Modified median hepatic fissure approach for resection of liver tumours located in the angle between the root of the middle and right hepatic veins

Background Liver tumours between the root angle of the middle and right hepatic veins are a special type of liver segment VIII tumour. In this study, we designed a modified median hepatic fissure approach to remove these tumours. The safety and effectiveness of the approach were evaluated. Materials and methods From April 2015 to November 2019, 11 patients with liver tumours between the angle of the middle and right hepatic veins underwent this modified median hepatic fissure approach. We retrospectively analysed data from the perioperative periods of these 11 patients, including general condition, operation time, intraoperative bleeding, and postoperative complications. Disease-free survival and overall survival were assessed. Results Of the 11 patients, 9 patients had primary hepatocellular carcinoma and 2 had colorectal liver metastases. The average intraoperative blood loss was 285 mL (150–450 mL). Two patients developed postoperative bile leakage, but there were no significant serious complications, such as intraabdominal bleeding and liver failure, in any of the patients. The liver function returned to the normal range on the 5th day after surgery. Of the 11 patients, 5 have survived for more than 3 years (45.5%), and 4 have been disease-free for more than 3 years (36.3%). Conclusions For liver tumours between the root angle of the middle and right hepatic veins, the modified median hepatic fissure approach is a safe and feasible method.

Diagnostic performance of total-body 18F-FDG PET/CT with fast 2-min acquisition for liver tumours: Comparison with conventional PET/CT

PurposeTo comparatively evaluate the diagnostic performances of total-body 18F-FDG PET/CT with fast 2-min acquisition and conventional PET/CT in liver cancer patients.Methods This study included 156 patients with liver tumours. Seventy-eight patients underwent total-body PET/CT. PET raw data were reconstructed using acquisition durations of 2 min (G2) and 15 min (G15). Another 78 patients with liver lesions (control patients) underwent conventional uMI780 PET/CT (G780). All patients were evaluated based on TNM staging. The maximum tumour standardized uptake value (tumour SUVmax), mean normal liver SUV (SUVmean), and tumour SUVmax-to-liver SUVmean ratio (TLR) were determined for all patients. G15 data were used as the reference in the lesion detectability analysis. The diagnostic performances of PET/CT in terms of visual parameters and of PET in terms of semi-quantitative parameters such as SUVmax and TLR were evaluated. Receiver operating characteristics (ROC) curve analysis of SUVmax and TLR at G2 was performed. Pathologic findings of surgical specimens served as the gold standard for all patients.Results The lesions found in G15 were also noted in G2; three lymph nodes were missed in G2; however, no significant difference was found in the TNM stage among G2, G15, and G780. For benign and malignant lesions, the liver SUVmean in G2 and G15 was higher than that in G780 (all P < 0.05). The tumour SUVmax and TLR in G2 were equivalent to those in G15 and G780 regardless of whether the lesions were benign or malignant. ROC curve analysis (SUVmax cut-off: 4.34, TLR cut-off: 1.34) demonstrated that G2 also had good sensitivity in detecting liver cancer. Conclusion The diagnostic performance of total-body PET/CT in G2 was comparable to that in G15 among liver cancer patients. Further, the diagnostic efficiency of total-body PET/CT imaging with fast 2-min acquisition and conventional PET/CT was similar.

Radiopaque drug-eluting embolisation beads as fiducial markers for stereotactic liver radiotherapy

Objective: To determine the feasibility of using radiopaque (RO) beads as direct tumour surrogates for image-guided radiotherapy (IGRT) in patients with liver tumours after transarterial chemoembolisation (TACE). Methods: A novel vandetanib-eluting RO bead was delivered via TACE as part of a first-in-human clinical trial in patients with either hepatocellular carcinoma or liver metastases from colorectal cancer. Following TACE, patients underwent simulated radiotherapy imaging with 4-dimensional computed tomography (4D-CT) and cone-beam CT (CBCT) imaging. RO beads were contoured using automated thresholding, and feasibility of matching between the simulated radiotherapy planning dataset (AVE-IP image from 4D data) and CBCT scans assessed. Additional kV, MV, helical CT and CBCT images of RO beads were obtained using an in-house phantom. Stability of RO bead position was assessed by comparing 4D-CT imaging to CT scans taken 6–20 days following TACE. Results: Eight patients were treated and 4D-CT and CBCT images acquired. RO beads were visible on 4D-CT and CBCT images in all cases and matching successfully performed. Differences in centre of mass of RO beads between CBCT and simulated radiotherapy planning scans (AVE-IP dataset) were: 2.0 mm mediolaterally, 1.7 mm anteroposteriorally, 3.5 mm craniocaudally. RO beads in the phantom were visible on all imaging modalities assessed. RO bead position remained stable up to 29 days post-TACE. Conclusion: RO beads are visible on IGRT imaging modalities, showing minimal artefact. They can be used for on-set matching with CBCT and remain stable over time. Advances in knowledge: The role of RO beads as fiducial markers for stereotactic liver radiotherapy is feasible and warrants further exploration as a combination therapy approach.

Major Hepatectomy En Bloc with Cava Vein Resection for Locally Invasive Caudate Lobe Hepatocarcinoma

Background/Aim: Locally advanced liver tumours with vascular invasion have been considered for a long period of time as unresectable lesions, so the patient was further deferred to oncology services for palliation. However, improvement of the surgical techniques and the results reported so far came to demonstrate that extended hepatic and vascular resections might be safely performed in such cases and might significantly improve the long-term outcomes. Materials and Methods: A 61-year-old patient was diagnosed with a caudate lobe tumour invading the inferior cava vein and the right hepatic pedicle. Results: The patient was successfully submitted to surgery, and an extended right hepatectomy en bloc with cava vein resection was performed; the continuity of the cava vein was re-established by the placement of a synthetic graft. The postoperative outcome was uneventful. Conclusions: Although initially considered as a formal contraindication for resection, vascular invasion of the greater vessels should not preclude surgery if complete resection is achievable.

TP6.2.6 A meta-analysis and systematic review of Laparoscopic versus open hepatectomy for malignant liver tumours in the elderly patients

Aims To evaluate comparative outcomes of laparoscopic versus open hepatectomy for malignant liver tumours in elderly patients. Methods A systematic online search was conducted using the following databases: PubMed, Scopus, Cochrane database, The Virtual Health Library, Clinical trials.gov and Science Direct. Comparative studies comparing laparoscopic (LH) versus open hepatectomy (OH) for both primary and metastatic malignant liver tumours in the elderly were included. Total operative time (minutes), need to perform Pringle’s manoeuvre, blood loss (ml), requirement for blood transfusion intra-operatively/post-operatively, post-operative complications, R0 resection rate, specimen resection margin (mm), re-operation rate, length of hospital stay (LOS), and 90-day mortality were the evaluated outcome parameters. Results Twelve studies reporting a total number of 1762 patients who underwent laparoscopic (n = 831) or open (n = 931) hepatectomy were included. OH group was associated with a significantly higher number of post-operative complications compared to LH (P = 0.00001). Complications such as post-operative liver failure (P = 0.02), ascites formation (P = 0.002), surgical site infection (P = 0.02), blood loss (P = 0.03), blood transfusion rate (P = 0.05) and LOS (P = 0.00001) were significantly higher in the OH group when compared to LH. There was no significant difference between the two groups in terms of total operative time (P = 0.53), bile leak (P = 0.12), R0 resection rate (P = 0.36), re-operation (P = 0.70) and 90-day mortality (P = 0.11). Conclusion Laparoscopic liver resections are safe with at least equal or superior peri-operative outcomes in the elderly population. Importantly, oncological outcomes are also comparable with open surgery. This approach needs to be utilised wherever possible to provide optimal healthcare in an aging population.

EP.TH.43Biliary cooling during radiofrequency ablation of liver tumours close to central biliary tree: A systematic review and pooled analysis

Aims Biliary cooling during radiofrequency ablation (RFA) of liver tumours has been proposed as a protective measure for RFA-related biliary complications in cases whereby the RFA-site is close to central biliary tree. This systematic review aims to assess the effect of biliary cooling on i) the development of biliary complications and ii) tumour recurrence rates at ablation site. Methods A systematic literature search was performed using the PubMed/EMBASE databases using PRISMA methodology (2000-2019). The initial search yielded 75 reports which were potentially suitable for inclusion. Studies reporting at least one outcome of interest were considered to be suitable for inclusion. Conference abstracts, case reports and animal studies were excluded. Data was retrieved on patient demographics, tumour characteristics, method of cooling, biliary complications, local tumour recurrence and duration of follow-up. Results The final number of studies which met the inclusion criteria was 7, involving 100 patients. There were no randomized controlled trials identified after the literature search. The mean age of the patients included was 65 years. Biliary cooling was performed with the use of a nasobiliary tube in 4 out of 7 studies, via a choledochal incision in 2 out of 7 studies and through the cystic duct in a single study. The overall biliary stricture rate was 2% and the overall tumour recurrence rate at RFA treated site was 14.5%. Conclusion Biliary complications appear to be low after biliary cooling during RFA close to central biliary tree. More evidence is required to assess the tumour recurrence rates.

Ras/MAPK signalling intensity defines subclonal fitness in a mouse model of primary and metastatic hepatocellular carcinoma

Quantitative differences in signal transduction are to date an understudied feature of tumour heterogeneity. The MAPK Erk pathway, which is activated in a large proportion of human tumours, is a prototypic example of distinct cell fates being driven by signal intensity. We have used primary hepatocyte precursors transformed with different dosages of an oncogenic form of Ras to model subclonal variations in MAPK signalling. Orthotopic allografts of Ras-transformed cells in immunocompromised mice gave rise to fast-growing aggressive tumours, both at the primary location and in the peritoneal cavity. Fluorescent labelling of cells expressing different oncogene levels, and consequently varying levels of MAPK Erk activation, highlighted the selection processes operating at the two sites of tumour growth. Indeed, significantly higher Ras expression was observed in primary as compared to metastatic tumours, despite the evolutionary trade-off of increased apoptotic death in the liver that correlated with high Ras dosage. Analysis of the immune tumoral microenvironment at the two locations suggests that fast metastatic growth in the immunocompromised setting is abrogated in immunocompetent animals due to efficient antigen presentation by peritoneal dendritic cells. Furthermore, our data indicate that, in contrast to the metastatic outgrowth, strong MAPK signalling is required in the primary liver tumours to resist elimination by NK cells. Overall, this study describes a quantitative aspect of tumour heterogeneity and highlights potential vulnerability of a subtype of hepatocellular carcinoma as a function of MAPK Erk signalling intensity.