Baki Topal

Laparoscopic liver resection of benign liver tumors: Results of a multicenter European experience

Objective: The objective of this study was to assess the feasibility, safety, and outcome of laparoscopic liver resection for benign liver tumors in a multicenter setting. Background: Despite restrictive, tailored indications for resection in benign liver tumors, an increasing number of articles have been published concerning laparoscopic liver resection of these tumors. Methods: A retrospective study was performed in 18 surgical centres in Europe regarding their experience with laparoscopic resection of benign liver tumors. Detailed standardized questionnaires were used that focused on patients characteristics, clinical data, type and characteristics of the tumor, technical details of the operation, and early and late clinical outcome. Results: From March 1992 to September 2000, 87 patients suffering from benign liver tumor were included in this study: 48 patients with focal nodular hyperplasia (55%), 17 patients with liver cell adenoma (21%), 13 patients with hemangioma (15%), 3 patients with hamartoma (3%), 3 patients with hydatid liver cysts (3%), 2 patients with adult polycystic liver disease (APLD) (2%), and 1 patient with liver cystadenoma (1%). The mean size of the tumor was 6 cm, and 95% of the tumors were located in the left liver lobe or in the anterior segments of the right liver. Liver procedures included 38 wedge resections, 25 segmentectomies, 21 bisegmentectomies (including 20 left lateral segmentectomies), and 3 major hepatectomies. There were 9 conversions to an open approach (10%) due to bleeding in 45% of the patients. Five patients (6%) received autologous blood transfusion. There was no postoperative mortality, and the postoperative complication rate was low (5%). The mean postoperative hospital stay was 5 days (range, 2–13 days). At a mean follow-up of 13 months (median, 10 months; range, 2–58 months), all patients are alive without disease recurrence, except for the 2 patients with APLD. Conclusions: Laparoscopic resection of benign liver tumors is feasible and safe for selected patients with small tumors located in the left lateral segments or in the anterior segments of the right liver. Despite the use of a laparoscopic approach, selective indications for resection of benign liver tumors should remain unchanged. When performed by expert liver and laparoscopic surgeons in selected patients and tumors, laparoscopic resection of benign liver tumor is a promising technique.

Patterns of recurrence after curative resection of pancreatic ductal adenocarcinoma

AIMS Despite curative surgery for pancreatic ductal adenocarcinoma (PDAC), most patients develop cancer recurrence and die from metastatic disease. Understanding of the patterns of failure after surgery can lead to new insights for novel therapeutic modalities. The aim of the present study is to describe the patterns of recurrence after curative resection of PDAC. METHODS A retrospective analysis was performed of 145 consecutive resections for PDAC between 1998 and 2005 (M/F 75/70; median (range) age 67 years (32-85 y)). The location of the first and consecutive recurrences, and the time interval to cancer recurrence after surgical resection was studied. The magnitude of tumour-free margin was less than a millimetre in 48 patients, whereas a positive surgical margin was observed in 27 patients. The median duration of follow-up was 18.5 (range 0.3-116.8) months. RESULTS Cancer recurrence was observed in 110 patients. The first location of recurrence was locoregional in 19, extra-pancreatic in 66, and combined locoregional and extra-pancreatic in 25 patients. Extra-pancreatic recurrence developed in the liver in 57, peritoneal in 35, pulmonary in 15, and retroperitoneal in 5 patients. The median (95% CI) overall (OS) and disease-free (DFS) survival was 18.7 (15.7-23.5) and 9.8 (7.5-12.4) months, respectively. The type of cancer recurrence did not significantly influence OS, while the resection margin status had a prognostic effect. CONCLUSION The vast majority of patients who undergo potentially curative surgery for PDAC develop cancer recurrence located in the abdominal cavity. Surgical resection margins with tumour involvement and tumour-free margins of less then 1mm are negative prognostic factors. Further research on better local surgical control, peri-operative locoregional treatment, and more effective adjuvant systemic therapy is necessary to improve long-term survival of patients with curable PDAC.

Pancreaticojejunostomy versus pancreaticogastrostomy reconstruction after pancreaticoduodenectomy for pancreatic or periampullary tumours: a multicentre randomised trial

BACKGROUND Postoperative pancreatic fistula is the leading cause of death and morbidity after pancreaticoduodenectomy. However, the best reconstruction method to reduce occurrence of fistula is debated. We did a multicentre, randomised superiority trial to compare the outcomes of different reconstructive techniques in patients undergoing pancreaticoduodenectomy for pancreatic or periampullary tumours. METHODS Patients aged 18-85 years with confirmed or suspected neoplasms of the pancreas, distal bile duct, ampulla vateri, duodenum, or periampullary tumours were eligible for inclusion. An internet-based platform was used to randomly assign patients to either pancreaticojejunostomy or pancreaticogastrostomy as reconstruction after pancreaticoduodenectomy, using permuted blocks with six patients per block. Within each centre the randomisation was stratified on the pancreatic duct diameter (≤3 mm vs >3 mm) measured at the time of surgery. The primary endpoint was the occurrence of clinical postoperative pancreatic fistula (grade B or C) as defined by the International Study Group on Pancreatic Fistula. The study was not masked and analyses were done by intention to treat. Patient follow-up was closed 2 months after discharge from the hospital. This study is registered with ClinicalTrials.gov, number NCT00830778. FINDINGS Between June, 2009, and August, 2012, we randomly allocated 167 patients to receive pancreaticojejunostomy and 162 to receive pancreaticogastrostomy. 33 (19.8%) patients in the pancreaticojejunostomy group and 13 (8.0%) in the pancreaticogastrostomy group had clinical postoperative pancreatic fistula (OR 2.86, 95% CI 1.38-6.17; p=0.002). The overall incidence of postoperative complications did not differ significantly between the groups (99 in the pancreaticojejunostomy group vs 100 in the pancreaticogastrostomy group), although more events in the pancreaticojejunostomy group were of grade ≥3a than in the pancreaticogastrostomy group (39 vs 35). INTERPRETATION In patients undergoing pancreaticoduodenectomy for pancreatic head or periampullary tumours, pancreaticogastrostomy is more efficient than pancreaticojejunostomy in reducing the incidence of postoperative pancreatic fistula. FUNDING Funding Johnson & Johnson Medical Devices, Belgium.

Histological Diversity in Cholangiocellular Carcinoma Reflects the Different Cholangiocyte Phenotypes

Cholangiocellular carcinoma (CC) originates from topographically heterogeneous cholangiocytes. The cylindrical mucin‐producing cholangiocytes are located in large bile ducts and the cuboidal non–mucin‐producing cholangiocytes are located in ductules containing bipotential hepatic progenitor cells (HPCs). We investigated the clinicopathological and molecular features of 85 resected CCs (14 hilar CCs [so‐called Klatskin tumor], 71 intrahepatic CCs [ICCs] including 20 cholangiolocellular carcinomas [CLCs], which are thought to originate from HPCs]) and compared these with the different cholangiocyte phenotypes, including HPCs. Immunohistochemistry was performed with biliary/HPC and hepatocytic markers. Gene expression profiling was performed in different tumors and compared with nonneoplastic different cholangiocyte phenotypes obtained by laser microdissection. Invasion and cell proliferation assay were assessed using different types of CC cell lines: KMC‐1, KMCH‐1, and KMCH‐2. Among 51 ICCs, 31 (60.8%) contained only mucin‐producing CC features (muc‐ICCs), whereas 39.2% displayed histological diversity: focal hepatocytic differentiation and ductular areas (mixed‐ICCs). Clinicopathologically, muc‐ICCs and hilar CCs showed a predominantly (peri‐)hilar location, smaller tumor size, and more lymphatic and perineural invasion compared with mixed‐ICCs and CLCs (predominantly peripheral location, larger tumor size, and less lymphatic and perineural invasion). Immunoreactivity was similar in muc‐ICCs and hilar CCs and in mixed‐ICCs and CLCs. S100P and MUC1 were significantly up‐regulated in hilar CCs and muc‐ICCs compared with mixed‐ICCs and CLCs, whereas NCAM1 and ALB tended to be up‐regulated in mixed‐ICCs and CLCs compared with other tumors. KMC‐1 showed significantly higher invasiveness than KMCH‐1 and KMCH‐2. Conclusion: Muc‐ICCs had a clinicopathological, immunohistochemical, and molecular profile similar to that of hilar CCs (from mucin‐producing cholangiocytes), whereas mixed‐ICCs had a profile similar to that of CLCs (thought to be of HPC origin), possibly reflecting their respective cells of origin. (HEPATOLOGY 2012;55:1876–1888)

Keratin 19: a key role player in the invasion of human hepatocellular carcinomas

Objective Keratin (K)19, a biliary/hepatic progenitor cell (HPC) marker, is expressed in a subset of hepatocellular carcinomas (HCC) with poor prognosis. The underlying mechanisms driving this phenotype of K19-positive HCC remain elusive. Design Clinicopathological value of K19 was compared with EpCAM, and α-fetoprotein, in a Caucasian cohort of 242 consecutive patients (167 surgical specimens, 75 needle biopsies) with different underlying aetiologies. Using microarrays and microRNA profiling the molecular phenotype of K19-positive HCCs was identified. Clinical primary HCC samples were submitted to in vitro invasion assays and to side population analysis. HCC cell lines were transfected with synthetic siRNAs against KRT19 and submitted to invasion and cytotoxicity assays. Results In the cohort of surgical specimens, K19 expression showed the strongest correlation with increased tumour size (p<0.01), decreased tumour differentiation (p<0.001), metastasis (p<0.05) and microvascular invasion (p<0.001). The prognostic value of K19 was also confirmed in a set of 75 needle biopsies. Profiling showed that K19-positive HCCs highly express invasion-related/metastasis-related markers (eg, VASP, TACSTD2, LAMB1, LAMC2, PDGFRA), biliary/HPC markers (eg, CD133, GSTP1, NOTCH2, JAG1) and members of the miRNA family 200 (eg, miR-141, miR-200c). In vitro, primary human K19-positive tumour cells showed increased invasiveness, and reside in the chemoresistant side population. Functionally, K19/KRT19 knockdown results in reduced invasion, loss of invadopodia formation and decreased resistance to doxorubicin, 5-fluorouracil and sorafenib. Conclusions Giving the distinct invasive properties, the different molecular profile and the poor prognostic outcome, K19-positive HCCs should be considered as a seperate entity of HCCs.

Effect of centralization of pancreaticoduodenectomy on nationwide hospital mortality and length of stay

Despite the persistence of large differences in operative mortality rates between centres, the value of centralization of pancreaticoduodenectomy (PD) remains under debate. This cohort study analysed the effect of centralization of PD on nationwide hospital mortality and length of hospital stay in Belgium.

Laparoscopic intrahepatic Glissonian approach for right hepatectomy is safe, simple, and reproducible

BackgroundHemorrhage from portal and hepatic veins is a major concern with laparoscopic right hepatectomy (LRH). The standard hilar approach is dissection of the portal pedicle outside the liver parenchyma with separate transection of the right hepatic artery, portal vein, and bile duct [1–5, 7, 9]. Variations in anatomy can hamper vascular and biliary control. The intrahepatic Glissonian access avoids these risks by en masse ligation of the portal structures without dissection for each separately [6, 8]. This technique was performed laparoscopically for the last 2 among 10 LRHs, and the results are presented.MethodsTotal LRH was performed under ultrasound assistance for two patients with malignancy. After lymph node sampling at the hepatoduodenal ligament, dissection was started with the incision of liver parenchyma posterior and anterior to the hilum, then continued outside the portal pedicle bifurcation toward the right and left sheaths. An endoscopic vascular stapling device was placed to transect the right portal pedicle en masse under direct laparoscopic vision and cholangiography guidance. Parenchymal transection and vascular control of the right hepatic vein was accomplished with harmonic scalpel, cavitron ultrasonic aspirator, bipolar diathermy, clips, and endoscopic stapling device, as appropriate. No Pringle’s maneuver was used. The specimen was extracted through a suprapubic incision using an endobag.ResultsThe operative times for the two patients were, respectively, 180 and 240 min. No blood loss occurred during the intrahepatic Glissonian dissection. Intraoperative blood loss (from the right hepatic vein) of 700 and 800 ml, respectively, was controlled laparoscopically. The postoperative periods were uneventful, with discharge, respectively, on days 6 and 7. The surgical resection margins were free of tumor.ConclusionsThe laparoscopic intrahepatic Glissonian approach used for right hepatectomy is safe, simple, and reproducible. It facilitates the hepatic hilar dissection with minimal operative risk. Further implementation of this technique is encouraged to improve the outcome for patients undergoing laparoscopic liver resection.

Systemic treatment of pancreatic cancer.

Patients with pancreatic cancer have a poor prognosis although systemic treatment has slightly improved the outcome for those with advanced pancreatic cancer, The approach to a patient with pancreatic cancer remains a great challenge. Patients often present with advanced disease and many are already in poor general condition at the time of diagnosis. Today, surgery remains the only curative therapeutic option. A small number of pancreatic adenocarcinomas, however, are resectable and relapses after surgery are very frequent. The reference treatment in patients with metastatic pancreatic cancer is gemcitabine. The median survival of patients with advanced pancreatic cancer who are treated with gemcitabine is approximately 6 months and only approximately 20% of patients will be alive at 1 year. Combinations of gemcitabine with new cytotoxic agents and with novel targeted agents hold the promise for improving the outcome. Randomized phase III studies are, however, still ongoing. Since most patients will relapse after complete surgical resection of pancreatic cancer, a search for a better adjuvant or neoadjuvant treatment is important. Although several randomized studies have suggested an improved outcome for a postoperative chemoradiotherapy or chemotherapy, the role of an adjuvant treatment remains today controversial. Randomized phase III studies are ongoing. A neoadjuvant strategy might therefore also play a role, but phase III studies are lacking. The systematic evaluation of new drugs in well designed clinical trials and the search for new molecular targets for treatment are crucial in our aim to improve the outcome for patients with pancreatic cancer.

Role of cancer stem cells in pancreatic ductal adenocarcinoma

As our understanding of pancreatic cancer evolves, evidence is growing to support a role for cancer stem cells in this devastating disease. Cancer stem cells constitute a distinct subpopulation in the tumor and are considered to drive both tumorigenesis and metastasis; these cells are thought to be highly resistant to standard treatment modalities. Here we review the current knowledge on pancreatic cancer stem cells and the implementation of cancer stem cell markers as prognostic or predictive biomarkers. We also discuss prospects for the use of cancer stem cells as targets for future therapeutic regimens in pancreatic cancer.

Perioperative cancer cell dissemination detected with a real-time RT-PCR assay for EpCAM is not associated with worse prognosis in pancreatic ductal adenocarcinoma

BackgroundEpithelial cell adhesion molecule (EpCAM) has been used as surrogate marker for the quantification of circulating tumour cells (CTC). Our aim was to prospectively study the value of a real-time RT-PCR assay for EpCAM detection in the peripheral blood and peritoneal cavity of patients undergoing pancreatectomy for pancreatic ductal adenocarcinoma (PDAC).MethodsFrom 48 patients with PDAC (40 resectable, 8 unresectable) and 10 patients with chronic pancreatitis undergoing pancreatectomy 10 ml of venous blood was drawn preoperatively (PB) and postoperatively (POB, day 1 (D1B), day 7 (D7B) and after 6 weeks (6WB). Of all patients undergoing pancreatectomy, 40 ml peritoneal lavage fluid was taken preoperatively and postoperatively. A real-time RT-PCR assay (TaqMan, ABI Prism 7700) was developed for the detection of EpCAM mRNA. To discriminate between EpCAM-positive and negative samples a cut-off was applied. Median postoperative follow-up was 24.0 months (range: 0.7 - 41.3).ResultsPB was EpCAM-positive (+) in 25% of patients versus 65% of patients in POB (p < 0.0001). EpCAM(+) was noted at D1B, D7B and 6WB was found in 28.6%, 23.1% and 23.5% of patients respectively. Preoperative peritoneal lavage fluid was EpCAM(+) in 10.3% versus 53.8% of patients postoperatively (p < 0.0001).At none of the time-points, an association was found between EpCAM positivity in blood and/or peritoneal cavity and cancer-specific or disease-free survival. Also, no significant associations were found between clinicopathological variables and perioperative EpCAM positivity.ConclusionsDespite a significant increase in EpCAM counts in postoperative blood and peritoneal lavage fluid this was not associated with worse prognosis after pancreatectomy for PDAC.Trial registrationClinicaltrials.gov NCT00495924