Distinguishing well-differentiated hepatocellular carcinoma from benign liver by the physical features of fine-needle aspirates

Significance of hepatocyte atypia in liver fine needle aspiration

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

Spontaneous hepatic haemorrhage secondary to ruptured hepatocellular adenoma in a young male patient

A 27-year-old man presented with acute right upper quadrant abdominal pain and vomiting. He was clinically in hypovolaemic shock. Investigations revealed normocytic anaemia with a normal bilirubin and moderate liver function test abnormalities. CT abdomen and pelvis demonstrated haemoperitoneum and a large solitary hepatic mass in segments V and VI, suspicious for a ruptured hepatic tumour. Massive transfusion protocol was commenced and angioembolisation of the inferior branch of the right hepatic artery was undertaken. Despite this, his haemorrhagic shock was resistant to resuscitation. Thus, he underwent emergent exploratory laparotomy, which resulted in segments V and VI liver resection and packing. Re-look laparotomy 2 days following initial exploration was performed where haemostasis was confirmed. Histopathology revealed a ruptured well-differentiated hepatocellular adenoma. The patient made a good recovery following a 2-week admission.

Diagnosis of Liver Neoplasms by Computational and Statistical Image Analysis

Background

Distinguishing well-differentiated hepatocellular carcinoma (WD-HCC), hepatocellular adenoma (HA) and non-neoplastic liver tissue (NNLT) solely on morphology is often challenging. The purpose of this study was to evaluate the use of computational image analysis to distinguish WD-HCC, HA and NNLT.

Methods

Seventy-seven cases comprising of WD-HCC (n = 26), HA (n = 23) and NNLT (n = 28) were retrieved and reviewed. A total of 485 hematoxylin and eosin (H&E) photomicrographs (× 400, 0.09 µm²) of WD-HCC (n = 183), HA (n = 173), NNLT (n = 129) and nine whole-slide scans (three of each diagnosis) were obtained, color deconvoluted and digitally transformed. Quantitative data including nuclear density, nuclear sphericity, nuclear perimeter, and nuclear eccentricity from each image were acquired. The data were analyzed by one-way analysis of variance (ANOVA) with Tukey post hoc test, followed by unsupervised and supervised (Chi-square automatic interaction detection (CHAID)) cluster analysis.

Results

Unsupervised cluster analysis identified three well defined clusters of WD-HCC, HA and NNLT. Employing the four most discriminating nuclear features, supervised analysis was performed on a training set of 383 images, and validated on the remaining 102 test images. The analysis identified WD-HCC (sensitivity 100%, specificity 98%), HA (sensitivity 71%, specificity 85%) and NNLT (sensitivity 70%, specificity 86%). An analysis of whole-slide images identified WD-HCC with sensitivity and specificity of 100%.

Conclusions

We have successfully demonstrated that computational image analysis of nuclear features can differentiate WD-HCC from non-malignant liver with high accuracy, and can be used to assist in the histopathological diagnosis of hepatocellular carcinoma.

Touch cytology smear of an inflammatory hepatocellular adenoma displaying an unusual pattern: A case report

The cytological diagnosis of hepatocellular adenoma (HCA) is difficult since it is a very rare tumor and lacks characteristic cytological features. We have just reported a case of inflammatory HCA that displayed an unusual histological pattern (Clin J Gastroenterol 8:426-434, 2015). A touch cytology smear sample was obtained from the surgical specimen, and it also exhibited very unique features. A 56-year-old male underwent partial hepatectomy for an inflammatory HCA (diameter: 1.4 cm) in the right posterior lobe of the liver. The cytological sample displayed a characteristic two-cell pattern. One type of cells contained thick cytoplasm, a high nucleus/cytoplasmic (N/C) ratio, and well-defined cytoplasmic borders. The other type demonstrated small pyknotic nuclei and a lower N/C ratio. The immunohistochemical staining pattern of the histological specimen suggested that the latter cells might have been undergoing apoptosis. We report a case of inflammatory HCA with characteristic features. To diagnose this type of variant, it is important to recognize the unique pattern described in this study. Diagn. Cytopathol. 2016;44:1074-1077. © 2016 Wiley Periodicals, Inc.

Differential biodistribution of oncolytic poxvirus administered systemically in an autochthonous model of hepatocellular carcinoma

BACKGROUND

Preclinical studies have demonstrated that, unlike oncolytic adenoviruses, oncolytic vaccinia viruses can reach implanted tumors upon systemic injection. However, the biodistribution of this oncolytic agent in in situ autochthonous tumor models remains poorly characterized. In the present study, we assessed this biodistribution in a model of mouse hepatocellular carcinoma (HCC) obtained after injection of the carcinogen diethylnitrosamine (DEN).

METHODS

Twelve months after DEN administration, histology, quantitative reverse transcription-polymerase chain reaction, in situ hybridization and viral titration were used to characterize tumors, as well as to assess the viral load of the livers upon either intravenous or intraperitoineal injection.

RESULTS

The results obtained showed that the architecture of the liver was lost, with a noticeable absence of sinusoids, as well as the presence of steatosis and α-fetoprotein-positive HCC tumor nodules. Bioluminescence imaging and measures of the infective virus load demonstrated that intravenous injection of 10(8)  plaque-forming units of the recombinant vaccinia virus led to a predominant transduction of the liver, whereas intraperitoneal injection resulted in a lower level of liver transduction accompanied by an increased infection of the lungs, spleen, kidneys and bowels. Immunohistochemical analysis of liver sections of animals injected intravenously with the virus revealed a preferential localization of vaccinia-specific immunoreactivity in the tumors.

CONCLUSIONS

The findings of the present study emphasize the importance of the route of administration of the vector and highlight the relevance of systemic injection of oncolytic vaccinia virus in the context of hepatocellular carcinoma.

Alcohol induces liver neoplasia in a novel alcohol-preferring rat model

BACKGROUND

Alcohol is a significant risk factor for the development of hepatocellular carcinoma (HCC). To date, no rodent model has demonstrated the formation of hepatic neoplasia in the setting of chronic alcohol consumption alone.

METHODS

We investigated whether rats selectively bred for high alcohol preference (P rats), allowed free access to water, or water and 10% (v/v) alcohol, for 6, 12, or 18 months, develop hepatic neoplasia.

RESULTS

At necropsy, liver tumor incidence and multiplicity were significantly increased in 18-month alcohol-consuming versus water-consuming P rats. These data were confirmed histologically by glutathione-S-transferase pi-class (GSTp) staining. Phosphorylated mitogen-activated protein kinase/extracellular signal-regulated kinase 1/2 (MAPK/ERK) staining was also increased in the sinusoidal lining cells within livers of alcohol-consuming versus water only P rats. In addition, cytochrome p450IIE1 (CYP2E1) mRNA, protein expression/activity, and intrahepatic oxidative stress were significantly increased in alcohol-consuming P rat livers versus water only. In contrast, acetaldehyde dehydrogenase expression decreased in alcohol-consuming versus water only P rats. No significant difference in alcohol dehydrogenase expression was detected.

CONCLUSIONS

These data demonstrate that chronic alcohol consumption is associated with hepatic neoplasia, MAPK/ERK activation, increased CYP2E1 activity, and intrahepatic oxidative stress in P rats. As these rats are well characterized as a model of alcoholism, these findings identify a novel rodent model of alcohol or "alcoholism"-induced liver neoplasia.

Percutaneous radiofrequency ablation of hepatocellular adenoma: initial experience in 10 patients

BACKGROUND AND AIM

The purpose of this study was to assess the therapeutic efficacy and safety of percutaneous radiofrequency (RF) ablation for hepatocellular adenoma.

METHODS

We performed percutaneous RF ablation in 10 patients with pathologically proven hepatocellular adenomas. Eight patients were asymptomatic and two patients had a recurrent tumor after surgical resection. The size of the tumors was 2.25 +/- 0.76 cm (range: 1.5-4.5 cm) in the largest diameter. All ablation procedures were percutaneously performed with an internally cooled RF electrode system under ultrasound (US) guidance. We evaluated the therapeutic efficacy and safety of the procedure by clinical follow-up data with regular follow-up computed tomography (CT) for 2-35 months (mean, 17.5 months).

RESULTS

All patients well tolerated percutaneous RF ablation procedure without any incident. Contrast-enhanced CT (n = 7) or contrast-enhanced US (n = 3) obtained immediately (<24 h) after the procedure revealed complete ablation of the tumor in all cases. There was no case of local tumor progression or new recurrence during the follow-up period. We found neither procedure-related mortality nor major complication requiring specific treatment.

CONCLUSION

Percutaneous RF ablation of hepatocellular adenoma without overt complication can be a new potential alternative to close imaging follow-up or elective surgery.

Identification of a unique gene expression signature that differentiates hepatocellular adenoma from well-differentiated hepatocellular carcinoma

It is often difficult to distinguish hepatocellular adenoma (HCA) from well-differentiated hepatocellular carcinoma (WDHCC) when limited tissue from a needle biopsy is evaluated. The aim of this study was to identify gene expression patterns that can distinguish HCA from WDHCC, with the ultimate goal of discovering novel diagnostic markers. Gene expression profile analysis was performed using Affymetrix U133Plus2 GeneChip microarrays on RNA isolated from frozen tissue of 6 HCA and 8 WDHCC specimens. Statistical analysis of microarray data identified 63 genes whose expression levels were significantly different between HCA and WDHCC. These included 57 genes overexpressed by HCA and 6 overexpressed by WDHCC. Eight genes were chosen for further analysis by quantitative RT-PCR on RNA derived from archived, paraffin-embedded tissue blocks of an independent validation set comprising 9 HCAs and 9 HCCs. Seven of the 8 genes demonstrated average expression differences between HCA and HCC that were concordant with the microarray findings, and their expression pattern correctly classified the 18 tumors into HCA and HCC using unsupervised clustering analysis. Furthermore, immunohistochemical staining performed on a third, independent set of 27 HCAs and 33 HCCs confirmed the expression differences at protein levels for 5 of the genes. Taken together, our data demonstrate significant molecular differences between HCA and WDHCC, despite their morphologic similarity. More importantly, we have identified a unique set of genes whose expression pattern can discriminate between these two types of hepatocellular neoplasms, suggesting the possibility of future development of ancillary molecular and immunohistochemical diagnostic methods.

Fibrolamellar hepatocellular carcinoma: A case report with cytological features in a sixteen-year-old girl

We report a case of a 16-yr-old girl with a liver tumor revealed by thrombophlebitis of the left leg. On physical examination the patient was found to have painless hepatomegaly. Ultrasound and CAT scan showed a large tumor of the left portion of the liver, measuring 14 cm in diameter. Cytological preparations were touch imprints of the biopsy fragments obtained under ultrasound guidance. Cytological examination using May-Grünwald Giemsa stain revealed highly cellular smears containing large tumor cells with a round nucleus, prominent nucleoli, and abundant granular basophilic cytoplasm. Cytological features were those of fibrolamellar hepatocellular carcinoma, confirmed by histological examination of the biopsy sample as well as the surgical specimen obtained after wide excision of the lesion following ineffective neoadjuvant chemotherapy.

Diagnosis of focal nodular hyperplasia of the liver by needle biopsy

Focal nodular hyperplasia (FNH) of the liver can be a difficult diagnosis to establish in limited diagnostic samples such as a needle-core tissue biopsy, especially for pathologists with limited experience with the lesion. To characterize the features that can be used to make the diagnosis, we reviewed and analyzed the clinicopathologic features of 100 consecutive cases submitted for consultation in which we were confident of the diagnosis of FNH in needle biopsy material. A diagnosis of FNH was correctly made by the contributing pathologist in 24 of the 100 referred cases. Most of the patients (81%) were women of childbearing age with a mean age of 36.75 +/- 9.82 years. Most of the patients (70%) were asymptomatic at diagnosis. The most consistent diagnostic histological feature of FNH in needle biopsy was the presence of ductular reaction with varied intensity at the junction of the fibrous septa with the hepatocellular component, which was present in all 100 cases. Thick abnormal arteries were seen in all but 2 cases (n = 98). Features of chronic cholestasis with cholate stasis and accumulation of copper (demonstrable by the rhodanine stain) and copper-binding protein (demonstrable with the Victoria blue stain) were nearly as common (n = 94). A confident diagnosis of FNH can be made with a needle biopsy, especially if the biopsy is known to come from a mass, and the lesion contains characteristic fibrosis with ductules at the interface between hepatocytes and the fibrous region, prominent arteries, and benign hepatocytes with features of chronic cholestasis.

Hepatobiliary pathology

PURPOSE OF REVIEW

This review highlights recent publications on hepatobiliary pathology concerning several unusual types of hepatitis, fatty liver disease, disorders of the biliary tree and other topics that have a substantial impact on liver biopsy interpretation.

RECENT FINDINGS

In the outbreak of severe acute respiratory syndrome (SARS), many patients had abnormalities in liver function tests. Liver biopsy findings in three cases were reported that showed a generic picture of hepatitis, with exceptionally increased mitotic activity. The role of portal myofibroblasts in cirrhosis was examined in several studies. A newly described lesion, isolated ductular hyperplasia (IDH) was found in patients with prolonged abnormalities of liver function tests of uncertain origin. Hyperplastic, well-differentiated bile ductules were seen on liver biopsy in the absence of any identifiable biliary disease. Hereditary hemochromatosis is now a complex entity with various clinicopathological forms based on mutations in the HFE gene and other iron-homeostatic genes such as transferrin receptor 2 and ferroportin 1. In some of these heritable forms of primary iron overload, stainable iron is present in both hepatocytes and Kupffer cells. After liver transplantation, differentiating recurrent HCV infection from acute rejection on liver biopsy is problematic, with exceptionally low inter- and intra-observer reliability shown in one study.

SUMMARY

The hepatitis associated with the SARS coronavirus, Isolated Ductular Hyperplasia in patients with liver function test abnormalities and other topics with pathologic relevance are reviewed.

Successful Treatment of Hepatocellular Adenoma with Percutaneous Radiofrequency Ablation

OBJECTIVE

The purpose of our study was to report the safe and successful treatment of hepatocellular adenoma with percutaneous radiofrequency ablation.

CONCLUSION

Our limited experience indicates that percutaneous radiofrequency ablation is both safe and effective in the treatment of the small hepatocellular adenoma in carefully selected patients.