Scheduled endoscopic treatment of biliary anastomotic and nonanastomotic strictures after orthotopic liver transplantation.

BACKGROUND AND AIMS: Biliary strictures after liver transplantation are associated with significant morbidity and mortality. Although various endoscopic treatment strategies are available, consensus on a particular strategy is lacking. Moreover, the influence of endoscopic therapy on overall survival has not been studied. This retrospective study aimed to evaluate the impact of scheduled endoscopic dilatation of biliary strictures after orthotopic liver transplantation on therapeutic success, adverse events, and survival. METHODS: Between 2000 and 2016, patients with post-transplant anastomotic and nonanastomotic strictures were treated with balloon dilatation at defined intervals until morphologic resolution and clinical improvement. The primary clinical endpoint was overall survival, whereas secondary outcomes were technical and sustained clinical success, adverse events, treatment failure, and recurrence. RESULTS: Overall, 165 patients with a mean follow-up of 8 years were included; anastomotic and nonanastomotic strictures were diagnosed in 110 and 55 patients, respectively. Overall survival was significantly higher in patients with anastomotic strictures than in those with nonanastomotic strictures (median, 17.6 vs 13.9 years; log-rank: P < .05). Sustained clinical success could be achieved significantly more frequently in patients with anastomotic strictures (79.1% vs 54.5%, P < .001), and such patients showed significantly superior overall survival (19.7 vs 7.7 years; log-rank: P < .001). Sustained clinical success and the presence of nonanastomotic strictures were independently associated with better and worse outcomes (P < .05), respectively. CONCLUSIONS: Scheduled endoscopic treatment of biliary anastomotic and nonanastomotic strictures after liver transplantation is effective and safe, with high success rates. The implementation of this strategy controls symptoms and significantly improves survival.

Mechanical stretching and chemical pyloroplasty to prevent delayed gastric emptying after esophageal cancer resection-a meta-analysis and review of the literature.

BACKGROUND: Delayed gastric emptying (DGE) occurs in up to 40% of patients after esophageal resection and prolongs recovery and hospital stay. Surgically pyloroplasty does not effectively prevent DGE. Recently published methods include injection of botulinum toxin (botox) in the pylorus and mechanical interventions as preoperative endoscopic dilatation of the pylorus. The aim of this study was to investigate the efficacy of those methods with respect to the newly published Consensus definition of DGE. METHODS: A systematic literature search using CENTRAL, Medline, and Web of Science was performed to identify studies that described pre- or intraoperative botox injection or mechanical stretching methods of the pylorus in patients undergoing esophageal resection. Frequency of DGE, anastomotic leakage rates, and length of hospital stay were analyzed. Outcome data were pooled as odd's ratio (OR) or mean difference using a random-effects model. Risk of bias was assessed using the Robins-I tool for non-randomized trials. RESULTS: Out of 391 articles seven retrospective studies described patients that underwent preventive botulinum toxin injection and four studies described preventive mechanical stretching of the pylorus. DGE was not affected by injection of botox (OR 0.87, 95% confidence interval [CI] 0.37-2.03, P = 0.75), whereas mechanical stretching resulted in significant reduction of DGE (OR 0.26, 95% CI 0.14-0.5, P < 0.0001). CONCLUSION: Mechanical stretching of the pylorus, but not injection of botox reduces DGE after esophageal cancer resection. A newly developed consensus definition should be used before the conduction of a large-scale randomized-controlled trial.

Self-Expanding Metal Stents for Anastomotic Leaks After Upper Gastrointestinal Cancer Surgery.

BACKGROUND: Anastomotic leakage (AL) is a common and severe complication after upper gastrointestinal (UGI) surgery. Although evidence is scarce, endoscopic deployed self-expanding metal stents (SEMS) are well-established for the management of AL in UGI surgery. The present study aimed to evaluate the feasibility, effectiveness, and safety of SEMS in terms of success, mortality, and morbidity in patients with AL after UGI cancer surgery. MATERIALS AND METHODS: Patients with AL after primary UGI cancer surgery were retrospectively analyzed with regard to demographics, disease, surgical and endoscopic procedures, and complications. Stent treatment success was divided into technical, primary (within 72 hours of stent deployment), sustained (after 72 hours of stent deployment), and sealing success. RESULTS: In a total of 63 patients, 74 stents were used and 11 were deployed in endoscopic reinterventions. Stent deployment was successful in all patients. Primary and sustained success rates were 68.3% (n = 43) and 65.1% (n = 41), respectively. Of the primarily successfully treated patients, 87.8% remained successfully treated. If primary treatment was unsuccessful, it remained unsuccessful in 66.6% of the patients (P = 0.002). Final sealing of the leakage was observed in 65.1% of patients (n = 41). Longer stent shafts and wider stent end widths were correlated with successful stent treatment (P < 0.05). CONCLUSION: SEMS are a safe and sufficient tool in the treatment of AL after UGI cancer surgery. Treatment success is improved with longer stent shafts and wider stent end widths. Switching to alternative treatments is strongly suggested if signs of persistent leakage are present beyond 72 hours after stent placement, as this is highly indicative of sustained stent failure.

Feasibility, effectiveness, and safety of endoscopic vacuum therapy for intrathoracic anastomotic leakage following transthoracic esophageal resection.

BACKGROUND: Anastomotic leakage (AL) in the upper gastrointestinal (GI) tract is associated with high morbidity and mortality rates. Especially intrathoracic anastomotic leakage leads to life-threatening complications. Endoscopic vacuum therapy (EVT) for anastomotic leakage after transthoracic esophageal resection represents a novel concept. However, sound clinical data are still scarce. This retrospective, single-center study aimed to evaluate the feasibility, effectiveness, and safety of EVT for intrathoracic anastomotic leakage following abdomino-thoracic esophageal resection. METHODS: From March 2014 to September 2019 259 consecutive patients underwent elective transthoracic esophageal resection. 72 patients (27.8%) suffered from AL. The overall collective in-hospital mortality rate was 3.9% (n = 10). Data from those who underwent treatment with EVT were included. RESULTS: Fifty-five patients were treated with EVT. Successful closure was achieved in 89.1% (n = 49) by EVT only. The EVT-associated complication rate was 5.4% (n = 3): bleeding occurred in one patient, while minor sedation-related complications were observed in two patients. The median number of EVT procedures per patient was 3. The procedures were performed at intervals of 3-5 days, with a 14-day median duration of therapy. The mortality rate of patients with AL was 7.2% (n = 4). Despite successfully terminated EVT, three patients died because of multiple organ failure, acute respiratory distress syndrome, and urosepsis (5.4%). One patient (1.8%) died during EVT due to cardiac arrest. CONCLUSIONS: EVT is a safe and effective approach for intrathoracic anastomotic leakages following abdomino-thoracic esophageal resections. It offers a high leakage-closure rate and the potential to lower leakage-related mortalities. TRIAL REGISTRATION: This trial was registered and approved by the Institutional Ethics Committee of the University of Heidelberg on 16.04.2014 (Registration Number: S-635/2013).

Sedation-related complications during anesthesiologist-administered sedation for endoscopic retrograde cholangiopancreatography: a prospective study.

BACKGROUND: Patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) require adequate sedation or general anesthesia. To date, there is lack of consensus regarding who should administer sedation in these patients. Several studies have investigated the safety and efficacy of non-anesthesiologist-administered sedation for ERCP; however, data regarding anesthesiologist-administered sedation remain limited. This prospective single-center study investigated the safety and efficacy of anesthesiologist-administered sedation and the rate of successful performed ERCP procedures. METHODS: The study included 200 patients who underwent ERCP following anesthesiologist-administered sedation with propofol and remifentanil. Procedural data, oxygen saturation, systolic blood pressure (SBP), heart rate, recovery score, patient and endoscopist satisfaction, as well as 30-day mortality and morbidity data were analyzed. RESULTS: Sedation-related complications occurred in 36 of 200 patients (18%) and included hypotension (SBP < 90 mmHg) and hypoxemia (O2 saturation < 90%) in 18 patients (9%) each. Most events were minor and did not necessitate discontinuation of the procedure. However, ERCP was terminated in 2 patients (1%) secondary to sedation-related complications. Successful cannulation was performed in all patients. The mean duration of the examination was 25 ± 16 min. Mean recovery time was 14 ± 10 min, and high post-procedural satisfaction was observed in both, patients (mean visual analogue scale [VAS] 9.6 ± 0.8) and endoscopists (mean VAS 9.3 ± 1.3). CONCLUSION: This study suggests that anesthesiologist-administered sedation is safe in patients undergoing ERCP and is associated with a high rate of successful ERCP, shorter procedure time, and more rapid post-anesthesia recovery, with high patient and endoscopist satisfaction.

Prognostic value of inflammatory markers for detecting anastomotic leakage after esophageal resection.

BACKGROUND: Early diagnosis of anastomotic leakage (AL) after esophageal resection is crucial for the successful management of this complication. Inflammatory serological markers are indicators of complications during the postoperative course. The aim of the present study was to evaluate the prognostic value of routine inflammatory markers to predict anastomotic leakage after transthoracic esophageal resection. METHODS: Data from all consecutive patients undergoing transthoracic esophageal resection between January 2010 and December 2016 were analyzed from a prospective database. Besides clinicodemographic parameters, C-reactive protein, white blood cell count and albumin were analyzed and the Noble/Underwood (NUn) score was calculated to evaluate their predictive value for postoperative anastomotic leakage. Diagnostic accuracy was measured by sensitivity, specificity, and negative and positive predictive values using area under the receiver operator characteristics curve. RESULTS: Overall, 233 patients with transthoracic esophageal resection were analyzed, 30-day mortality in this group was 3.4%. 57 patients (24.5%) suffered from AL, 176 patients were in the AL negative group. We found significant differences in WBCC, CRP and NUn scores between patients with and without AL, but the analyzed markers did not show an independent relevant prognostic value. For CRP levels below 155 mg/dl from POD3 to POD 7 the negative predictive value for absence of AI was > 80%. Highest diagnostic accuracy was detected for CRP levels on 4th POD with a cut-off value of 145 mg/l reaching negative predictive value of 87%. CONCLUSIONS: In contrast to their prognostic value in other surgical procedures, CRP, WBCC and NUn score cannot be recommended as independent markers for the prediction of anastomotic leakage after transthoracic esophageal resection. CRP is an accurate negative predictive marker and discrimination of AL and no-AL may be helpful for postoperative clinical management. Trial registration The study was approved by the local ethical committee (S635-2013).

Effect of scheduled endoscopic dilatation of dominant strictures on outcome in patients with primary sclerosing cholangitis.

OBJECTIVE: Scheduled endoscopic dilatation of dominant strictures (DS) in primary sclerosing cholangitis (PSC) might improve outcome relative to endoscopic treatment on demand, but evidence is limited. Since randomisation is difficult in clinical practice, we present a large retrospective study comparing scheduled versus on-demand endoscopic retrograde cholangiopancreatography (ERCP) based on patient preferences. DESIGN: Between 1987 and 2017, all new patients with PSC had been offered scheduled ERCP with dilatation of a DS if diagnosed; the latter was repeated at defined intervals until morphological resolution, independent of clinical symptoms (treatment group). Patients who refused participation were clinically evaluated annually and received endoscopic treatment only on demand (control group). The primary clinical endpoint was transplantation-free survival. Secondary outcomes were overall survival, bacterial cholangitis episodes, hepatic decompensation of liver cirrhosis and endoscopy-related adverse events. RESULTS: The final study included 286 patients, 133 (46.5%) receiving scheduled ERCP and 153 (53.5%) receiving on-demand ERCP. After a mean follow-up of 9.9 years, the rate of transplantation-free survival was higher in patients receiving scheduled ERCP (51% vs 29.3%; p<0.001), as was transplantation-free survival time (median: 17.9 vs 15.2 years; log-rank: p=0.008). However, the benefit of scheduled ERCP was significant only in patients with the initial (17.1%) or later (45.5%) diagnosis of a DS (17.8 vs 11.1 years; log-rank: p<0.001). IBD (p=0.03), DS (p=0.006), higher Mayo Risk Score (p=0.02) and non-adherence to scheduled endoscopy (p=0.005) were independently associated with transplantation-free survival. CONCLUSION: In our large retrospective study, regular ERCP with endoscopic balloon dilatation significantly benefits patients with PSC with DS, diagnosed both at initial presentation and during surveillance, even if asymptomatic. Further studies have to find out how to best identify stricture patients non-invasively.

Risk Factors Associated With Pouch Adenomas in Patients With Familial Adenomatous Polyposis.

BACKGROUND: Restorative proctocolectomy with ileal pouch-anal reconstruction is the standard prophylactic surgical procedure for patients with familial adenomatous polyposis. However, several groups have reported the development of adenomas and even carcinomas within the ileal pouch. The predisposing factor was the time interval after pouch surgery in some studies, but it was the severity of the initial colonic disease and duodenal adenomatosis in others. OBJECTIVE: The aim of this study was to further clarify the prevalence of pouch adenomas, clinical risk factors, and a possible phenotype-genotype relation in a large population of patients with familial adenomatous polyposis, as well as to analyze pouch adenoma-free survival. DESIGN: This study was designed as a cohort study. SETTINGS: This study was conducted in a specialized outpatient clinic at the University of Heidelberg. PATIENTS: A total of 192 patients with familial adenomatous polyposis were included, and all of the available endoscopy reports after pouch surgery were screened for pouch adenomas. Additional clinical information was retrieved from the Heidelberg Polyposis Register. MAIN OUTCOME MEASURES: This present study revealed 3 main independent risk factors for the development of pouch adenomas: age <18 years at the time of IPAA, male sex, and the presence of gastric adenomas. Secondary outcome measures were adenoma progression and overall pouch adenoma-free survival. RESULTS: Pouch adenomas were detected in 46.9% of patients. Median follow-up was 12.8 years (interquartile range, 9.0-17.0 y) for patients with pouch adenomas and 7.3 years (interquartile range, 2.5-12.2 y) for those without them. Patients underwent pouch surgery at a median age of 27.5 years (range, 10.2-58.5 y), and pouch adenomas occurred a median of 8.5 years (range, 0.9-25.1 y) after surgery. Also detected were gastric adenomas in 37.2%, duodenal adenomas in 80.3%, and desmoid tumors in 24.5% of patients. Estimation of pouch adenoma-free survival revealed that, after 20 years, only ≈22% of patients would be free of pouch adenomas. Male sex, age ≦18 years at the time of pouch surgery, and gastric adenomas were found to be independent risk factors for the development of pouch adenomas in a multivariate Cox regression analysis (p = 0.0002, p = 0.0059, and p = 0.0020). No predisposing germline mutation for pouch adenoma development was detected. LIMITATIONS: Detailed information on the initial preoperative findings was not fully available, and the study was only carried out as a single-center study. CONCLUSIONS: A severe upper intestinal phenotype, male sex, and age <18 years at the time of IPAA all increase the risk for development of pouch adenomas. See Video Abstract at http://links.lww.com/DCR/A675.

Laparoscopic transgastric circumferential stapler-assisted vs. endoscopic esophageal mucosectomy in a porcine model.

Background and study aims Extensive endoscopic mucosal resection (EMR) for Barrett's esophagus (BE) may lead to stenosis. Laparoscopic, transgastric, stapler-assisted mucosectomy (SAM) with the retrieval of a circumferential specimen is proposed. Methods SAM was evaluated in two phases. The feasibility of SAM and the quality of specimens were assessed in eight animals. The mucosal healing was evaluated in a 6-week survival experiment comparing SAM (n = 6) with EMR (n = 6). The ratio of the esophageal lumen width (REL) at the resection level measured on fluoroscopy at 6 weeks divided by the width immediately after resection was compared. Results In all animals, a circular mucosectomy specimen was successfully obtained, with a median area of 492 mm2 (interquartile range [IQR] 426 - 573 mm2) and 941 mm2 (IQR 813 - 1209 mm2) using a 21 mm and 25 mm stapler, respectively. In the survival experiments, symptomatic stenosis developed in two animals after EMR and in none after SAM. The REL was 0.27 (0.18 - 0.39) and 0.96 (0.9 - 1.04; P < 0.0001) for EMR and SAM, respectively. Conclusions SAM provides a novel technique for en bloc mucosectomy in BE. In contrast to EMR, mucosal healing after SAM was not associated with stenosis up to 6 weeks after intervention.

Location of a biliary leak after liver resection determines success of endoscopic treatment.

BACKGROUND: Bile leaks after hepatic resection are serious complications associated with substantial morbidity and mortality. The aim of this prospective observational study was to determine the therapeutic success of endoscopic treatment of biliary leakage after liver resection. PATIENTS AND METHODS: Grade B biliary leaks were considered for endoscopic treatment in patients after liver resection between 1/09 and 4/12. Endoscopic treatment (sphincterotomy only, plastic stent distal to leak or bridging) was defined as successful when the patient remained without symptoms after drain removal and without extravasation follow-up ERC 8 weeks later. RESULTS: Overall rate of biliary leak was 7.4 % (61/826). 35 patients with a grade B bile leak were considered for endoscopic treatment. 22 (63 %) had bile leaks that were peripherally located, and 13 (37 %) had bile leaks at central location. In 3 patients, sphincterotomy only was performed; in 19 patients, a stent distal to the leak and in 13 patients, a bridging stent was inserted. The overall success rate was 74 % (26/35 patients). Endoscopic treatment failed in 26 % (9/35), and mortality rate was 11 % (4/35). In all patients with leaks located at the right or left hepatic duct, treatment with the bridging stent was successful. CONCLUSION: Endoscopic therapy for biliary leakage after liver resection is safe and effective and should be considered as a first-line therapy in patients who are suitable for an interventional, non-surgical approach. Patients with a centrally located leak who are treated with a bridging stent are more likely to benefit from endoscopic intervention.

Significant decrease of mortality due to anastomotic leaks following esophageal resection: management makes the difference.

PURPOSE: Anastomotic leakage is the most frequent cause of postoperative mortality following esophageal surgery. However, no gold standard for diagnosing and managing leakage has been established. Continuous clinical judgment is extremely important; therefore, to optimize the management of leakage, we established a special group for decision-making in cases of suspected leakage in the early postoperative period. METHODS: Between January 2010 and December 2016, 234 consecutive patients underwent elective esophageal resection with a thoracoabdominal incision. In 2014, we established a group consisting of a surgeon, surgical endoscopist, and anesthesiologist for decision-making in cases of suspected leakage. They discussed emerging problems and decided on further diagnostics or therapy. The data were documented prospectively and compared to the years prior to 2014. RESULTS: Two hundred and thirty-four consecutive patients were enrolled in the study, 110 in the years 2010-2013 (group A), and 124 in the years 2014-2016 (group B). Neither patients' characteristics nor the rate of anastomotic leakage differed significantly between the two study groups. The hospital mortality rate was 10% (11 patients) in group A and 4.8% (six patients) in group B. Most interestingly, mortality due to anastomotic leakage was 35% in group A (9/26), whereas it decreased significantly to 6.5% (2/31 patients) (P < 0.001) in group B. CONCLUSIONS: Our data clearly demonstrated that optimizing the management of anastomotic leakage by making team decisions can lead to a significant decrease in mortality.

Role of endoscopy to predict a leak after esophagectomy.

PURPOSE: After esophageal surgery, many centers conduct a routine diagnostic test before reintroducing oral intake. However, the clinical value in asymptomatic patients has been questioned. Therefore, we left this decision to the discretion of the operating surgeon and documented the data prospectively. METHODS: Between 2007 and 2013, 185 consecutive patients underwent elective esophageal resection in our institution. The decision as to whether an endoscopy was to be performed as a routine-check or when a leak was clinically suspected was at the discretion of the operating surgeon. An immediate endoscopy was performed on emerging clinical signs of a leak. If a routine check was planned, it was performed between postoperative days 5-7. RESULTS: Of the 185 patients, 84 % had an endoscopy of the anastomosis during the hospital stay. Of the patients who underwent an endoscopy, 61 % were on a routine-check. In this group, one patient showed a leak at the time of endoscopy, 11 patients had pathological findings, 3 of these patients developed a leak later. Eighty-three patients had no pathological findings; nevertheless, 7 developed a leak later. In the on-demand-group, 10 patients showed a leak at the time of endoscopy. CONCLUSIONS: In a minority of patients, a routine-check of the anastomosis between days 5-7 revealed pathological findings that later led to an anastomotic leak (3/11). In contrast, a routine-check without pathological findings could not rule out the development of a future leak (7/83). Therefore, we conclude that routine postoperative studies to identify leaks after esophageal resection are not justified.

Progesterone rapidly down-regulates the biosynthesis of 5-lipoxygenase products in human primary monocytes.

5-Lipoxygenase (5-LO), the key enzyme in the biosynthesis of pro-inflammatory leukotrienes (LTs) from arachidonic acid, is regulated by androgens in human neutrophils and monocytes accounting for sex differences in LT formation. Here we show that progesterone suppresses the synthesis of 5-LO metabolites in human primary monocytes. 5-LO product formation in monocytes stimulated with Ca(2+)-ionophore A23187 or with lipopolysaccharide/formyl peptide was suppressed by progesterone at concentrations of 10-100 nM in cells from females and at 1 µM in cells from males. Progesterone down-regulated 5-LO product formation in a rapid and reversible manner, but did not significantly inhibit 5-LO activity in cell-free assays using monocyte homogenates. Also, arachidonic acid release and its metabolism to other eicosanoids in monocytes were not significantly reduced by progesterone. The inhibitory effect of progesterone on LTs was still observed when mitogen-activated protein kinases were pharmacologically blocked, stimulatory 1-oleoyl-2-acetyl-sn-glycerol was exogenously supplied, or extracellular Ca(2+) was removed by chelation. Instead, suppression of PKA by means of two different pharmacological approaches (i.e. H89 and a cell-permeable PKA inhibitor peptide) prevented inhibition of 5-LO product generation by progesterone, to a similar extent as observed for the PKA activators prostaglandin E2 and 8-Br-cAMP, suggesting the involvement of PKA. In summary, progesterone affects the capacity of human primary monocytes to generate 5-LO products and, in addition to androgens, may account for sex-specific effects on pro-inflammatory LTs.

12/15-lipoxygenase contributes to platelet-derived growth factor-induced activation of signal transducer and activator of transcription 3.

We showed previously that the small molecule indirubin-3'-monoxime (I3MO) prevents vascular smooth muscle cell (VSMC) proliferation by selectively inhibiting signal transducer and activator of transcription 3 (STAT3). Looking for the underlying upstream molecular mechanism, we here reveal the important role of reactive oxygen species (ROS) for PDGF-induced STAT3 activation in VSMC. We show that neither NADPH-dependent oxidases (Noxes) nor mitochondria, but rather 12/15-lipoxygenase (12/15-LO) are pivotal ROS sources involved in the redox-regulated signal transduction from PDGFR to STAT3. Accordingly, pharmacological and genetic interference with 12/15-LO activity selectively inhibited PDGF-induced Src activation and STAT3 phosphorylation. I3MO is able to blunt PDGF-induced ROS and 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE) production, indicating an inhibitory action of I3MO on 12/15-LO and consequently on STAT3. We identify 12/15-LO as a hitherto unrecognized signaling hub in PDGF-triggered STAT3 activation and show for the first time a negative impact of I3MO on 12/15-LO.

Kinetics of primary bile acids in patients after proctocolectomy and ileal pouch-anal anastomosis.

BACKGROUND: The high incidence of cholesterol gallstones in patients after proctocolectomy with ileal pouch-anal anastomosis (IPAA) may be due to an increased loss of bile acids. We aimed to evaluate the kinetics of the primary bile acids cholic acid (CA) and chenodeoxycholic acid (CDCA) in these patients. METHODS: Pool sizes, synthesis rates, and fractional turnover rates of CA and CDCA were determined by combined capillary gas chromatography/isotope ratio mass spectrometry in serum samples after administration of [¹³C]CA and [¹³C]CDCA in 6 patients and 9 healthy volunteers. RESULTS: In patients with IPAA, pool sizes of CA and CDCA were 11.5 (8.2-23.8) and 12.1 (6.7-20.1) µmol/kg, respectively, and were significantly lower than in healthy controls [36.0 (24-47) and 29.0 (21-42) µmol/kg, respectively; p < 0.05, each]. Fractional turnover rates of CA [1.19 (1.06-1.82) vs. 0.31 (0.13-0.54) per day] and CDCA [1.01 (0.50-1.63) vs. 0.23 (0.09-0.36) per day] were increased fourfold in patients with IPAA (p < 0.05, each). Synthesis rates of CDCA [10.2 (5.2-32.9) vs. 6.6 (2.7-10.5) µmol/kg per day, p = 0.05] and CA [15.1 (9.3-39.4) vs. 11.5 (3.1-20.5) µmol/kg per day, n.s.] tended to be higher in patients with IPAA than in controls. CONCLUSION: The reduced pool size of primary bile acids may contribute to the high incidence of cholesterol gallstones in patients after proctocolectomy and IPAA.

Radiologic versus endoscopic evaluation of the conduit after esophageal resection: a prospective, blinded, intraindividually controlled diagnostic study.

BACKGROUND: Anastomotic leakage is a major complication in esophageal surgery. Although contrast swallow is performed by many surgical centers before reintroduction of oral intake to exclude anastomotic leakage postoperatively, endoscopy is increasingly used in this situation and may be superior. This study compares radiographic contrast study and endoscopy for the identification of local complications after subtotal esophagectomy. METHODS: Between January 2006 and September 2007, a prospective, blinded, intraindividually controlled study was conducted in patients who underwent transthoracic esophagectomy due to esophageal cancer. A radiographic contrast study was performed prior to endoscopy on postoperative day 5-7. Technical feasibility, sensitivity, and specificity of the radiologic and endoscopic evaluations of the esophageal substitute were described. RESULTS: Radiographic contrast study was possible in only 64% of the patients (35 of 55). The contrast study could not be performed in 20 patients due to contraindications or mechanical ventilation. Endoscopy could be performed in all patients (p < 0.001). Pathologic findings were detected in 13 patients by endoscopy but in only 1 patient by contrast swallow. Leakage of the anastomosis or the conduit was correctly detected in 7 patients by endoscopy but in only 1 patient by contrast swallow (p = 0.01). Endoscopy detected focal conduit necrosis or ischemia in six additional patients. Contrast studies showed false-positive results in two patients. Both sensitivity and specificity of endoscopy were 100%, while sensitivity and specificity of the contrast study were only 20 and 94%. No complications resulted from postoperative endoscopy or radiologic imaging. CONCLUSIONS: Endoscopic evaluation of the esophageal substitute in the early postoperative course is possible in all patients without complications. Endoscopy is superior to the contrast study in detecting pathological findings after esophageal reconstruction. Radiologic contrast swallow in the early postoperative days is often not possible, has no further relevance, and should be replaced by endoscopic evaluation.

Navigation system for minimally invasive esophagectomy: experimental study in a porcine model.

BACKGROUND: Navigation systems potentially facilitate minimally invasive esophagectomy and improve patient outcome by improving intraoperative orientation, position estimation of instruments, and identification of lymph nodes and resection margins. The authors' self-developed navigation system is highly accurate in static environments. This study aimed to test the overall accuracy of the navigation system in a realistic operating room scenario and to identify the different sources of error altering accuracy. METHODS: To simulate a realistic environment, a porcine model (n = 5) was used with endoscopic clips in the esophagus as navigation targets. Computed tomography imaging was followed by image segmentation and target definition with the medical imaging interaction toolkit software. Optical tracking was used for registration and localization of animals and navigation instruments. Intraoperatively, the instrument was displayed relative to segmented organs in real time. The target registration error (TRE) of the navigation system was defined as the distance between the target and the navigation instrument tip. The TRE was measured on skin targets with the animal in the 0° supine and 25° anti-Trendelenburg position and on the esophagus during laparoscopic transhiatal preparation. RESULTS: On skin targets, the TRE was significantly higher in the 25° position, at 14.6 ± 2.7 mm, compared with the 0° position, at 3.2 ± 1.3 mm. The TRE on the esophagus was 11.2 ± 2.4 mm. The main source of error was soft tissue deformation caused by intraoperative positioning, pneumoperitoneum, surgical manipulation, and tissue dissection. CONCLUSION: The navigation system obtained acceptable accuracy with a minimally invasive transhiatal approach to the esophagus in a realistic experimental model. Thus the system has the potential to improve intraoperative orientation, identification of lymph nodes and adequate resection margins, and visualization of risk structures. Compensation methods for soft tissue deformation may lead to an even more accurate navigation system in the future.

Pharmacophore-based discovery of a novel cytosolic phospholipase A(2)α inhibitor.

The release of arachidonic acid, a precursor in the production of prostaglandins and leukotrienes, is achieved by activity of the cytosolic phospholipase A(2)α (cPLA(2)α). Signaling mediated by this class of bioactive lipids, which are collectively referred to as eicosanoids, has numerous effects in physiological and pathological processes. Herein, we report the development of a ligand-based pharmacophore model and pharmacophore-based virtual screening of the National Cancer Institute (NCI) database, leading to the identification of 4-(hexadecyloxy)-3-(2-(hydroxyimino)-3-oxobutanamido)benzoic acid (NSC 119957) as cPLA(2)α inhibitor in cell-free and cell-based in vitro assays.

Identification of new γ-hydroxybutenolides that preferentially inhibit the activity of mPGES-1.

Microsomal prostaglandin E(2) synthase-1 (mPGES-1) has been recognized as novel, promising drug target for anti-inflammatory and anticancer drugs. mPGES-1 catalyzes the synthesis of the inducible prostaglandin E(2) in response to pro-inflammatory stimuli, rendering this enzyme extremely interesting in drug discovery process owing to the drastic reduction of the severe side effects typical for traditional non-steroidal anti-inflammatory drugs. In the course of our investigations focused on this topic, we identified two interesting molecules bearing the γ-hydroxybutenolide scaffold which potently inhibit the activity of mPGES-1. Notably, the lead compound 2c that inhibited mPGES-1 with IC(50) = 0.9 µM, did not affect other related enzymes within the arachidonic acid cascade.

Impact of pretherapeutic routine clinical staging for the individualization of treatment in gastric cancer patients.

PURPOSE: The usefulness and prognostic impact of a pretherapeutic clinical staging is still a matter of discussion. However, a pretherapeutic estimation of the prognosis would be essential to adjust the patient's therapy. Our aim was to compare clinical and histopathological staging and to analyze the predictive value of routine clinical staging and its significance for the individualization of treatment. PATIENTS AND METHODS: We analyzed the data of 368 patients treated with gastric cancer in the University of Heidelberg, Department of Surgery, from January 2001 to June 2009. Pretherapeutic parameters including sex, age, cTNM, grading, Laurén classification, tumor localization, as well as posttherapeutic parameters were analyzed, and their impact for survival was evaluated. Follow-up data was obtained for all patients (2.17% lost to follow-up). RESULTS: The overall accuracy was 64.1% for pT category, 54.5% for pN category, and 80.3% for M category for the primary resected patients. For the patients treated neoadjuvantly, the overall accuracy was 21.8% for the pT category, 58.0% for the pN category, and 80.0% for the M category. The prognosis was associated to the age (p = 0.017), tumor localization (p < 0.001), grading (p = 0.041), cT category (p < 0.001), cN category (p < 0.001), and cM category (p = 0.001). The multivariate analysis, including pre- and postoperative factors, revealed tumor localization (p = 0.002), cN category (p = 0.019), and metastatic lymph node rate (p < 0.001) as independent prognostic factors. CONCLUSION: The accordance between clinical and histopathological staging is limited, but nevertheless pretherapeutic parameters have a high prognostic impact and could be used for individualized therapy planning. The relevant pretherapeutic prognostic factors can all be determined by routine clinical staging including CT and endoscopy. Consequently pretherapeutic prognostic evaluation and therapy planning seem to be feasible with routine staging methods.