Hepatitis B virus DNA methylation and its potential role in chronic hepatitis B.

Hepatitis B virus (HBV) infection led to 66% liver deaths world-wide in year 2015. Thirty-seven per cent of these deaths were the result of chronic hepatitis B (CHB)-associated hepatocellular carcinoma (HCC). Although early diagnosis of HCC improves survival, early detection is rare. Methylation of HBV DNA including covalently closed circular DNA (cccDNA) is more often encountered in HCC cases than those in CHB and cirrhosis. Three typical CpG islands within the HBV genome are the common sites for methylation. The HBV cccDNA methylation affects the viral replication and protein expression in the course of infection and may associate with the disease pathogenesis and HCC development. We review the current findings in HBV DNA methylation that provide insights into its role in HCC diagnosis.

Interplay of autophagy and cancer stem cells in hepatocellular carcinoma.

Liver cancer is the sixth most common cancer and the fourth leading cause of cancer deaths in the world. The most common type of liver cancers is hepatocellular carcinoma (HCC). Autophagy is the cellular digestion of harmful components by sequestering the waste products into autophagosomes followed by lysosomal degradation for the maintenance of cellular homeostasis. The impairment of autophagy is highly associated with the development and progression of HCC although autophagy may be involved in tumour-suppressing cellular events. In regards to its protecting role, autophagy also shelters the cells from anoikis- a programmed cell death in anchorage-dependent cells detached from the surrounding extracellular matrix which facilitates metastasis in HCC. Liver cancer stem cells (LCSCs) have the ability for self-renewal and differentiation and are associated with the development and progression of HCC by regulating stemness, resistance and angiogenesis. Interestingly, autophagy is also known to regulate normal stem cells by promoting cellular survival and differentiation and maintaining cellular homeostasis. In this review, we discuss the basal autophagic mechanisms and double-faceted roles of autophagy as both tumour suppressor and tumour promoter in HCC, as well as its association with and contribution to self-renewal and differentiation of LCSCs.

Expression of LC3A, LC3B and p62/SQSTM1 autophagy proteins in hepatocellular carcinoma (HCC) tissues and the predicted microRNAs involved in the autophagy-related pathway.

BACKGROUND: Autophagy plays multifaceted roles in regulating hepatocellular carcinoma (HCC) and the mechanisms involved are under-explored. Regulatory microRNAs (miRNAs) have been reported to target autophagy proteins but their roles in HCC is not well studied. Using HCC patient tissues, this study aims to investigate the association of autophagy with several clinicopathological parameters as well as identifying the autophagy-related miRNAs and the possible pathways. METHODS AND RESULTS: Autophagy level in the HCC patient-derived cancer and non-cancer tissues was determined by immunohistochemistry (IHC) targeting SQSTM1, LC3A and LC3B proteins. Significance tests of clinicopathological variables were tested using the Fisher's exact or Chi-square tests. Gene and miRNA expression assays were carried out and analyzed using Nanostring platform and software followed by validation of other online bioinformatics tools, namely String and miRabel. Autophagy expression was significantly higher in cancerous tissues compared to adjacent non-cancer tissues. High LC3B expression was associated with advanced tumor histology grade and tumor location. Nanostring gene expression analysis revealed that SQSTM1, PARP1 and ATG9A genes were upregulated in HCC tissues compared to non-cancer tissues while SIRT1 gene was downregulated. These genes are closely related to an autophagy pathway in HCC. Further, using miRabel tool, three downregulated miRNAs (hsa-miR-16b-5p, hsa-miR-34a-5p, and hsa-miR-660-5p) and one upregulated miRNA (hsa-miR-539-5p) were found to closely interact with the abovementioned autophagy-related genes. We then mapped out the possible pathway involving the genes and miRNAs in HCC tissues. CONCLUSIONS: We conclude that autophagy events are more active in HCC tissues compared to the adjacent non-cancer tissues. We also reported the possible role of several miRNAs in regulating autophagy-related genes in the autophagy pathway in HCC. This may contribute to the development of potential therapeutic targets for improving HCC therapy. Future investigations are warranted to validate the target genes reported in this study using a larger sample size and more targeted molecular technique.

Pancreatobiliary and pancreatoduodenal fistulae in intraductal papillary mucinous neoplasm of the pancreas: report of a case.

Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas present more commonly in the elderly. This report describes a case of IPMN in a 36-year-old man who presented with obstructive jaundice and weight loss. The initial investigation by computed tomography scan revealed a cystic lesion in the head of pancreas fistulating into the duodenum and the common bile duct (CBD). Subsequent endoscopic retrograde cholangiopancreatography revealed a low CBD stricture with proximal filling defects. Mucin was observed extruding from the biliary orifice following an endoscopic sphincterotomy. A classic Whipple's pancreatoduodenectomy was performed to excise the lesion. A histological examination of the lesion confirmed the presence of a malignant IPMN of the pancreas complicated by pancreatobiliary and pancreatoduodenal fistulae.

A modified technique of pancreaticogastrostomy with short internal stent: A single surgeon's experience.

BACKGROUND/OBJECTIVE: Postoperative pancreatic fistula (POPF) remains an important cause of morbidity and mortality after pancreaticoduodenectomy. Pancreaticogastrostomy (PG) as a reconstruction method after pancreaticoduodenectomy is a safe and optional surgical technique in decreasing the risk of POPF. In this study, a retrospective analysis was carried out to evaluate a new modification of PG technique that uses a two-layer anastomoses with an internal stent. METHODS: Forty-seven patients underwent this newly modified PG technique between February 2012 and August 2016. Demographics, histopathological findings, type of surgery performed, perioperative parameters, postoperative length of stay, postoperative complications and interventional procedures, follow-up, and mortality data were collected and analyzed. Clavien-Dindo classification was used to grade the complications' severity. RESULTS: Postoperative mortality was 4.25%, unrelated to POPF, and postoperative morbidity was 44.68%. Thirteen patients had severe (>Grade IIIa) complications, according to Clavien-Dindo classification. As classified in accordance to the International Study Group of Pancreatic Fistula, 24 (51.06%) patients developed Grade A POPF, and no occurrence of Grade B/C POPF was noted. All patients recovered uneventfully with successful treatment interventions. CONCLUSION: The reported PG anastomotic technique is a safe and dependable reconstruction procedure with acceptable morbidity and mortality.

18F-fluorodeoxyglucose positron emission tomography in management of pancreatic cystic tumors.

OBJECTIVES: To evaluate the effectiveness of PET in differentiating malignant from benign pancreatic cystic tumors. METHODS: Between 2009 and 2010, all patients with pancreatic cystic tumors who had PET, triple phase contrast computed tomography (CT) and endoscopic ultrasound (EUS) were reviewed. Clinicopathological characteristics and final histology were correlated with preoperative PET, CT and EUS to assess the value of each modality in detecting malignant from benign lesions for clinical decision-making. RESULTS: Twenty of a total of 116 patients with pancreatic cystic tumors had 18F-FDG PET because of diagnostic difficulties after evaluation with conventional modalities. Sensitivity and specificity of PET in differentiating malignant from benign pancreatic cystic tumors were 100% and 93.75%, with an accuracy of 95%. PET had the best sensitivity, specificity and accuracy for detecting malignant cystic tumors compared with CT and EUS. In 5 cases, the PET results altered the treatment options completely to follow-up instead of surgery (n=2), limited resection instead of Whipple's resection (n=1), and surgery instead of follow-up (n=2). CONCLUSIONS: PET is an accurate, non-invasive method to distinguish malignant from benign pancreatic cystic tumors and can be used as an adjunct to facilitate clinical decision making.

Cutaneous metastasis of hepatocellular carcinoma diagnosed by fine needle aspiration cytology and Hep Par 1 immunopositivity.

Cutaneous metastasis of hepatocellular carcinoma (HCC) is very rare, accounting for less than 0.8% of all known cutaneous metastases and occurring in 2.7-3.4% of HCCs. With less than 50 such cases reported worldwide, most of which were diagnosed histologically on excised lesions, it can only be expected that diagnosis made on cytological features alone would be challenging. We report a case of cutaneous metastasis of HCC diagnosed based on cytological features and confirmed by Hep Par 1 immunopositivity of the cell block material. An 81-year-old man, who was known to have unresectable HCC, presented with a 1-month history of painless, left nasal alae mass. The mass measured 1.5 cm in diameter, and was multilobulated with a central necrosis. Fine needle aspiration of the mass was done. Smears were cellular, comprising of malignant cells in loose clusters and aggregates as well as singly dispersed. The malignant cells displayed moderate nuclear pleomorphism, occasional prominent nucleoli, and intranuclear pseudoinclusion. Cell block material demonstrated the trabeculae pattern of the malignant cells and Hep Par 1 immunopositivity. The final diagnosis of a metastatic cutaneous HCC was made. In conclusion, cutaneous HCC metastasis is rare and should be considered in the differential diagnosis in patients with a history of HCC presenting with suspicious skin lesion. In the right clinical setting, a confident diagnosis can be made in such cases by using the fine needle aspiration technique aided with immunopositivity for Hep Par 1 antibody of the aspirated material.

A novel technique of partial splenectomy using radiofrequency ablation.

INTRODUCTION: Partial splenectomy has frequently been advocated to avoid the risk of overwhelming postsplenectomy sepsis. Concerns over adequate haemostasis during partial splenectomy, however, have limited its widespread use. We have previously reported our experience of using radiofrequency (RF) ablation to minimise blood loss during hepatic and splenic resections. METHODS: In this video, we illustrate the technique of partial splenectomy assisted by RF energy to minimise blood loss.

Duodenal duplication cyst (DDC) communicating with the pancreatobiliary duct--a rare cause of recurrent acute pancreatitis in adults.

INTRODUCTION: Duodenal duplication cysts (DDC) are rare congenital anomalies that usually present in infancy and childhood. Acute presentation in adults is even rarer. CASE HISTORY: We report a case of a 34-year-old man who presented with recurrent acute pancreatitis and was found to have a cystic lesion in the second part of his duodenum. Further investigations revealed communication between the cystic lesion and the distal common bile duct. We describe the details of the operative approach taken to resect the DDC. DISCUSSION: We describe the differential diagnoses and the criteria for diagnosing DDC. Management options for DDC are discussed along with our recommendations.