Risk Factors for Hospitalization Duration Longer Than 24 Hours Following Percutaneous Radiofrequency Ablation of Liver Tumours.

PURPOSE: Prior studies have described complications of radiofrequency ablation (RFA) of liver tumours. The aim of this study was to identify risk factors for hospitalization duration longer than 24 hours following RFA of liver tumours. METHODS: This retrospective, single-centre study included patients with liver tumours undergoing RFA between October 2017 and July 2020. Medical records were reviewed to collect patient, tumours, and procedure characteristics for each RFA session. The association between potential risk factors and duration of hospitalization (less than or more than 24 hours) was analyzed using univariate and multivariate logistic regressions. RESULTS: Our study included 291 patients (mean age: 65.2 ± 11.2 [standard deviation]; 201 men) undergoing 324 RFA sessions. Sixty-eight sessions (21.0%) resulted in hospitalization of more than 24 hours. Multivariate analysis identified each additional needle insertion per session (OR 1.4; 95% CI [1.1-1.9]; P = .02), RFA performed in segment V (OR 2.8; 95% CI [1.4-5.7]; P = .004), and use of artificial pneumothorax (OR 14.5; 95% CI [1.4-146.0]; P = .02) as potential risk factors. A history of hepatic encephalopathy (OR 2.6; 95% CI [1.1-6.0]; P = .03) was only significant in univariate analysis. Post-hoc, subgroup analysis of patients with hepatocellular carcinoma (69.8%) did not identify other risk factors. CONCLUSION: Risk factors for a hospitalization duration longer than 24 hours include a higher number of needle insertions per session, radiofrequency ablation in segment V, and use of an artificial pneumothorax.

Comparative Study of Ablation Zone of EMPRINT HP Microwave Device with Contemporary 2.4 GHz Microwave Devices in an Ex Vivo Porcine Liver Model.

(1) Background: Percutaneous microwave ablation (MWA) is an accepted treatment of non-operative liver cancer. This study compares the ablation zones of four commercially available 2.45 GHz MWA systems (Emprint, Eco, Neuwave, and Solero) in an ex vivo porcine liver model. (2) Methods: Ex vivo porcine livers (n = 85) were obtained. Two ablation time setting protocols were evaluated, the manufacturer's recommended maximum time and a 3 min time, performed at the manufacturer-recommended maximum power setting. A total of 236 ablation samples were created with 32 (13.6%) samples rejected. A total of 204 samples were included in the statistical analysis. (3) Results: For single-probe protocols, Emprint achieved ablation zones with the largest SAD. Significant differences were found in all comparisons for the 3 min time setting and for all comparisons at the 10 min time setting except versus Neuwave LK15 and Eco. Emprint produced ablation zones that were also significantly more spherical (highest SI) than the single-probe ablations from all other manufacturers. No statistical differences were found for ablation shape or SAD between the single-probe protocols for Emprint and the three-probe protocols for Neuwave. (4) Conclusions: The new Emprint HP system achieved large and spherical ablation zones relative to other 2.45 GHz MWA systems.

Epidemiological Study of Malignant Paediatric Liver Tumours in Denmark 1985-2020.

BACKGROUND: Malignant liver tumours in children are rare and national outcomes for this tumour entity are rarely published. This study mapped paediatric liver tumours in Denmark over 35 years and reported on the incidence, outcomes and long-term adverse events. METHODS: We identified all liver tumours from the Danish Childhood Cancer Registry and reviewed the case records for patient and tumour characteristics, treatment and clinical outcome. RESULTS: We included 79 patients in the analyses. Overall crude incidence was ~2.29 per 1 million children (<15 yr) per year, with 61 hepatoblastomas (HB), 9 hepatocellular carcinomas and 9 other hepatic tumours. Overall 5-year survival was 84%, 78% and 44%, respectively. Nine patients had underlying liver disease or predisposition syndrome. Seventeen children underwent liver transplantation, with two late complications, biliary stenosis and liver fibrosis. For HB, age ≥ 8 years and diagnosis prior to 2000 were significant predictors of a poorer outcome. Adverse events included reduced renal function in 10%, reduced cardiac function in 6% and impaired hearing function in 60% (19% needed hearing aids). Behavioural conditions requiring additional support in school were registered in 10 children. CONCLUSIONS: In Denmark, incidences of malignant liver tumours during the last four decades have been increasing, as reported in the literature. HB survival has improved since the year 2000 and is comparable with international results. Reduced hearing is the major treatment-related side effect and affects approximately 60% of patients.

Giant cavernous hemangioma of the liver with satellite nodules: Aspects on tumour/tissue interface: A case report.

BACKGROUND: Giant hepatic cavernous hemangioma with multiple satellite nodules is a rare subtype of hepatic cavernous hemangioma, the most common vascular liver tumor. We report on a tumor with unusual histologic features: (1) Finger-like infiltration pattern; (2) lack of encapsulation; (3) blurred tumor/liver interface; and (4) massive satellitosis-referring to the article "Hepatic cavernous hemangioma: underrecognized associated histologic features". CASE SUMMARY: A 60-year-old man presented with increasing uncharacteristic abdominal discomfort and mildly elevated blood parameters of acute inflammation. Imaging revealed an unclear, giant liver tumor of the left liver lobe. A massive vascular tumor with extensive satellitosis broadly infiltrating the adjacent liver parenchyma was resected via hemihepatectomy of segments II/III. Histopathological diagnosis was giant hepatic cavernous hemangioma with multiple satellite nodules, featuring unusual characteristics hardly portrayed in the literature. Retrospectively, this particular morphology can explain the difficult pre- and perioperative diagnosis of a vascular liver tumor that is usually readily identifiable by modern imaging methods. CONCLUSION: This case emphasizes the exact histological workup of tumor and tumor-induced parenchyma changes in radiologically unclassifiable liver tumors.

Development of a set of patient reported outcome measures for patients with benign liver tumours and cysts: patient focus groups and systematic review.

BACKGROUND: Patient reported outcome measures (PROMs) may be useful for patients with benign liver tumours and cysts (BLTC) to evaluate the impact of treatment and/or guide shared decision making. Yet, a set of PROMs relevant to patients with BLTC is currently unavailable. In this study, we selected a PROMs set for patients with BLTC. METHODS: Potentially relevant patient reported outcomes (PROs) were selected by psychologist-researchers based on keywords used or suggested by participants of two virtual focus groups meetings consisting of thirteen female BLTC patients with a median age of 50 years. Subsequently, patients were asked to report their most relevant PROs. PROMs identified by systematic literature review and computerized adaptive tests (CATs) in the Patient-Reported Outcomes Measurement Information System (PROMIS) were considered in selecting the final PROMs set to assess relevant outcomes. RESULTS: The most important PROs were: insecurity/anxiety (11/12 patients), pain (9/12 patients), fatigue (8/12 patients), and limitations in daily life (5/12 patients). The literature review included 23 studies, which used various generic and disease-specific PROMs, often not measuring (all) relevant PROs. The final selected PROMs set included numerical rating scales for pain, two questions on overall health and quality of life and four PROMIS CATs. CONCLUSIONS: A PROMs set generically and efficiently measuring outcomes relevant for patients with BLTC was developed and may be used in future research and clinical practice.

The frequency and risk factors of major complications after thermal ablation of liver tumours in 2,084 ablation sessions.

Background: To assess the frequency of major complications after thermal ablation of liver tumours and to determine risk factors for adverse events. Methods: A retrospective study was conducted between January 2015 and January 2021. A total of 2,084 thermal ablation sessions in 1,592 patients with primary and metastatic liver tumours were evaluated. The frequency of major complications was evaluated according to the Society of Interventional Radiology Standards, and putative predictors of adverse events were analysed using simple and multivariate logistic regression. Results: Thermal ablation-related mortality was 0.1% (2/2,084), with an overall major complication rate of 5.6% (117/2,084). The most frequent major complication was symptomatic pleural effusion (2.9%, 60/2,084). Multivariate logistic regression analysis revealed that a total maximum diameter of lesions >3 cm, microwave ablation (MWA) and MWA combined with radiofrequency ablation, intrahepatic cholangiocarcinoma and postoperative systemic inflammatory response syndrome were independent prognostic factors for major complications. Conclusions: Thermal ablation of liver tumours is a safe procedure with an acceptable incidence of major complications. The risk factors identified in this study will help to stratify high-risk patients.

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

PURPOSE: To comparatively evaluate the diagnostic performances of total-body 18F-fluorodeoxyglucose positron-emission tomography/computed tomography (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 cutoff: 4.34, TLR cutoff: 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.

Risk factors for bleeding hepatocellular adenoma in a United States cohort.

BACKGROUND & AIMS: Known risk factors for hepatocellular adenoma (HCA) bleeding are size >5 cm, growth rate, visible vascularity, exophytic lesions, ß-catenin and Sonic Hedgehog activated HCAs. Most studies are based on European cohorts. The objective of this study is to identify additional risk factors for HCA bleeding in a US cohort. METHODS: Retrospective chart review was performed on patients diagnosed with HCA on magnetic resonance imaging (n = 184) at an academic tertiary institution. Clinical, pathological, and imaging data were collected. Primary outcomes measured were HCA bleeding and malignancy. Statistical analysis was performed with SAS 9.4 using Chi-Square, Fisher's exact test, sample t test, non-parametric Wilcoxon test, and logistic regression. RESULTS: After excluding patients whose pathology showed focal nodular hyperplasia and non-adenoma lesions, follow-up data were available for 167 patients. 16% experienced microscopic or macroscopic bleeding and 1.2% had malignancy. HCA size predicted bleeding (P < .0001) and no patients with lesion size <1.8 cm bled. In unadjusted analysis, hepatic adenomatosis (≥10 lesions) trended towards 2.8-fold increased risk of bleeding. Of patients with a single lesion that bled, 77% bled from a lesion >5 cm. In patients with multiple HCAs that bled, 50% bled from lesions <5 cm. In patients with multiple adenomas, size (P = .001) independently predicted bleeding and hepatic steatosis trended towards increased risk of bleeding (P = .05). CONCLUSIONS: In a large US cohort, size predicted increased risk of HCA bleeding while hepatic adenomatosis trended towards increased risk of bleeding. In patients with multiple HCAs, size predicted bleeding and hepatic steatosis trended toward increased risk of bleeding.

A Literature Review to Assess Blood Loss in Minimally Invasive Liver Surgery Versus in Open Liver Resection.

Aim and objectives The aim of the study was to assess the amount of blood loss in minimally invasive hepatectomy and open liver resection for both benign and neoplastic conditions. Introduction Minimally invasive surgery has progressively developed to a stage where once-novel and highly specialized surgical techniques are now common practice. Colorectal surgery is the key example that has shown minimally invasive surgery as highly beneficial. Successes in the colorectal laparoscopic approach have now been integrated into the speciality of hepatopancreaticobiiary (HPB) surgery. In this review, we will compare the amount of blood loss in minimally invasive liver resection with the more traditional approach of open liver resection. Methods A literature review was conducted which included the length of patient mobilization as a postoperative complication following laparoscopic and open liver resections. Medline, PubMed, and Cochrane were accessed to review previously published studies. Twelve studies were selected, and all of them were in English, ranged from the year 2000 to 2020. Results Eleven out of the 12 included studies indicated that minimally invasive liver resection is associated with reduced blood loss. Conclusion In comparing both minimally invasive liver resection and classic open surgery, minimally invasive liver resection was shown to have reduced blood loss; this was seen in both malignant and benign tumours. Therefore, laparoscopic liver resection could be favoured over the classical open approach to avoid excessive blood loss intra-operatively.

Laparoscopic versus open hepatectomy for malignant liver tumours in the elderly: systematic review and meta-analysis.

To evaluate comparative outcomes of laparoscopic versus open hepatectomy for malignant liver tumours in elderly patients. 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), the 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. 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 overall 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). Laparoscopic liver resections are safe with at least equal or superior peri-operative outcomes in the elderly population, although available data regards mainly the results of minor resections. Laparoscopic major resections in the elderly population should be carefully evaluated and preferably performed in expert centres.

Sustained-hepatic arterial infusion of oxaliplatin: pharmacokinetic advantages over hepatic arterial infusion using a preclinical animal tumour model.

Hepatic arterial infusion (HAI) of oxaliplatin allows greater liver tumour drug exposure compared to systemic infusion. However, the therapeutic index of HAI oxaliplatin remains poor. Using Pickering emulsion technology, we developed a platform able to provide sustained releases of oxaliplatin. The goal of this study was to evaluate the pharmacokinetic advantages of sustained-HAI oxaliplatin over HAI using a preclinical animal tumour model. Injections of 0.6 mg oxaliplatin in 20 min were selectively done in left hepatic arteries of 20 rabbits bearing a VX2 liver tumour in the middle left-lobe, using HAI (n = 10) or sustained-HAI (n = 10). In each group, half of the rabbits were sacrificed at 24 h and half at 72 h. Mass spectrometry was used to quantify drug pharmacokinetics in blood and oxaliplatin concentrations in tumour tissues, right- and middle left-liver lobes, spleen and lung. Compared to HAI, sustained-HAI of oxaliplatin resulted in lower plasmatic peak (Cmax: 275 ± 41 vs. 416 ± 133 ng/mL, p = 0.02) and higher concentration in the tumour at 24 h (2118 ± 2107 vs. 210 ± 93 ng/g, p = 0.008). After HAI, oxaliplatin concentration in tumours was significantly higher than in lung at 24 h (p = 0.03) but no other difference was found between oxaliplatin concentrations in tumours and in liver lobes, spleen or lung, neither at 24 h nor at 72 h. On the opposite, sustained-HAI resulted in higher concentrations of oxaliplatin in tumour compared to oxaliplatin concentrations in the middle left lobe (163 ± 86 ng/g at 24 h, p = 0.01, and 90 ± 15 ng/g at 72 h, p = 0.04), right lobe (174 ± 112 ng/g at 24 h, p = 0.01, and 112 ± 35 ng/g, p = 0.04 at 72 h), spleen (142 ± 21 ng/g at 24 h, p = 0.01, and 98 ± 12 ng/g at 72 h, p = 0.04), and lung (85 ± 11 ng/g at 24 h, p = 0.01, and 52 ± 4 ng/g at 72 h, p = 0.03). Sustained-HAI improves the therapeutic index of HAI oxaliplatin and offers a great potential for patients suffering from unresectable colorectal liver metastases or hepatocellular carcinoma.

International recommendations for personalised selective internal radiation therapy of primary and metastatic liver diseases with yttrium-90 resin microspheres.

PURPOSE: A multidisciplinary expert panel convened to formulate state-of-the-art recommendations for optimisation of selective internal radiation therapy (SIRT) with yttrium-90 (90Y)-resin microspheres. METHODS: A steering committee of 23 international experts representing all participating specialties formulated recommendations for SIRT with 90Y-resin microspheres activity prescription and post-treatment dosimetry, based on literature searches and the responses to a 61-question survey that was completed by 43 leading experts (including the steering committee members). The survey was validated by the steering committee and completed anonymously. In a face-to-face meeting, the results of the survey were presented and discussed. Recommendations were derived and level of agreement defined (strong agreement ≥ 80%, moderate agreement 50%-79%, no agreement ≤ 49%). RESULTS: Forty-seven recommendations were established, including guidance such as a multidisciplinary team should define treatment strategy and therapeutic intent (strong agreement); 3D imaging with CT and an angiography with cone-beam-CT, if available, and 99mTc-MAA SPECT/CT are recommended for extrahepatic/intrahepatic deposition assessment, treatment field definition and calculation of the 90Y-resin microspheres activity needed (moderate/strong agreement). A personalised approach, using dosimetry (partition model and/or voxel-based) is recommended for activity prescription, when either whole liver or selective, non-ablative or ablative SIRT is planned (strong agreement). A mean absorbed dose to non-tumoural liver of 40 Gy or less is considered safe (strong agreement). A minimum mean target-absorbed dose to tumour of 100-120 Gy is recommended for hepatocellular carcinoma, liver metastatic colorectal cancer and cholangiocarcinoma (moderate/strong agreement). Post-SIRT imaging for treatment verification with 90Y-PET/CT is recommended (strong agreement). Post-SIRT dosimetry is also recommended (strong agreement). CONCLUSION: Practitioners are encouraged to work towards adoption of these recommendations.

Irreversible electroporation in patients with liver tumours: treated-area patterns with contrast-enhanced ultrasound.

BACKGROUND: Familiarity with post-IRE imaging interpretation is of considerable importance in determining ablation success and detecting recurrence. CEUS can be used to assess the tumour response and characteristics of the ablation zone. It is of clinical interest to describe the ultrasonographic findings of liver tumours after irreversible electroporation (IRE) percutaneous ablation. METHODS: A prospective study of 24 cases of malignant liver tumours (22 cases of primary liver tumours and 2 cases of liver metastases) treated by IRE ablation was conducted. Two inspectors evaluated the ablation zone in a consensus reading performed immediately, 1 day, and 1 month after IRE ablation. The gold standard method, magnetic resonance imaging (MRI), was used to evaluate the effectiveness of the treatment at 1 month. RESULTS: Immediately after IRE ablation and up to 1 month later, the ablation zones gradually changed from hypo-echogenicity to hyper-echogenicity on conventional ultrasound and showed non-enhancement on contrast-enhanced ultrasound (CEUS). One month after IRE ablation, CEUS and MRI results were highly consistent (κ = 0.78, p < 0.05). CONCLUSIONS: We conclude that CEUS may be an effective tool for assessing post-IRE ablation changes after 1 month. CEUS enables the depiction of tumour vascularity in real time and serves as an easy, repeatable method.

Liver transplantation for secondary liver tumours: The difficult balance between survival and recurrence.

Assessing the balance between survival and recurrence after transplantation for secondary liver tumours should be based on the type of cancer in question. For neuroendocrine liver metastases, high recurrence rates are clearly related to reduced long-term survival. For colorectal liver metastases, experience to date indicates that pulmonary recurrence alone has a modest impact on survival outcomes. Further studies focusing on this group of patients will be important for the development of this field of transplant oncology. Liver transplantation for secondary liver tumours should be implemented in accordance with stringent transplant criteria and preferably in the context of prospective trials. Expansion of the donor pool by utilising extended criteria donors and partial liver transplantation could be considered for this indication.

Rapid automated diagnosis of primary hepatic tumour by mass spectrometry and artificial intelligence.

BACKGROUND AND AIMS: Complete surgical resection with negative margin is one of the pillars in treatment of liver tumours. However, current techniques for intra-operative assessment of tumour resection margins are time-consuming and empirical. Mass spectrometry (MS) combined with artificial intelligence (AI) is useful for classifying tissues and provides valuable prognostic information. The aim of this study was to develop a MS-based system for rapid and objective liver cancer identification and classification. METHODS: A large dataset derived from 222 patients with hepatocellular carcinoma (HCC, 117 tumours and 105 non-tumours) and 96 patients with mass-forming cholangiocarcinoma (MFCCC, 50 tumours and 46 non-tumours) were analysed by Probe Electrospray Ionization (PESI) MS. AI by means of support vector machine (SVM) and random forest (RF) algorithms was employed. For each classifier, sensitivity, specificity and accuracy were calculated. RESULTS: The overall diagnostic accuracy exceeded 94% in both the AI algorithms. For identification of HCC vs non-tumour tissue, RF was the best, with 98.2% accuracy, 97.4% sensitivity and 99% specificity. For MFCCC vs non-tumour tissue, both algorithms gave 99.0% accuracy, 98% sensitivity and 100% specificity. CONCLUSIONS: The herein reported MS-based system, combined with AI, permits liver cancer identification with high accuracy. Its bench-top size, minimal sample preparation and short working time are the main advantages. From diagnostics to therapeutics, it has the potential to influence the decision-making process in real-time with the ultimate aim of improving cancer patient cure.

Primary hepatic neuroendocrine tumours of liver- a rarity: Single centre analysis of 13 patients.

BACKGROUNDS/AIMS: Primary hepatic neuroendocrine tumours (PHNETs) are a rarity and this rarity imparts management complexities. METHODS: A retrospective analysis of prospectively maintained liver database from 2009 to 2018 was performed and patients with PHNETs were identified and studied for clinical, imaging and pathological features, surgical outcomes, disease free and overall survival. RESULTS: Thirteen patients of PHNET were identified following rigorous investigational protocols, which constituted 0.6% of all liver tumours (2095) in our series. The median age of patients was 50 years (14-65), with male to female ratio of 9:4. Eight patients (62%) underwent hepatic resections as primary treatment, while 5 (38%) patients received peptide receptor radiotherapy, trans-arterial chemotherapy, trans-arterial radiotherapy or a combination of these. In the surgical group at a median follow up of 36 months (range 5-114 months), 4 (50%) patients were alive without disease and disease free survival was 20 months. Median OS in surgical group was 47 months (40-53, 95% confidence interval) that was better but not statistically significant from that of non-surgical treatment group (36 months). CONCLUSIONS: PHNETs are rare tumours that require multidisciplinary treatment approach. Liver directed surgery centred management leads to better clinical outcomes in these selected patients.

Analysis of ß-catenin gene mutations and gene expression in liver tumours of C57BL/10J mice produced by chronic administration of sodium phenobarbital.

In this study liver tumours produced in male and female mice of the low spontaneous liver tumour incidence C57BL/10J strain treated for 99 weeks with 1000 ppm in the diet with the model constitutive androstane receptor (CAR) activator sodium phenobarbital (NaPB) were analysed for ß-catenin mutations by Western immunoblotting and DNA/RNA analysis. Some gene array analysis was also performed to identify genes involved in CAR activation and in ß-catenin and Hras gene mutations. Analysis of 8 male and 2 female NaPB-induced liver tumour samples (comprising 2 adenomas, 6 carcinomas and 2 samples containing separate adenomas and carcinomas) revealed truncated ß-catenin forms in just 4 male liver tumour samples, with the presence of the truncated ß-catenin forms being confirmed by ß-catenin exon 1-3 mutation analysis. Microarray gene expression analysis was performed with three of the NaPB-induced male mouse liver tumour samples where ß-catenin mutations had not been identified by Western immunoblotting and DNA/RNA analysis and with three liver samples from both NaPB-induced non-tumour tissue and control animals. Treatment with NaPB resulted in induction of Cyp2b subfamily gene expression in both NaPB-induced mouse liver tumours and in NaPB-treated non-tumour tissue. In addition, the gene expression analysis demonstrated that the ß-catenin and Hras pathways were not modified in NaPB-induced mouse liver tumours not exhibiting truncated ß-catenin forms. Overall, while chronic administration of the model CAR activator NaPB results in both hepatocellular adenoma and carcinoma in the low spontaneous liver tumour incidence C57BL/10J mouse strain, only 40 % of the liver tumours evaluated in this study had ß-catenin mutations. These results are in agreement with previous studies with the CAR activator oxazepam and demonstrate that mouse liver tumours induced by nongenotoxic CAR activators in the absence of initiation with a genotoxic agent are due to a number of mechanisms, including those largely independent of either the Wnt/ß-catenin signalling pathway or Hras oncogene mutations.

Single-centre retrospective review of risk factors for local tumour progression and complications in radiofrequency ablation of 555 hepatic lesions.

INTRODUCTION: This study aimed to assess safety, local tumour progression (LTP) and risk factors for LTP after radiofrequency ablation (RFA) of liver tumours in a single centre. METHODS: All consecutive patients treated with RFA for liver tumours between January 2009 and October 2012 were included. Previously treated lesions that progressed were excluded. Using electronic medical records, the following data was captured: patient demographics, pre-procedural laboratory results, Child-Pugh status, tumour characteristics, development of tumoral seeding, RFA complications and LTP. Possible risk factors for LTP were identified using Cox regression. RESULTS: In total, 555 liver tumours were treated in 337 patients. 483 (87.0%) hepatocellular carcinomas, 52 (9.4%) colorectal metastases and 20 (3.6%) other tumour types were treated. Mean tumour size was 2.1 ± 1.1 (range 0.4-6.8) cm. Mean follow-up duration was 387 days. 416 (75.0%) lesions had no LTP at the last imaging. 70 (12.6%) patients had minor complications requiring observation, while 7 (1.3%) patients had significant complications requiring prolonged hospitalisation or further interventions. Only one case of tumour seeding was detected. Using multivariate Cox regression, the following factors were statistically significant in predicting LTP: hilar location (relative ratio [RR] 3.988), colorectal metastases (RR 2.075), size (RR 1.290) and younger age (RR 0.982). CONCLUSION: RFA of liver tumours is safe and effective, with a low significant complication rate of 1.3%. Hilar lesions are most prone to LTP, followed by lesions that were larger in size and colorectal metastases. 75.0% of patients showed no LTP at the last follow-up.

Focal nodular hyperplasia of the liver in children: A report of 2 cases.

Focal nodular hyperplasia (FNH) is a benign non-neoplastic lesion of the liver usually found in adults. It is uncommon in children, comprising 2-10% of all pediatric liver tumours. In children, it can occur at all ages, with increased frequency between 6-10 years. We present two cases of FNH in childhood- the first being that of a 5-month-old infant, and the second in a 6-year-old boy. The possibility of congenital FNH had been excluded in the first case. The second case posed diagnostic difficulty initially and was wrongly treated for hepatoblastoma by neoadjuvant chemotherapy, but later correctly diagnosed to be FNH. Both the children are doing well on follow-up. Paediatric FNH though rare, should be kept in mind while dealing with a hepatic mass. Radiological features can be variable and needle sampling may not be sufficient to reach to a diagnosis. Histological examination with glutamine synthetase immunostaining should be performed in doubtful cases to differentiate FNH from other paediatric liver masses, as management differs.

Hepatic pseudolymphoma: a surprising finding in a case with suspected generalisation of lung cancer.

INTRODUCTION: Pseudolymphoma is a rare focal lesion which occurs in different locations. Only about 50 cases of liver pseudolymphoma have been reported so far. The diagnostic process is challenging. The lesion can resemble different malignancies using various imaging methods. No typical laboratory markers are available. The right diagnosis is usually made on the basis of histological examination. CASE REPORT: A 67 years old female patient with lung fibrosis was undergoing assessments for a malignant-appearing focal lesion of the left lung and a focal liver lesion of unknown etiology. Upper lobectomy of the left lung proved lung carcinoma. The liver lesion was suspected for being metastatic, therefore a liver resection followed. The biopsy revealed hepatic pseudolymphoma. It took 150 days from the first positive CT scan until the liver resection. Currently, the patient shows no signs of recurrence. CONCLUSION: Hepatic pseudolymphoma is a rare disease and we have only little experience with it so far. The diagnostic process is challenging, which is clear from the presented case. Only histological and immunohistochemical examinations ruled out a malignancy. A long-term observation of the patient is indicated.