingent. The main differential diagnosis concerns hepatocellular carcinoma. The treatment of hepatoblastoma in adults is not yet standardized and surgery remains the mainstay of treatment. In this report we aim to describe the clinical, pathological, and immunohistochemical features of this rare entity in adult patients and discuss the elements allowing its distinction from hepatocellular carcinoma (HCC).

Hepatic Deletion of X-box Binding Protein 1 in Farnesoid X Receptor Null Mice Leads to Enhanced Liver Injury

Farnesoid X receptor (FXR) regulates bile acid metabolism, and FXR null (Fxr^-/-) mice have elevated bile acid levels and progressive liver injury. The inositol-requiring enzyme 1α (IRE1α)/X-box binding protein 1 (XBP1) pathway is a protective unfolded protein response (UPR) pathway activated in response to ER stress. Here, we sought to determine the role of the IRE1α/XBP1 pathway in hepatic bile acid toxicity using the Fxr^-/- mouse model. Western blotting and qPCR analysis demonstrated that hepatic XBP1 and other UPR pathways were activated in 24-week-old Fxr^-/- compared to 10-week-old Fxr^-/- mice, but not in WT mice. To further determine the role of the liver XBP1 activation in older Fxr^-/- mice, we generated mice with whole-body FXR and liver-specific XBP1 double knockout (DKO, Fxr^-/-Xbp1^LKO) and Fxr^-/-Xbp1^fl/fl single knockout (SKO) mice and characterized the role of hepatic XBP1 in cholestatic liver injury. Histologic staining demonstrated increased liver injury and fibrosis in DKO compared to SKO mice. RNA-seq revealed increased gene expression in apoptosis, inflammation, and cell proliferation pathways in DKO mice. The proapoptotic C/EBP-homologous protein (CHOP) pathway and cell cycle marker Cyclin D1 were also activated in DKO mice. Furthermore, we found total hepatic bile acid levels were similar between the two genotypes. At age 60 weeks, all DKO mice and no SKO mice spontaneously developed liver tumors. In conclusion, the hepatic XBP1 pathway is activated in older Fxr^-/- mice and has a protective role. The potential interaction between XBP1 and FXR signaling may be important in modulating the hepatocellular cholestatic stress responses.

Safety of CT-Guided Microwave Ablation of Subcardiac Liver Tumors

PURPOSE

The purpose of this study was to investigate the safety of CT-guided microwave ablation (MWA) of subcardiac hepatic tumors.

MATERIALS AND METHODS

This retrospective study included 19 patients (11 males and 8 females, age: 64.0 years (IQR: 58.3, 71.0) who underwent CT-guided MWA of 22 subcardiac tumors from January 2016 through December 2020. The subcardiac tumors consisted of 6 hepatocellular carcinomas and 16 metastases. Hydrodissection or other thermal protection technique was not used during the ablation. Subcardiac ablation was defined as the ablation zone extended ≤ 0.5 cm from myocardium or coronary artery. The safety of MWA of subcardiac tumors was evaluated based on procedural and post-procedural complications and intra-procedural ECG changes. Local tumor progression (LTP) was also analyzed and correlated with tumor and ablation zone sizes.

RESULTS

The primary efficacy rate was 100%. The median follow-up was 20.5 months (IQR: 6.0, 29.8). There was no 30-day mortality. One grade 3 complication occurred (severe shoulder and chest pain), and there were 19 events of grade 1 or 2 complications. No instances of cardiac complications or significant procedural ECG changes were observed. There were 22 events of grade 1 and 2 laboratory toxicity and 1 event of grade 3 elevated bilirubin. The LTP was 13.6% at 1 year and 22.7% at 2 years. There was no significant correlation between LTP and tumor or ablation zone sizes.

CONCLUSION

CT-guided MWA of subcardiac hepatic tumors is safe, and MWA should be considered as an option for managing subcardiac tumors. LTP rates for MWA of subcardiac tumors may be inferior to ablation of tumors in common location.

LEVEL OF EVIDENCE III

Cohort Study.

Integration of a dedicated management protocol in the care of pediatric liver cancer: From specialized providers to complication reduction

INTRODUCTION

Up to a third of children undergoing partial hepatectomy for primary hepatic malignancies experience at least one perioperative complication, with a presumed deleterious effect on both short- and long-term outcomes. We implemented a multidisciplinary treatment protocol in the management of these patients in order to improve complication rates following partial hepatectomy.

METHODS

A retrospective chart review was completed for all patients < 18 years of age who underwent liver resection at our institution between 2002 and 2019 for primary hepatic cancer. Demographic, intraoperative, postoperative, pathologic, and outcome data were analyzed for perioperative complications using the CLASSIC and Clavien-Dindo (CD) scales, event-free survival (EFS) and overall survival (OS).

RESULTS

A total of 73 patients were included in the analysis with 33 prior-to and 40 after dedicated provider protocol implementation. Perioperative complication rates decreased from 52% to 20% (p = 0.005) with major complications going from 18% to 10% (p = 0.31). On multivariable logistic regression, protocol implementation was associated with a reduction in any (OR 0.29 [95% CI 0.09 - 0.89]) but not major complications. On multivariate cox models, post protocol implementation was associated with improved event free survival (EFS) (HR 0.19 (0.036 - 0.195). Among patients with a diagnosis of hepatoblastoma (n = 62), the occurrence of a major perioperative complication was associated with a worse EFS (HR=5.45, p = 0.03) on multivariate analysis, however this did not translate into an impact on overall survival.

CONCLUSIONS

Our results demonstrate that, for children with primary liver malignancies, a dedication of patients to high-volume surgeons can improve rates of complications of liver resections and may improve the oncological outcome of hepatoblastoma.

A comparative study on computational models of multi-electrode radiofrequency ablation of large liver tumors

PURPOSE

Thermal ablation of liver tumors has emerged as a first-line curative treatment for single small tumors (diameter < 2.5 cm) due to similar overall survival rates as surgical resection. Moreover, it is far less invasive, has lower complication rates, a superior cost-effectiveness, and an extremely low treatment-associated mortality. However, in many cases, complete tumor coverage cannot be achieved only with a single electrode and several electrodes are used to create overlapping ablations. Multi-electrode planning is a challenging 3D task with many contradictive constraints to consider, a dimensionality difficult to assess even for experts. It requires extremely long planning time since it is mostly performed mentally by clinicians looking at 2D CT views. An accurate and reliable prediction of the ablation zone would help to turn thermal ablation into a first-line curative treatment also for large liver tumors treated with multiple electrodes. In order to determine the level of model simplification that can be acceptable, we compared three computational models, a simple spherical model, a biophysics-based model and an Eikonal model.

METHODS

RF ablation electrodes were virtually placed at a desired position in the patient pre-operative CT image and the models predicted the ablation zone generated by multiple electrodes. The last two models are patient-specific. In these cases, hepatic structures were automatically segmented from the pre-operative CT images to predict a patient-specific ablation zone.

RESULTS

The three models were used to simulate multiple electrode ablations on 12 large tumors from 11 patients for which the procedure information was available. Biophysics-based simulations approximate better the post-operative ablation zone in term of Hausdorff distance, Dice Similarity Coefficient, radius, and volume compared to two other methods. It also predicts better the coverage percentage and thus the tumor ablation margin.

CONCLUSION

The results obtained with the biophysics-based model indicate that it could improve ablation planning by accurately predicting the ablation zone, avoiding over or under-treatment. This is particularly beneficial for multi-electrode radiofrequency ablation of larger liver tumors where the planning phase is particularly challenging.

The study of direct and indirect effects of radiofrequency ablation on tumor microenvironment in liver tumor animal model

Background

Direct and indirect effects of radiofrequency ablation (RFA) on tumor microenvironment of the liver tumor have been noted, which was reported to be related to a variety of tyrosine protein kinase or cytokinetic pathway, but have not been thoroughly investigated and conclusive.

Purpose

To elucidate direct and indirect effects of RFA on tumor microenvironment in the liver tumor model, and to explore the role of the specific inhibitor in tumor growth by targeting the key pathway of RFA.

Materials and methods

One hundred and ten mice with H22 liver tumor were used in animal experiments. Eighty-four mice were randomized into three groups: control, direct RFA and indirect RFA (a block slide was inside the middle of the tumor). The growth rate of the residual tumor after RFA was calculated (n = 8 each group) and the pathologic changes at different time points (6 h, 24 h, 72 h and 7d after RFA) were evaluated (n = 5 in each subgroup). After semi-quantitative analysis of the pathological staining, the most significant marker after RFA was selected. Then, the specific inhibitor (PHA) was applied with RFA and the tumor growth and pathological changes were evaluated and compared with RFA alone. The Kruskal-Wallis test was used for evaluating the significance of different treatments in the pathological positive rate of specific markers in tumor. The two-way analysis of variance was used to determine the significance of treatment in tumor growth or body weight.

Results

The growth rate of the residual tumor in the direct RFA group was faster than the indirect RFA group (P = 0.026). The pathological analysis showed the expression of HSP70 (73 ± 13% vs 27 ± 9% at 24 h, P < 0.001), SMA (70 ± 18% vs 18 ± 7% at 6 h, P < 0.001) and Ki-67 (51 ± 11% vs 33 ± 14% at 7d, P < 0.001) in the direct RFA group was higher than those in the indirect RFA group after RFA. On the other hand, the expression of c-Met (38 ± 11% vs 28 ± 9% at 24 h, P = 0.01), IL-6 (41 ± 10% vs 25 ± 9% at 24 h, P < 0.001) and HIF-α (48 ± 10% vs 28 ± 8% at 24 h, P < 0.001) in the indirect RFA group was higher than those in the direct RFA group. And the expression of c-Met increased mostly in both direct and indirect RFA group compared to the baseline (53 and 65% at 72 h). Then the specific inhibitor of c-Met-PHA was applied with RFA. The growth rate of the tumor was significantly slower in the RFA + PHA group than the RFA alone group (1112.9 ± 465.6 mm³ vs 2162.7 ± 911.1 mm³ at day 16, P = 0.02).

Conclusion

Direct and indirect effects of RFA on tumor microenvironment changed at different time points and resulted in increased residual tumor growth in the animal model. It can be potentially neutralized with specific inhibitor of related pathways, such as tyrosine-protein kinase c-Met.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09730-x.

Classification of hepatic cavernous hemangioma or hepatocellular carcinoma using a convolutional neural network model

BACKGROUND

Computed tomography (CT) is a common imaging technique for diagnosis of liver tumors. However, the intensity similarity on non-contrast CT images is small, making it difficult for radiologists to visually identify hepatic cavernous hemangioma (HCH) and hepatocellular carcinoma (HCC). Recently, convolutional neural networks (CNN) have been widely used in the study of medical image classification because more discriminative image features can be extracted than the human eye. Therefore, this study focused on developing a CNN model for identifying HCH and HCC.

METHODS

This study is a retrospective study. A dataset consisting of 774 non-contrast CT images was collected from 50 patients with HCC or HCH, and the ground truth was given by three radiologists based on contrast-enhanced CT. Firstly, the non-contrast CT images dataset were randomly divided into a training set (n=559) and a test set (n=215). Then, we performed preprocessing of the non-contrast CT images using pseudo-color conversion, and the proposed CNN model developed using training set. Finally, the following indicators (accuracy, precision, recall) were used to quantitatively analyze the results.

RESULTS

In the test set, the proposed CNN model achieved a high classification accuracy of 84.25%, precision of 81.36%, and recall of 82.18%.

CONCLUSIONS

The CNN model for identifying HCH and HCC improves the accuracy of diagnosis on non-contrast CT images.

Isolated complete caudate lobectomy with Glissonean pedicle isolation using Takasaki's technique and right-left approach: preliminary experience from two case reports

Background

Tumors located in the caudate lobe may be primary tumor or metastases from other sites. Isolated caudate lobectomy (ICL) is a challenging procedure due to its complex structure and location. The access route to the caudate lobe has an important role in the success of the operation.

Methods

Based on the characteristics of the segment I location, which is the part of the liver located in front of the vena cava, below the hepatic veins, and cranial to the hilar plate, our approach aims to isolate the entire caudate lobe from these anatomical structures with the following steps: dissecting the caudate lobe from the hilar plate and isolating the caudate lobe from the IVC and from the hepatic veins along with parenchymal resection.

Results

We report two successful cases with the Glissonean pedicle transection method described by Takasaki and the combined right- and left-side approach: a 63-year-old female patient with a 46-mm-in-diameter HCC tumor and a 39-year-old female patient with a 45-mm lesion and the pathological result was focal nodular hyperplasia.

Conclusions

We found this to be a safe and effective approach, which can be applied to all cases of benign tumors or in the case of malignant tumors located entirely in the caudate lobe when extended hepatic resection is not possible due to poor liver function or small remnant liver volume.

First Report of a Late Lethal Pulmonary Biliary Embolism following Hepatic Microwave Ablation

Microwave ablation (MWA) is an established tool in modern therapy of hepatic malignomas. Although it is generally a safe procedure, severe complications related to MWA have been reported in the literature. We report on the first case of a fatal pulmonary biliary embolism following hepatic MWA. The development of pulmonary biliary embolisms is possible and should be considered particularly in the case of by extensive ablation near liver veins.

Artificial intelligence (AI) models for the ultrasonographic diagnosis of liver tumors and comparison of diagnostic accuracies between AI and human experts

BACKGROUND

Ultrasonography (US) is widely used for the diagnosis of liver tumors. However, the accuracy of the diagnosis largely depends on the visual perception of humans. Hence, we aimed to construct artificial intelligence (AI) models for the diagnosis of liver tumors in US.

METHODS

We constructed three AI models based on still B-mode images: model-1 using 24,675 images, model-2 using 57,145 images, and model-3 using 70,950 images. A convolutional neural network was used to train the US images. The four-class liver tumor discrimination by AI, namely, cysts, hemangiomas, hepatocellular carcinoma, and metastatic tumors, was examined. The accuracy of the AI diagnosis was evaluated using tenfold cross-validation. The diagnostic performances of the AI models and human experts were also compared using an independent test cohort of video images.

RESULTS

The diagnostic accuracies of model-1, model-2, and model-3 in the four tumor types are 86.8%, 91.0%, and 91.1%, whereas those for malignant tumor are 91.3%, 94.3%, and 94.3%, respectively. In the independent comparison of the AIs and physicians, the percentages of correct diagnoses (accuracies) by the AIs are 80.0%, 81.8%, and 89.1% in model-1, model-2, and model-3, respectively. Meanwhile, the median percentages of correct diagnoses are 67.3% (range 63.6%-69.1%) and 47.3% (45.5%-47.3%) by human experts and non-experts, respectively.

CONCLUSION

The performance of the AI models surpassed that of human experts in the four-class discrimination and benign and malignant discrimination of liver tumors. Thus, the AI models can help prevent human errors in US diagnosis.

Role of endoscopic ultrasound in the field of hepatology: Recent advances and future trends

The role of endoscopic ultrasound (EUS) as a diagnostic and therapeutic modality for the management of various gastrointestinal diseases has been expanding. The imaging or intervention for various liver diseases has primarily been the domain of radiologists. With the advances in EUS, the domain of endosonologists is rapidly expanding in the field of hepatology. The ability to combine endoscopy and sonography in one hybrid device is a unique property of EUS, together with the ability to bring its probe/transducer near the liver, the area of interest. Its excellent spatial resolution and ability to provide real-time images coupled with several enhancement techniques, such as contrast-enhanced (CE) EUS, have facilitated the growth of EUS. The concept of “Endo-hepatology” encompasses the wide range of diagnostic and therapeutic procedures that are now gradually becoming feasible for managing various liver diseases. Diagnostic advancements can enable a wide array of techniques from elastography and liver biopsy for liver parenchymal diseases, to CE-EUS for focal liver lesions to portal pressure measurements for managing various liver conditions. Similarly, therapeutic advancements range from EUS-guided eradication of varices, drainage of bilomas and abscesses to various EUS-guided modalities of liver tumor management. We provide a comprehensive review of all the different diagnostic and therapeutic EUS modalities available for the management of various liver diseases. A synopsis of all the technical details involving each procedure and the available data has been tabulated, and the future trends in this area have been highlighted.

Liver tumors in children with chronic liver diseases

Liver tumors are rare in children, but the incidence may increase in some circumstances and particularly in chronic liver diseases. Most liver tumors consequent to chronic liver diseases are malignant hepatocellular carcinoma. Other liver tumors include hepatoblastoma, focal nodular hyperplasia, adenoma, pseudotumor, and nodular regenerative hyperplasia. Screening of suspected cases is beneficial. Imaging and surrogate markers of alpha-fetoprotein are used initially as noninvasive tools for surveillance. However, liver biopsy for histopathology evaluation might be necessary for patients with inconclusive findings. Once the malignant liver tumor is detected in children with cirrhosis, liver transplantation is currently considered the preferred option and achieves favorable outcomes. Based on the current evidence, this review focuses on liver tumors with underlying chronic liver disease, their epidemiology, pathogenesis, early recognition, and effective management.

Huge solitary necrotic nodule of the liver: a rare case report with review of literature

Solitary necrotic nodule of the liver (SNNL) is an uncommon disease in clinical practice, and its pathogenesis is still unclear. Here, we report the case of a 35-year-old woman. After physical examination, the patient was found to have a liver neoplasm, and there were no other physical complaints. Abdominal contrast-enhanced computed tomography (CT) showed the presence of a hypodense lesion. The patient opted for surgery to eliminate the lesion. Pathologic examination revealed an isolated necrotic nodular lesion with a size of 12 cm×10 cm×10 cm. The patient had a history of hepatitis B infection. To our knowledge, this is the largest SNNL ever reported and the first case with a history of hepatitis B infection.

Applying criteria for hepatocellular neoplasm of uncertain malignant potential reclassifies more than half of hepatocellular adenomas

OBJECTIVES

Hepatocellular adenoma (HCA) is a benign well-differentiated hepatocellular neoplasm that can be difficult to distinguish from well-differentiated hepatocellular carcinoma (HCC). The term "well-differentiated hepatocellular neoplasm of uncertain malignant potential" (HUMP) has been proposed for neoplasms resembling HCAs, but arising in atypical clinical situations (in females over 50 years old or under 15, in males, with anabolic steroid use, or in some congenital conditions), and/or with atypical pathological features (focal cytological/architectural atypia, β-catenin activation, or focal reticulin loss) insufficient for an unequivocal diagnosis of HCC.

METHODS

This study evaluated HUMP criteria on 42 previously diagnosed HCAs from 33 patients.

RESULTS

Twenty-six (62%) masses from 21 patients were classified as HUMPs. Eleven (42%) had focal cytological atypia, and two (8%) had focal architectural atypia. Four (15%) showed focal reticulin loss. Five (19%) showed evidence of β-catenin activation. Four (12%) HUMP patients were male.

CONCLUSIONS

In this series, HUMP did not correlate with an increased rate of synchronous or metachronous HCC compared to HCA. Clinical colleagues may not accept such a high rate of tumors placed in a category of "uncertain malignant potential". Additional study is warranted to refine criteria for designating well-differentiated hepatocellular neoplasms as of uncertain malignant potential.