Somatic mutations in PIK3CA and activation of AKT in intraductal tubulopapillary neoplasms of the pancreas.

Intraductal tubulopapillary neoplasm (ITPN) is a recently recognized rare variant of intraductal neoplasms of the pancreas. Molecular aberrations underlying the neoplasm remain unknown. We investigated somatic mutations in PIK3CA, PTEN, AKT1, KRAS, and BRAF. We also investigated aberrant expressions of phosphorylated AKT, phosphatase and tensin homolog (PTEN), tumor protein 53 (TP53), SMAD4, and CTNNB1 in 11 cases of ITPNs and compared these data with those of 50 cases of intraductal papillary mucinous neoplasm (IPMN), another distinct variant of pancreatic intraductal neoplasms. Mutations in PIK3CA were found in 3 of 11 ITPNs but not in IPMNs (P = 0.005; Fisher exact test). In contrast, mutations in KRAS were found in none of the ITPNs but were found in 26 of the 50 IPMNs (P = 0.001; Fisher exact test). PIK3CA mutations were associated with strong expression of phosphorylated AKT (P < 0.001; the Mann-Whitney U test). Moreover, the expression of phosphorylated AKT was apparent in most ITPNs but only in a few IPMNs (P < 0.001; the Mann-Whitney U test). Aberrant expressions of TP53, SMAD4, and CTNNB1 were not statistically different between these neoplasms. Mutations in PIK3CA and the expression of phosphorylated AKT were not associated with age, sex, tissue invasion, and patients' prognosis in ITPNs. These results indicate that activation of the phosphatidylinositol 3-kinase pathway may play a crucial role in ITPNs but not in IPMNs. In contrast, the mutation in KRAS seems to play a major role in IPMNs but not in ITPNs. The activated phosphatidylinositol 3-kinase pathway may be a potential target for molecular diagnosis and therapy of ITPNs.

One-step percutaneous transhepatic insertion of a balloon-expanding metallic stent for obstructive jaundice.

BACKGROUND AND AIM: The aim of this study was to evaluate the efficacy and safety of one-step percutaneous transhepatic insertion of the Express LD stent, a balloon-expanding stainless steel stent used for the management of distal artery stenosis in the treatment of obstructive jaundice caused by various inoperable malignancies. METHODS: Seventy-one consecutive patients with unresectable malignant biliary obstruction who underwent Express LD stent placement between 2007 and 2010 at our institute were reviewed. RESULTS: Mean stent patency was 165 ± 144 days and mean patient survival was 180 ± 156 days, while the cumulative stent patency rate and patient survival rate at 6 and 12 months were 79% and 65%, and 38% and 16%, respectively. Stents were successfully placed in all cases without any stent migration or misplacement. Stent failure occurred in 14 patients (20%), and 16 complications were observed, including 12 cholangitis (17%), two cholecysitis (3%), and two pancreatitis (3%). Y-configuration stenting for hilar bile duct obstruction was the only independent prognostic factor for stent failure. CONCLUSIONS: One-step percutaneous transhepatic insertion of the Express LD stent is effective and safe for the management of obstructive jaundice caused by inoperable malignancies.

Left hepatic trisectionectomy for hilar cholangiocarcinoma presenting with an aberrant biliary duct of segment 5: a case report.

INTRODUCTION: Management of the biliary ducts during liver resection is one of the most important challenges for hepatobiliary surgeons. Here, we report the case of a left hepatic trisectionectomy for hilar cholangiocarcinoma with a rare aberrant biliary duct of segment 5, which, to the best of our knowledge, has never been reported in previous literature. CASE PRESENTATION: A 56-year-old Asian female initially presented with intrahepatic bile duct dilatation in the left lateral sector, left paramedian sector, and right paramedian sector. Simultaneous cholangiography from a percutaneous transhepatic biliary drainage tube in biliary duct of segment 8 and endoscopic nasobiliary drainage tube in biliary duct of segment 3 revealed drainage of the right lateral sectoral branch into the common hepatic duct and the aberrant drainage of segment 5 into the right lateral sectoral branch. The left hepatic duct, right paramedian sectoral duct, and the confluence of the right lateral sectoral duct were narrowed. Left hepatic trisectionectomy was successfully performed with careful dissection and division of the aberrant biliary duct of segment 5. CONCLUSION: For safe liver resection, it is important to perform a detailed anatomic evaluation of the intrahepatic ducts, both preoperatively and intraoperatively.

Giant liver hemangioma resected by trisectorectomy after efficient volume reduction by transcatheter arterial embolization: a case report.

INTRODUCTION: Liver hemangiomas are the most common benign liver tumors, usually small in size and requiring no treatment. Giant hemangiomas complicated with consumptive coagulopathy (Kasabach-Merritt syndrome) or causing severe incapacitating symptoms, however, are generally considered an absolute indication for surgical resection. Here, we present the case of a giant hemangioma, which was, to the best of our knowledge, one of the largest ever reported. CASE PRESENTATION: A 38-year-old Asian man was referred to our hospital with complaints of severe abdominal distension and pancytopenia. Examinations at the first visit revealed a right liver hemangioma occupying the abdominal cavity, protruding into the right diaphragm up to the right thoracic cavity and extending down to the pelvic cavity, with a maximum diameter of 43 cm, complicated with "asymptomatic" Kasabach-Merritt syndrome. Based on the tumor size and the anatomic relationship between the tumor and hepatic vena cava, primary resection seemed difficult and dangerous, leading us to first perform transcatheter arterial embolization to reduce the tumor volume and to ensure the safety of future resection. The tumor volume was significantly decreased by two successive transcatheter arterial embolizations, and a conventional right trisectorectomy was then performed without difficulty to resect the tumor. CONCLUSIONS: To date, there have been several reports of aggressive surgical treatments, including extra-corporeal hepatic resection and liver transplantation, for huge hemangiomas like the present case, but because of its benign nature, every effort should be made to avoid life-threatening surgical stress for patients. Our experience demonstrates that a pre-operative arterial embolization may effectively enable the resection of large hemangiomas.

Risk factors for postoperative pancreatic fistula after pancreaticoduodenectomy: the significance of the ratio of the main pancreatic duct to the pancreas body as a predictor of leakage.

OBJECTIVE: Postoperative pancreatic fistula (POPF) is a severe and frequent complication after pancreaticoduodenectomy (PD). The aim of this study was to identify an independent predictor of POPF and to assess the efficacy of preoperative multidetector row computed tomography (MDCT) images as an indicator for POPF. METHODS: A total of 122 patients who underwent PD with an end-to-side, duct-to-mucosa pancreaticojejunostomy between January 2005 and May 2009 were retrospectively reviewed. The diameter of the main pancreatic duct (MPD), the diameter of the short axis of the pancreas body, and the ratio of the MPD to the pancreas body (MPD index) were digitally measured based on the curved reformatted images of preoperative MDCT. RESULTS: Postoperative pancreatic fistula occurred in 33 patients (27%). The operative mortality rate was 3.3% (4 patients). All four patients had grade C POPF. Three died because of hemorrhage from a pseudoaneurysm of the gastroduodenal artery stump, and one died because of sepsis due to major leakage from the pancreaticojejunostomy. In a multivariate analysis, the intraoperative blood loss (/100 ml) [odds ratio (OR), 1.1; 95% confidence interval (CI), 1.05-1.17] and MPD index (<0.2) (OR 50; 95% CI 6-41) proved to be independent predictors of POPF. In patients with an MPD index of <0.2, the incidence of POPF was 45%, and the mortality rate was 7.5%. CONCLUSION: The MPD index obtained from preoperative MDCT can be a reliable predictor of POPF after PD.

Modified liver-hanging maneuver designed to minimize blood loss during hepatic parenchymal transection in hemihepatectomy.

PURPOSE: We evaluated the efficiency of a modified liver-hanging technique for minimizing intraoperative blood loss during right and left hemihepatectomy. METHODS: The lower end of the hanging tape was repositioned between the parenchyma of the left paramedian sector and the hilar plate. The upper end of the tape was positioned between the right hepatic vein and middle hepatic vein for right hepatectomy (Belghiti), and between the middle hepatic vein and left hepatic vein for left hepatectomy. The tape was positioned prior to the parenchymal transection. We compared the results of this operative technique, performed in 15 recent patients, with those of conventional hemihepatectomy performed in 14 earlier patients. RESULTS: There were no intergroup differences in baseline characteristics or postoperative outcomes. Intraoperative blood loss (P = 0.02), especially blood loss during the parenchymal transection (P = 0.005), was significantly less in patients undergoing the modified technique. Multivariate analysis revealed that this modified liver-hanging technique offered a significant advantage in blood-loss reduction during parenchymal transection over the conventional techniques (P = 0.005). CONCLUSION: Using the liver-hanging technique during hemihepatectomy could be crucial for liver surgeons.

Diagnostic accuracy of multidetector-row computed tomography for hilar cholangiocarcinoma.

BACKGROUND AND AIM: The aim of this study was to investigate the diagnostic reliability of multidetector-row computed tomography (MDCT) for the evaluation of tumor spread in hilar cholangiocarcinoma. METHODS: Images obtained from a 16-detector row scanner of 22 patients were interpreted. The diagnostic accuracy of longitudinal ductal spread, vertical invasion (including hepatic parenchyma), and lymph node metastasis was assessed with reference to histopathological findings. RESULTS: The location of the tumor was correctly diagnosed in 95% of cases (21/22), but in five of these cases, the cut end of the intrahepatic bile duct was positive, resulting in 77% diagnostic accuracy for longitudinal spread. Among the patients with a negative bile duct surgical margin, there was a significant difference in the measurement of tumor spread between MDCT and microscopic investigation (P < 0.001). For vertical invasion, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MDCT were 69%, 100%, 100%, and 69% for the liver parenchyma, respectively. The sensitivity, specificity, PPV, and NPV of MDCT for lymph node metastasis were 50%, 75%, 43%, and 80%, respectively. CONCLUSIONS: The diagnostic accuracy of MDCT for tumor location and vertical invasion was satisfactory, but ductal spread was underestimated in comparison with microscopic measurements.

Preoperative evaluation of the longitudinal spread of extrahepatic bile duct cancer using multidetector computed tomography.

BACKGROUND/PURPOSE: The aim of this study was to compare the diagnostic accuracy of multidetector computed tomography (MDCT) and direct cholangiography in evaluating the longitudinal spread of extrahepatic bile duct cancer. METHODS: Images obtained from a 16-detector row scanner (MDCT) and from direct cholangiography (via either endoscopic naso-biliary drainage or percutaneous transhepatic biliary drainage) of 47 patients with histopathologically proven extrahepatic bile duct cancer were retrospectively interpreted. Differences between measures of longitudinal tumor spread determined by each modality and measures of macroscopic spread in resected specimens were assessed and compared. RESULTS: Assessments carried out using MDCT differed significantly less from the macroscopic measurements than those made using direct cholangiography (P < 0.0001). Provided the diagnosis was defined as being accurate, based on a diagnostic difference of within +/-5 mm, the diagnostic accuracy of MDCT (96%) was significantly higher than that of direct cholangiography (70%) (P = 0.028). Preoperative evaluation with direct cholangiography resulted in a 30% underestimation of the incidence. CONCLUSION: MDCT is superior to direct cholangiography for evaluating the preoperative longitudinal extent of bile duct cancer. Consequently, the utility of MDCT for preoperative evaluation of extrahepatic bile duct cancer warrants further examination.

Adult intussusception induced by the stump of the jejunal loop after liver transplantation.

Intussusception occurs rarely in adults compared with children, and in the case of adults, some organic disease, such as a benign or malignant tumor, can be found at the leading edge of the intussusception in about 90% of adult cases. This study reports a case of adult intussusception in which the stump of the jejunal loop in a Roux-en-Y bilioenteric reconstruction acted as a leading tip of the intussusception.

Hepato-pancreaticoduodenectomy with preservation of the collateral arterial arcade in the head of the pancreas in a patient with celiac axis stenosis.

Hepato-pancreaticoduodenectomy was performed for common bile duct carcinoma associated with celiac axis stenosis. To secure arterial blood flow to the upper abdominal organs, we preserved the anterior arcade in the pancreas head acting as a collateral pathway between the superior mesenteric artery and the celiac artery. This is another valid alternative procedure for pancreaticoduodenectomy in a patient with celiac axis stenosis.