Postpancreatoduodenectomy Hemorrhage Treated by Combined Transcatheter Arterial Embolization and Superior Mesenteric Artery to Iliac Artery Bypass: Report of a Case

Postpancreatectomy hemorrhage is a potentially life-threatening complication. We report herein our experience with a 65-year-old man with locally advanced pancreatic adenocarcinoma who underwent pancreatoduodenectomy with lymphadenectomy following neoadjuvant chemoradiotherapy. On postoperative day 45, he developed massive hematemesis. Angiography revealed active bleeding from the common hepatic artery, and transcatheter coil embolization of that vessel was successfully performed. On postoperative day 64, he again developed massive hematemesis. Angiography revealed active bleeding from the proximal superior mesenteric artery. Immediately after coil embolization of that vessel, bypass grafting between the superior mesenteric artery and the right common iliac artery was performed, using a greater saphenous vein graft. The combination of embolization and bypass grafting is an option for treatment of bleeding from the superior mesenteric artery in an emergent situation.Key words: Superior mesenteric artery, Bleeding, Bypass, Pancreatoduodenectomy, Postpancreatectomy hemorrhagePostpancreatectomy hemorrhage (PPH) is a rare but life-threatening complication, often associated with the presence of a pancreatic fistula or intraabdominal abscess.¹ The mortality associated with arterial bleeding after pancreatoduodenectomy is reportedly between 14.3% and 30.7%.^2–6 With recent advances in interventional radiology techniques, transcatheter arterial embolization (TAE) has become an alternative to surgical treatment.^3,5,7,8 However, it may be difficult to treat these patients with interventional radiology techniques alone, given their often unstable condition. In addition, the inappropriate use of TAE for arterial bleeding, especially after pancreatoduodenectomy, can lead to end-organ infarction and subsequent infection. We report herein our experience with a patient who had bleeding from the superior mesenteric artery (SMA) after pancreatoduodenectomy. This patient was successfully treated using SMA coil embolization followed by creation of an SMA-iliac artery bypass using a greater saphenous vein graft.     

Cross-Protection of Influenza A Virus Infection by a DNA Aptamer Targeting the PA Endonuclease Domain

Amino acid residues in the N-terminal of the PA subunit (PA_N) of the influenza A virus polymerase play critical roles in endonuclease activity, protein stability, and viral RNA (vRNA) promoter binding. In addition, PA_N is highly conserved among different subtypes of influenza virus, which suggests PA_N to be a desired target in the development of anti-influenza agents. We selected DNA aptamers targeting the intact PA protein or the PA_N domain of an H5N1 virus strain using systematic evolution of ligands by exponential enrichment (SELEX). The binding affinities of selected aptamers were measured, followed by an evaluation of in vitro endonuclease inhibitory activity. Next, the antiviral effects of enriched aptamers against influenza A virus infections were examined. A total of three aptamers targeting PA and six aptamers targeting PA_N were selected. Our data demonstrated that all three PA-selected aptamers neither inhibited endonuclease activity nor exhibited antiviral efficacy, whereas four of the six PA_N-selected aptamers inhibited both endonuclease activity and H5N1 virus infection. Among the four effective aptamers, one exhibited cross-protection against infections of H1N1, H5N1, H7N7, and H7N9 influenza viruses, with a 50% inhibitory concentration (IC₅₀) of around 10 nM. Notably, this aptamer was identified at the 5th round but disappeared after the 10th round of selection, suggesting that the identification and evaluation of aptamers at early rounds of selection may be highly helpful for screening effective aptamers. Overall, our study provides novel insights for screening and developing effective aptamers for use as anti-influenza drugs.     

Improvement of liver function parameters in patients with type 2 diabetes treated with thiazolidinediones

To increase our understanding of the effect of thiazolidinediones, a new class of antidiabetic drugs, on liver function as well as glycemic control, we investigated liver function before, during, and after treatment with troglitazone and pioglitazone. A total of 32 patients with type 2 diabetes were studied. Glycemic control and liver function were measured before, during, and after 4 to 12 weeks of treatment with troglitazone or pioglitazone. Glycemic control was assessed by fasting levels of plasma glucose, hemoglobin A 1c , and serum insulin, and liver function was assessed by asparatate aminotransferase (AST), alanine aminotransferase (ALT), and gamma -glutamyl transpeptidase ( gamma-GTP). Homeostasis model assessment for insulin resistance was used as an index of insulin resistance. During treatment with troglitazone, fasting plasma glucose and hemoglobin A 1c levels and homeostasis model assessment for insulin resistance were significantly decreased. Serum AST, ALT, and gamma-GTP levels were significantly decreased during treatment (AST, -17.4%; ALT, -27.2%; gamma-GTP, -47.9%) and returned to pretreatment levels after 4 weeks of withdrawal of the drug. A similar tendency was observed during treatment with pioglitazone (AST, -4.7%; ALT, -16.4%; gamma-GTP, -30.8%). These data suggest that, in contrast to the deterioration of liver function reported in a small subset of patients treated with troglitazone, treatment with thiazolidinediones was associated with a decrease in serum transaminases in most patients. The improvement in liver function parameters known to be associated with fatty liver in the present study, together with an improvement in fatty liver reported for another class of insulin sensitizers, biguanides, suggests that thiazolidinediones may have a beneficial effect on fatty liver.     

Intraductal polypoid growth variant of pancreatic acinar cell carcinoma metastasizing to the intrahepatic bile duct 6 years after surgery: A case report and literature review

We present the first reported case of intraductal polypoid growth (IPG) variant of pancreatic acinar cell carcinoma (ACC) metastasizing to the intrahepatic bile duct. A 58-year-old Japanese woman had previously presented with obstructive jaundice and a 7.0 cm mass in the pancreatic head. She underwent biliary drainage for 2 months followed by pancreatectomy. Histological examination revealed a carcinoma with acinar pattern, immunohistochemically positive for trypsin, and acinar cell carcinoma was diagnosed. IPGs were prominent in the main pancreatic duct and its tributaries, extending into the intrapancreatic bile duct with tumor casts in the lumen. Imaging examinations 6 years later revealed a growing lesion within the intrahepatic bile duct. Needle biopsy examination suggested metastasis of ACC, and she underwent chemoradiation therapy and partial hepatectomy. Histological examination demonstrated ACC confined to the intrahepatic bile duct. The localization of metastasis and slow growth may indicate indolent biologic behavior of the IPG variant.     

Perineural Invasion in Extrahepatic Cholangiocarcinoma: Prognostic Impact and Treatment Strategies

Background

The significance of perineural invasion in extrahepatic cholangiocarcinoma has not been fully elucidated. This study aims to determine the prognostic impact of and optimal treatment strategy for perineural invasion in patients with extrahepatic cholangiocarcinoma.

Methods

Medical records of 133 patients with extrahepatic cholangiocarcinoma who underwent curative resection were reviewed retrospectively. Ninety-eight patients had perineural invasion and 35 patients did not. Univariate and multivariate survival analyses were performed to clarify the prognostic impact of and optimal treatment strategy for perineural invasion.

Results

Only tumor differentiation (P?=?0.024) was independently associated with perineural invasion in the multivariate logistic regression model. Multivariate survival analysis revealed that perineural invasion (P?=?0.002), resection margin status (P?=?0.016), and International Union Against Cancer (UICC) pT factor (P?=?0.015) were independent prognostic factors of overall survival. Overall 5-year survival rates for patients with and without perineural invasion were 28 and 74 %, respectively. Among 98 patients with perineural invasion, the use of adjuvant chemotherapy (P?=?0.003), lymph node status (P?=?0.015), resection margin status (P?=?0.008), and UICC pT factor (P?=?0.016) were independently associated with overall survival by multivariate analysis. Overall 5-year survival rates for patients with perineural invasion who did and did not receive adjuvant chemotherapy were 33 and 21 %, respectively (P?=?0.023).

Conclusions

Perineural invasion is a potent prognostic factor in extrahepatic cholangiocarcinoma. Adjuvant chemotherapy may improve the overall survival of patients with perineural invasion.