Bettina Rau

Treatment of Pancreatic Cancer: Challenge of the Facts

Adenocarcinoma of the pancreas is associated with the worst survival of any form of gastrointestinal malignancy. In spite of the progress in surgical treatment, resulting in increasing resection rates and a decrease in treatment-related morbidity and mortality, the true figures of cure are even today below 3%. The dissemination of pancreatic cancer behind the local tissue compartments restricts the short-term (< 3 years) and long-term outcome for patients who have undergone resection. By histological evaluation, less than 15% of the patients undergoing R0 resection have a pN0 status, more than 60% suffer from lymph angiosis carcinomatosa, and more than 50% suffer extrapancreatic nerve plexus infiltration. Hematoxylin and eosin–negative lymph nodes were found to be cancer positive when reverse transcriptase polymerase chain reaction (RT- PCR) or immunostaining was applied to the HE-negative lymph nodes. Cancer of the uncinate process has a very poor prognosis because there are no early symptoms; vessel wall involvement occurs early and frequently; a high association of liver metastasis exists as well. Surgery offers a low success rate, but it provides the only chance of cure. Ductal pancreatic cancer is diagnosed in more than 95% of the cases in an advanced stage; potentially curative resection can be performed only in about 10%–15% of these patients. Major contributions of surgery to improved treatment results are the reduction of surgical morbidity—e.g., early postoperative local and systemic complications—and a decrease of hospital mortality below 3%–5%. In most recently published prospective trials, R0 resection has been reported to result in an increase in short-term survival beyond that recorded for patients with residual tumor. However, R0 resection fails to improve long-term survival. In many published R0 series, standard tissue resection of pancreatic head cancer with the Kausch-Whipple procedure failed to include remote cancer cell–positive tissues in the operative specimen; e.g., N2-lymph nodes, nerve plexus, and perivascular extrapancreatic and retropancreatic tissues were not excised. Cancer recurrence after so-called R0 resection with curative intent is frequently the consequence of cancer left behind. Thus, long-term survival (> 5 years) is observed in a very small group of patients, contradicting the published 5-year actuarial survival rates of 20%–45% for resected patients. The assessment of clinical benefit from surgical or medical cancer treatment should therefore be based on several end points, not only on actuarial survival. Publication of actuarial survival figures must include the number of observed (actual) survivals, the definition of the subset of patients followed after resection, and the total number of patients in the study group; anything less is misleading. In reporting pancreatic cancer treatment trial results after oncological resections, more convincing primary end points to evaluate treatment efficacy are median survival (in months), actual survival at 1–5 years, and progression-free survival (in months). In series with multimodality treatment, clinical benefit response as well as quality of life measurements using the EORTC Quality of Life index C30 (QLQ-C30) are of importance in evaluating survival data. Adjuvant treatment improves survival after oncological resection; however, the short-term and long-term benefit after adjuvant chemotherapy in R0 as well as in R1-2 resected patients has not yet been underscored by data from controlled clinical trials. The survival benefit (median survival time) of adjuvant chemotherapy or radiochemotherapy has been demonstrated to be 6–10 months. Therefore, after oncological resection of pancreatic cancer each patient should be offered adjuvant treatment. A neoadjuvant treatment protocol for pancreatic cancer, however, has not been established.

Early severe acute pancreatitis: characteristics of a new subgroup.

This study focuses on patients with severe acute pancreatitis complicated by organ failure within the initial phase of the disease. Data of 158 patients with severe acute pancreatitis (SAP) admitted to hospital within 72 hours after onset of symptoms were prospectively documented and analyzed for the occurrence of early severe acute pancreatitis (ESAP). ESAP was defined as presence of organ failure (OF) at admission. Forty-seven (30%) patients had ESAP, compared with 111 patients without OF (SAP group). In a multivariate analysis, the main factor predisposing to ESAP was the presence of extended pancreatic necrosis (odds ratio, 3.8), whereas biliary pancreatitis was associated with a slightly lower risk compared with alcoholic pancreatitis (odds ratio, 0.34). Compared with SAP, patients with ESAP more frequently developed intractable organ failure, which posed the indication for surgical treatment. Surgical necrosectomy due to progressive OF had to be performed in 89% of the ESAP patients and in 60% of the SAP patients. The incidence of infected pancreatic necrosis did not differ between both groups (23 vs. 21%). Mortality was significantly higher in ESAP (42 vs. 14%;p = 0.0003). ESAP is characterized by the presence of extended pancreatic necrosis and a complicated clinical course. Intractable organ failure is a frequent finding. Given the poor prognosis of ESAP, these patients should be treated in specialized intensive care units.

Pathophysiologic role of oxygen free radicals in acute pancreatitis: initiating event or mediator of tissue damage?

BACKGROUND AND OBJECTIVE Oxidative stress is an important factor in the pathogenesis of acute pancreatitis, as shown in vivo by the beneficial effects of scavenger treatment and in vitro by the potential of free radicals to induce acinar cell damage. However, it is still unclear whether oxygen free radicals (OFR) act only as mediators of tissue damage or represent the initiating event in acute pancreatitis in vivo as well. In the present study the authors aimed to address this issue in an experimental set-up. MATERIALS AND METHODS Two hundred male Wistar rats were randomly assigned to one of the following experimental groups. In two groups, acute necrotizing pancreatitis was induced by retrograde intraductal infusion of 3% sodium taurocholate. Through the abdominal aorta, a catheter was advanced to the origin of the celiac artery for continuous regional arterial (CRA) pretreatment with isotonic saline (NP-S group) or superoxide dismutase/catalase (NP-SOD/CAT group). In another group, oxidative stress was generated by CRA administration of xanthine oxidase and intravenous administration of hypoxanthine (HX/XOD group). Sham-operated rats received isotonic saline both arterially and intraductally. After observation periods of 5 and 30 minutes and 3 and 6 hours, the pancreas was removed for light microscopy and determination of reduced glutathione (GSH), oxidized glutathione (GSSG), conjugated dienes (CD), and malondialdehyde as a marker for OFR-induced lipid peroxidation as well as myeloperoxidase as a parameter for polymorphonuclear leukocyte accumulation. RESULTS A significant decrease of GSH was paralleled by an increased ratio of GSSG per total glutathione and elevated CD levels after 5 minutes in the NP-S group versus the sham-operated group. Thereafter, the percentage of GSSG and GSH returned to normal levels until the 6-hour time point. After a temporary decrease after 30 minutes, CD levels increased again at 3 hours and were significantly higher at 6 hours in contrast to sham-operated rats. Myeloperoxidase levels were significantly elevated at 3 and 6 hours after pancreatitis induction. In contrast to NP-S rats, treatment with SOD/CAT significantly attenuated the changes in glutathione metabolism within the first 30 minutes and the increase of CDs after 6 hours. HX/XOD administration lead to changes in levels of GSH, GSSG, and CDs at 5 minutes as well as to increased myeloperoxidase levels at 3 hours; these changes were similar to those observed in NP-S rats. Acinar cell damage including necrosis was present after 5 minutes in both NP groups, but did not develop in HX/XOD rats. In addition, serum amylase and lipase levels did not increase in the latter group. SOD/CAT treatment significantly attenuated acinar cell damage and inflammatory infiltrate compared with NP-S animals during the later time intervals. CONCLUSION OFRs are important mediators of tissue damage. However, extracellular OFR generation alone does not induce the typical enzymatic and morphologic changes of acute pancreatitis. Factors other than OFRs must be involved for triggering acute pancreatitis in vivo.

Genomic DNA-Chip Hybridization Reveals a Higher Incidence of Genomic Amplifications in Pancreatic Cancer than Conventional Comparative Genomic Hybridization and Leads to the Identification of Novel Candidate Genes

Genomic analyses aimed at the detection of high-level DNA amplifications were performed on 13 widely used pancreatic cancer cell lines and 6 pancreatic tumor specimens. For these analyses, array-based comparative genomic hybridization (Matrix-CGH) onto dedicated microarrays was used. In comparison with chromosomal CGH (eight amplifications), a >3-fold number of DNA amplifications was detected (n = 29). The most frequent amplifications mapped to 7p12.3 (three pancreatic cancer cell lines and three pancreatic tumor specimens), 8q24 (four pancreatic cancer cell lines and one pancreatic tumor specimen), 11q13 (three pancreatic cancer cell lines and three pancreatic tumor specimens), and 20q13 (four pancreatic cancer cell lines and three pancreatic tumor specimens). Genes contained in the consensus regions were MYC (8q24), EGFR (7p12.3), and FGF3 (11q13). In six of seven pancreatic cancer cell lines and pancreatic tumor specimens with 20q13 amplifications, the novel candidate gene NFAT C2, which plays a role in the activation of cytokines, was amplified. Other amplifications also affected genes for which a pathogenetic role in pancreatic carcinoma has not been described, such as BCL10 and BCL6, two members of the BCL family. A subset of amplified genes was checked for overexpression by means of real-time PCR, revealing the highest expression levels for BCL6 and BCL10. Thus, Matrix-CGH allows the detection of a high number of amplifications, resulting in the identification of novel candidate genes in pancreatic cancer.

Involvement of chemokine receptor CCR6 in colorectal cancer metastasis.

Various chemokine receptors, namely CXCR4, CCR6 and CCR7, have recently been shown to be involved in the regulation of metastasis in malignant tumors. However, little is known about the role of these receptors in promoting tumor metastasis of colorectal cancer (CRC) to the primary site of CRC metastasis in the liver. To investigate this issue, we analyzed the expression of the chemokine receptors CXCR4, CCR6 and CCR7 in colorectal tumors and colorectal liver metastases. In the present study, 30 human cancer samples from colorectal tissue, 30 human samples from colorectal liver metastases and the adjacent nontumorous liver tissues were screened using quantitative real-time PCR, Western blot analysis, histochemistry, microdissection and the enzyme-linked immunosorbent assay (ELISA). While an overexpression of all the chemokine receptors was found in CRC, in colorectal liver metastases only the chemokine receptors CXCR4 and CCR6 were significantly upregulated. Consequently, we investigated the expression of the corresponding ligands CXCL12/SDF1α, CCL20/MIP3α, CCL19/MIP3β and CCL21/6Ckine in various organs, such as the stomach, esophagus, pancreas, colon and rectum, in comparison with their expression in the liver as the primary site of metastatic spread in CRC. We found that only CCL20 exhibits peak levels of expression in the liver, thus indicating that an increased production of CCL20 may contribute to the selective recruitment of CCR6-expressing cancer cells in CRC. Furthermore, we could demonstrate that CRC patients who developed liver metastases express significantly more CCL20 and CCL21 in the liver in comparison with an unaffected control group. Therefore, our findings strongly suggest an association between CCL20/CCR6 expression in human CRC and the promotion of colorectal liver metastasis.

Serum amyloid A versus C-reactive protein in acute pancreatitis: clinical value of an alternative acute-phase reactant.

Objectives: The acute‐phase reactant C‐reactive protein (CRP) is currently the serum variable of choice for an early, accurate, and cost‐effective severity assessment of acute pancreatitis in the daily clinical routine. Serum amyloid A (SAA) proteins comprise a family of apolipoproteins that constitute another major acute‐phase reactant and thus could be a potential alternative to CRP assessment. In the present study we investigated the clinical usefulness of SAA determinations in acute pancreatitis using an automated immunoassay technique. Design: Cohort study, comparing patients with complicated and mild acute pancreatitis; control groups included individuals with further abdominal disorders and healthy volunteers. Setting: A collaborative study between the department of general surgery and the routine laboratory of the department of clinical chemistry/pathobiochemistry. Patients: We enrolled 66 patients with acute pancreatitis in the present study. Control groups consisted of healthy subjects (n = 30), patients with chronic pancreatitis (n = 20), patients with pancreatic carcinoma (n = 20), and patients with acute appendicitis (n = 20). Interventions: Blood samples were collected during 14 consecutive days in patients with acute pancreatitis. A single blood specimen was taken in all control groups after the diagnosis was established. Measurements and Main Results: SAA concentrations were 3 mg/L (median; range, 3‐93) in healthy subjects. Although SAA and CRP both reached their maximum within 4 days after onset of symptoms in patients with acute pancreatitis, SAA concentrations rose faster above normal ranges and reached 676 mg/L (median; range, 12‐1880), higher than CRP, which reached 313 mg/L (median; range, 29‐613). As observed for CRP, SAA was significantly higher in patients who developed complications such as necrosis, infection of necrosis, or multiple organ dysfunction syndrome or in patients who died. SAA achieved best results in discriminating between necrotizing pancreatitis and interstitial edematous pancreatitis. However, CRP provided an earlier differentiation between both entities and a significantly better overall accuracy, as shown by receiver operating characteristics analysis. SAA concentrations in patients with chronic pancreatitis were 6 mg/L (median; range, 3‐756). In patients with pancreatic carcinoma, SAA concentrations were 7 mg/L (median; range, 3‐492), and in patients with acute appendicitis, they were 50 mg/L (median; range, 3‐2140). Conclusion: SAA is a nonspecific and rapidly produced variable in inflammatory abdominal disorders with a wider dynamic range than CRP. The current assay technique renders SAA an applicable and readily available variable under clinical routine conditions. In cases of acute pancreatitis, however, CRP is still superior to SAA for early and accurate stratification of patients with a complicated course.

Therapeutic Application of Caspase 1/Interleukin-1β-Converting Enzyme Inhibitor Decreases the Death Rate in Severe Acute Experimental Pancreatitis

ObjectiveTo assess the effect of therapeutic inhibition of interleukin 1&bgr;-converting enzyme (ICE) in an experimental model of severe acute pancreatitis (SAP). Summary Background DataSeveral lines of evidence suggest that cytokines activated by ICE play an instrumental role in the course of acute pancreatitis. Recent studies have shown that pharmacologic or genetic blockade of ICE significantly ameliorates the overall severity of and the death rate in SAP. MethodsSevere acute pancreatitis was induced by infusion of 5% sodium taurocholate in Wistar rats. A new, highly selective, irreversible inhibitor of ICE was intraperitoneally applied at a dosage of 0.25 mg every 12 hours. Control animals in group 1 received treatment with saline; in group 2 rats, ICE inhibition was started 6 hours after the onset of pancreatitis; and in group 3 rats, ICE inhibition was started 12 hours after the onset of pancreatitis. After a 7-day observation period, surviving rats were killed and blood, plasma, pancreas, lung, and liver were used for subsequent analysis. ResultsInhibition of ICE decreased the 7-day death rate from 87.5% to 38.9% irrespective whether treatment was started 6 hours or 12 hours after induction of SAP. Morphometric analysis revealed a significant reduction of acinar cell necrosis in both treated groups, whereas pancreatitis-associated pulmonary and hepatic damage was uniformly low and not influenced by ICE inhibition. Tissue myeloperoxidase concentrations were dramatically decreased in the pancreas and the lung after either regimen of ICE inhibitor treatment. In contrast to lung and liver, marked upregulation of interleukin 1&bgr;, tumor necrosis factor &agr;, and ICE mRNA was observed in the pancreas, with levels of interleukin 1&bgr; and tumor necrosis factor &agr; being reduced in ICE-inhibited animals. Compared with nontreated rats, plasma amylase levels were higher in both treatment groups, whereas lipase and hematocrit showed no difference. Changes of the differential white blood count including neutrophils, lymphocytes, and monocytes were attenuated in both groups after ICE inhibitor treatment. ConclusionsPharmacologic inhibition of ICE significantly improves the overall severity of and the death rate in SAP. A substantial reduction of neutrophil-mediated tissue injury in pancreas and lung seems to contribute to the beneficial effects of this approach. Moreover, ICE inhibition is still effective after a therapeutic window of 12 hours. Based on the current findings, future studies on the clinical application of ICE-inhibiting substances in acute pancreatitis seem to be promising.

Clinical relevance of caspase-1 activated cytokines in acute pancreatitis: high correlation of serum interleukin-18 with pancreatic necrosis and systemic complications.

ObjectivesThere is recent experimental evidence that caspase-1 activation plays an instrumental role in the pathomechanism of severe acute pancreatitis. Besides interleukin-1&bgr;, interleukin-18, a recently described proinflammatory cytokine, is cleaved into its biologically active form by caspase-1 as well. Interleukin-18 is known to have potent properties concerning the activation of the Th1-lymphocyte subset via costimulation of interferon-&ggr; production. In contrast to interleukin-1&bgr;, little is known about the clinical impact of interleukin-18 in the course of acute pancreatitis. DesignCohort study comparing patients with mild and severe acute pancreatitis associated with local and systemic complications during the course of the disease. SettingSurgical and anesthesiological intensive care unit as well as wards of the department of general surgery. PatientsWe included 68 patients with acute pancreatitis in the present study. In terms of local complications, pancreatic necrosis was present in 37 patients, of whom 21 developed pancreatic infections. Systemic complications included pulmonary, renal, or cardiocirculatory insufficiency and were observed in 40, 18, and 25 patients, respectively. Severe multiple-organ dysfunction syndrome involving all three organ systems occurred in 18 patients, all suffering from pancreatic necrosis. InterventionsSerum samples were collected over 14 consecutive days after study inclusion. Ascites or peripancreatic exudate was obtained by ultrasound-guided fine needle aspiration in 14 cases. Sera and local aspirates were stored at −70°C until analysis. Measurements and Results Interleukin-18 and interferon-&ggr; were measured by commercially available enzyme-linked immunosorbent assays. Interleukin-18 concentrations were significantly increased after the fourth day of disease onset until the end of the observation period in patients who developed pancreatic necrosis and systemic complications such as pulmonary, renal, and cardiocirculatory failure as well as severe multiple-organ dysfunction syndrome. However, no correlation was found between the development of pancreatic infections and interleukin-18 concentrations. In contrast with interleukin-18, interferon-&ggr; concentrations did not show any significant difference with respect to the presence or absence of either systemic or local complications. Local interleukin-18 concentrations in ascites or peripancreatic exudate were up to 20-fold higher than systemic concentrations, whereas interferon-&ggr; concentrations did not differ. ConclusionsSerum interleukin-18 concentrations are significantly elevated in patients with acute pancreatitis complicated by pancreatic necrosis and remote organ failure. The present data suggest an important role of caspase-1 dependent cytokine activation in the pathomechanism of severe acute pancreatitis beyond the experimental setting. In this context, interleukin-18 may serve as a potential target for new therapeutic approaches.

Procalcitonin: improved biochemical severity stratification and postoperative monitoring in severe abdominal inflammation and sepsis

Background:Infections and sepsis are among the most devastating complications in abdominal surgery and significantly contribute to morbidity and mortality. Early and reliable diagnosis of septic complications is notoriously difficult, and the search for novel approaches to overcome this problem is still a compelling issue for clinicians. Among a large array of inflammatory parameters, procalcitonin (PCT), the 116-amino-acid pro-peptide of calcitonin, has gained considerable importance in identifying patients at risk of developing infection and sepsis in clinical practice.Methods:Along with the latest insights into pathophysiological aspects of this pro-hormone, the literature as well as our own experience on the usefulness of PCT determinations in patients with severe inflammatory abdominal disorders was reviewed.Results:Although the term “sepsis” does not embrace the integral properties of PCT, a remarkable number of clinical studies have demonstrated the pivotal role of this parameter in the host response to microbial and fungal infections. In acute pancreatitis PCT allows early severity stratification and closely correlates with the development of subsequent pancreatic infections. In patients with peritonitis PCT reflects overall disease severity and is an early and reliable indicator of overall prognosis. Postoperative monitoring of PCT is a helpful tool to identify patients with evolving or persisting septic complications after elective and emergency abdominal surgery.Conclusions:Compared with established biochemical routine variables, PCT significantly contributes to earlier and better stratification of patients at risk of developing septic complications and provides excellent prognostic assessment in severe abdominal inflammation. The currently available test systems render PCT an applicable and readily available parameter under clinical routine and emergency conditions.

Modulation of Endogenous Nitric Oxide Synthase in Experimental Acute Pancreatitis: Role of Anti-ICAM-1 and Oxygen Free Radical Scavengers

ObjectiveTo evaluate, in an experimental model of acute pancreatitis, the impact of nitric oxide on the disease process and the interaction between nitric oxide and oxygen free radicals. Summary Background DataNitric oxide and oxygen free radicals are involved in the pathophysiology of acute pancreatitis. It is well established that oxygen free radicals play an important role in the development of pancreatic cell damage and remote organ failure, but the impact of nitric oxide on the disease process and the interactions between the two radical species remain controversial. MethodsNecrotizing pancreatitis (NP) was induced in Wistar rats by intraductal sodium taurocholate infusion after pretreatment with isotonic saline (NP-S), superoxide dismutase/catalase (NP-SOD/CAT), or an anti-ICAM-1 antibody (aICAM-1). Sham-operated rats received isotonic saline (SHX). After an observation period of 5 minutes and 24 hours, the pancreas was removed for microscopy, glutathione, and myeloperoxidase (MPO) analysis. The inducible NO synthase (NOS-2) was detected by Western blotting or RT-PCR. Serum was analyzed for nitrite/nitrate (NO2-/NO3-) and S-nitrosothioles (RSNO), while plasma was used to assay for trypsinogen activation peptides (TAP). ResultsNP-S animals showed a significant decrease in GSH levels after NP-induction as compared with animals under therapy. Increased MPO levels in the NP-S group were significantly reduced by aICAM-1 while SOD/CAT injection showed no changes. Serum NO-derivatives peaked at 12 hours while TAP levels had a maximum at 6 hours after NP induction, and were lower after aICAM-1 application SOD/CAT treatment increased both parameters. Extended acinar cell damage and inflammatory infiltrate developed in NP-S animals and was significantly improved by SOD/CAT and aICAM-1 treatment. RT-PCR and Western-blot analysis revealed NOS-2 expression in the NP-S group, which was reduced by radical scavengers and aICAM-1. ConclusionEnhanced nitric oxide synthase expression and increased nitric oxide derivatives are found during severe acute pancreatitis. Oxygen free radicals and neutrophils seem to be potent and important regulation mechanisms for nitric oxide synthase activity and nitric oxide-mediated toxicity but imply only a secondary role for nitric oxide in the local pathologic mechanism of this disease.