Bedeutung von Cysteinyl-Leukotrienen und Prostanoiden in der Pathogenese der portalen Hypertension durch aktivierte Kupfferzellen

Basierend auf den Ergebnissen klinischer Studien müssen bakterielle Infektionen als Trigger akuter Ösophagusvarizenblutungen bei Patienten mit Leberzirrhose angenommen werden. Hierfür werden Permeabilitätsstörungen der Darmwand als Folge der portalen Hypertonie verantwortlich gemacht, die eine Einschwemmung pathogener Darmkeime in die portale Zirkulation begünstigen. Kupffer'sche Sternzellen (KS), die residenten Makrophagen der Leber, kommen nicht nur als größte sondern auch als erste Makrophagenpopulation des menschlichen Körpers mit pathogenen Darmbakterien in Kontakt. Durch bakterielle Bestandteile wie Endotoxine oder die in der Zellwand von Bakterien und Pilzen verankerten β-Glucane, werden KS aktiviert und produzieren in der Folge verschiedene Vasokonstriktoren, die den portalen Druck massiv erhöhen. Die von aktivierten KS gebildeten Vasokonstriktoren sind deshalb als potenzielle Mediatoren einer Infekt- getriggerten Varizenblutung anzusehen. Von großem klinischen Interesse ist deshalb die Identifizierung der verantwortlichen Vasokonstriktoren als Basis für die Entwicklung pharmakologischer Strategien zur Prävention Infekt- getriggerter Varizenblutungen. Bislang konnte die Beteiligung des Cyclooxygenase- Weges und insbesondere die Bildung von Thromboxan A2 (TXA2) an der portalen Druckerhöhung durch aktivierte KS nachgewiesen werden. Allerdings konnte im Tierexperiment durch den Einsatz von Cyclooxygenase- Inhibitoren und TXA2 -Antagonisten der portale Druckanstieg nach KS Aktivierung nur um 50% reduziert werden, weshalb die Beteiligung weiterer Vasokonstriktoren angenommen werden muss. Die Identifizierung der bislang unbekannten Vasokonstriktoren als wesentliches Ziel der vorliegenden Arbeit erscheint nicht zuletzt auch deshalb von besonderem klinischen Interesse, da sich eine pharmakologische Hemmung der bislang identifizierten Cyclooxygenase- bzw. TXA2- abhängigen Wege der Vasokonstriktion bei Patienten mit Leberzirrhose wegen der Gefahr schwerwiegender Nebenwirkungen verbietet. In der vorliegenden Arbeit sollte deshalb die Rolle vasokonstriktorischer Cysteinyl-Leukotriene (Cys-LT) bei der portalen Druckerhöhung durch aktivierte KS untersucht werden. Die Experimente wurden am Modell der isoliert perfundierten Rattenleber durchgeführt. Zusammenfassend führen die Ergebnisse zu einem neuen Konzept der portalen Hypertension durch β-Glucane unter Beteiligung aktivierter KS, TXA2 und Cys-LT. Ferner zeigen diese Ergebnisse erstmals eine bislang nicht beschriebene Vernetzung von Prostaglandin- und Cys-LT- Signalwegen unter der Kontrolle von TXA2- und Cys-LT1-Rezeptoren. Für die portale Druckerhöhung nach KS-Aktivierung muss ein durch TXA2 mediierter Mechanismus der Cys-LT –Bildung mit nachfolgender CysLT1–Rezeptorstimulation angenommen werden. 5-Lipoxygenase- Inhibitoren wie MK 886, die die Synthese von Prostanoiden nicht beeinflussen, sind dabei als besonders aussichtsreiche Kandidaten zur pharmakologischen Prävention der Infekt- getriggerten portalen Hypertension zu erachten

Bedeutung von Cysteinyl-Leukotrienen und Prostanoiden in der Pathogenese der portalen Hypertension durch aktivierte Kupfferzellen

Basierend auf den Ergebnissen klinischer Studien müssen bakterielle Infektionen als Trigger akuter Ösophagusvarizenblutungen bei Patienten mit Leberzirrhose angenommen werden. Hierfür werden Permeabilitätsstörungen der Darmwand als Folge der portalen Hypertonie verantwortlich gemacht, die eine Einschwemmung pathogener Darmkeime in die portale Zirkulation begünstigen. Kupffer'sche Sternzellen (KS), die residenten Makrophagen der Leber, kommen nicht nur als größte sondern auch als erste Makrophagenpopulation des menschlichen Körpers mit pathogenen Darmbakterien in Kontakt. Durch bakterielle Bestandteile wie Endotoxine oder die in der Zellwand von Bakterien und Pilzen verankerten β-Glucane, werden KS aktiviert und produzieren in der Folge verschiedene Vasokonstriktoren, die den portalen Druck massiv erhöhen. Die von aktivierten KS gebildeten Vasokonstriktoren sind deshalb als potenzielle Mediatoren einer Infekt- getriggerten Varizenblutung anzusehen. Von großem klinischen Interesse ist deshalb die Identifizierung der verantwortlichen Vasokonstriktoren als Basis für die Entwicklung pharmakologischer Strategien zur Prävention Infekt- getriggerter Varizenblutungen. Bislang konnte die Beteiligung des Cyclooxygenase- Weges und insbesondere die Bildung von Thromboxan A2 (TXA2) an der portalen Druckerhöhung durch aktivierte KS nachgewiesen werden. Allerdings konnte im Tierexperiment durch den Einsatz von Cyclooxygenase- Inhibitoren und TXA2 -Antagonisten der portale Druckanstieg nach KS Aktivierung nur um 50% reduziert werden, weshalb die Beteiligung weiterer Vasokonstriktoren angenommen werden muss. Die Identifizierung der bislang unbekannten Vasokonstriktoren als wesentliches Ziel der vorliegenden Arbeit erscheint nicht zuletzt auch deshalb von besonderem klinischen Interesse, da sich eine pharmakologische Hemmung der bislang identifizierten Cyclooxygenase- bzw. TXA2- abhängigen Wege der Vasokonstriktion bei Patienten mit Leberzirrhose wegen der Gefahr schwerwiegender Nebenwirkungen verbietet. In der vorliegenden Arbeit sollte deshalb die Rolle vasokonstriktorischer Cysteinyl-Leukotriene (Cys-LT) bei der portalen Druckerhöhung durch aktivierte KS untersucht werden. Die Experimente wurden am Modell der isoliert perfundierten Rattenleber durchgeführt. Zusammenfassend führen die Ergebnisse zu einem neuen Konzept der portalen Hypertension durch β-Glucane unter Beteiligung aktivierter KS, TXA2 und Cys-LT. Ferner zeigen diese Ergebnisse erstmals eine bislang nicht beschriebene Vernetzung von Prostaglandin- und Cys-LT- Signalwegen unter der Kontrolle von TXA2- und Cys-LT1-Rezeptoren. Für die portale Druckerhöhung nach KS-Aktivierung muss ein durch TXA2 mediierter Mechanismus der Cys-LT –Bildung mit nachfolgender CysLT1–Rezeptorstimulation angenommen werden. 5-Lipoxygenase- Inhibitoren wie MK 886, die die Synthese von Prostanoiden nicht beeinflussen, sind dabei als besonders aussichtsreiche Kandidaten zur pharmakologischen Prävention der Infekt- getriggerten portalen Hypertension zu erachten

Prognosis of patients with hepatocellular carcinoma. Validation and ranking of established staging-systems in a large western HCC-cohort.

HCC is diagnosed in approximately half a million people per year, worldwide. Staging is a more complex issue than in most other cancer entities and, mainly due to unique geographic characteristics of the disease, no universally accepted staging system exists to date. Focusing on survival rates we analyzed demographic, etiological, clinical, laboratory and tumor characteristics of HCC-patients in our institution and applied the common staging systems. Furthermore we aimed at identifying the most suitable of the current staging systems for predicting survival. Overall, 405 patients with HCC were identified from an electronic medical record database. The following seven staging systems were applied and ranked according to their ability to predict survival by using the Akaike information criterion (AIC) and the concordance-index (c-index): BCLC, CLIP, GETCH, JIS, Okuda, TNM and Child-Pugh. Separately, every single variable of each staging system was tested for prognostic meaning in uni- and multivariate analysis. Alcoholic cirrhosis (44.4%) was the leading etiological factor followed by viral hepatitis C (18.8%). Median survival was 18.1 months (95%-CI: 15.2-22.2). Ascites, bilirubin, alkaline phosphatase, AFP, number of tumor nodes and the BCLC tumor extension remained independent prognostic factors in multivariate analysis. Overall, all of the tested staging systems showed a reasonable discriminatory ability. CLIP (closely followed by JIS) was the top-ranked score in terms of prognostic capability with the best values of the AIC and c-index (AIC 2286, c-index 0.71), surpassing other established staging systems like BCLC (AIC 2343, c-index 0.66). The unidimensional scores TNM (AIC 2342, c-index 0.64) and Child-Pugh (AIC 2369, c-index 0.63) performed in an inferior fashion. Compared with six other staging systems, the CLIP-score was identified as the most suitable staging system for predicting prognosis in a large German cohort of predominantly non-surgical HCC-patients

A Direct Comparison of the Prevalence of Advanced Adenoma and Cancer between Surveillance and Screening Colonoscopies

Background/Aims: Surveillance colonoscopy is recommended afterpolypectomy of adenoma and surgery for colorectal cancer. The purpose ofthis study was to assess the frequency of advanced adenoma and cancer incolonoscopies performed for surveillance compared to screeningcolonoscopies. Methods: Analysis of relative frequencies of findings incolonoscopies performed for post-adenoma surveillance (post-ad),post-cancer surveillance (post-crc), screening, and follow-up of apositive fecal occult blood test (FOBT). Logistic regression was used toidentify the risk for advanced adenoma (adenoma mm, containinghigh-grade dysplasia, or villous histology) and cancer. Results: 324,912 colonoscopies were included in the analysis: 81,877 post-ad, 26,89 6post-crc, 178,305 screening, 37,834 positive FOBT. Advanced adenoma(cancer) was diagnosed in 8.0% (0.4%) of post-ad, 5.0% (1.0%) ofpost-crc, 7.4% (1.1%) of screening, and 11.7% (3.6%) of positiveFOBT colonoscopies. Compared to screening, the odds ratios for findingadvanced adenoma were 0.93 (95% CI 0.88-0.98) for post-ad, 0.96(0.86-1.08) for post-crc, and 1.18 (1.09-1.28) for positive FOBTcolonoscopies. The odds ratios for the diagnosis of cancer were 0.29(0.24-0.36) for post-ad, 0.81 (0.61-1.07) for post-crc, and 2.77(2.43-3.17) for positive FOBT. Conclusion: Colonoscopy for post-adsurveillance but not colonoscopy for post-crc surveillance is associatedwith a lower risk of diagnosis of advanced adenoma and cancer

Transarterial chemoembolization for hepatocellular carcinoma: development and external validation of the Munich-TACE score

Background: Allocation of patients with hepatocellular carcinoma (HCC) to the adequate therapy is determined by both tumor burden and liver function. The Barcelona Clinic Liver Cancer (BCLC) staging system and therapeutic algorithm recommends transarterial chemoembolization (TACE) based on the best evidence available to patients with intermediate-stage HCC (BCLC-B). However, many centers also treat subgroups of patients outside these recommendations and with more advanced disease by TACE. The purpose of this study was to identify prognostic factors in a TACE cohort, including BCLC-B patients, as well as patients treated outside of BCLC-B, to test the prognostic capabilities of published staging systems and to optimize prognostication for TACE patients.Patients and Methods: A cohort of 186 first-line TACE patients was analyzed. Independent prognostic factors were identified and used to construct the Munich-TACE score (M-TACE). M-TACE was tested against established staging systems (including BCLC and two recently published TACE-specific scores) and a ranking using concordance index and Akaike Information Criterion was performed. Finally, an external validation in an independent TACE cohort (n=71) was conducted.Results: Bilirubin, Quick/international normalized ratio, C-reactive protein, creatinine, -feto protein, and tumor extension were identified as independent prognostic factors and used to construct M-TACE. M-TACE identifies three distinct subgroups (P<0.0001) with median survival times of 35.2, 16.9, and 8.6 months, respectively. Compared with established staging systems, M-TACE showed the best prognostic capabilities in both cohorts of patients (cohort 1: c-index, 0.71;Akaike Information Criterion: 1276;cohort 2: c-index, 0.754).Conclusion: We identified independent risk factors for patients treated with TACE. The newly constructed M-TACE score is superior to established staging systems and might prove helpful to identify patients who are most suitable for TACE

A Direct Comparison of the Prevalence of Advanced Adenoma and Cancer between Surveillance and Screening Colonoscopies

Background/Aims: Surveillance colonoscopy is recommended afterpolypectomy of adenoma and surgery for colorectal cancer. The purpose ofthis study was to assess the frequency of advanced adenoma and cancer incolonoscopies performed for surveillance compared to screeningcolonoscopies. Methods: Analysis of relative frequencies of findings incolonoscopies performed for post-adenoma surveillance (post-ad),post-cancer surveillance (post-crc), screening, and follow-up of apositive fecal occult blood test (FOBT). Logistic regression was used toidentify the risk for advanced adenoma (adenoma mm, containinghigh-grade dysplasia, or villous histology) and cancer. Results: 324,912 colonoscopies were included in the analysis: 81,877 post-ad, 26,89 6post-crc, 178,305 screening, 37,834 positive FOBT. Advanced adenoma(cancer) was diagnosed in 8.0% (0.4%) of post-ad, 5.0% (1.0%) ofpost-crc, 7.4% (1.1%) of screening, and 11.7% (3.6%) of positiveFOBT colonoscopies. Compared to screening, the odds ratios for findingadvanced adenoma were 0.93 (95% CI 0.88-0.98) for post-ad, 0.96(0.86-1.08) for post-crc, and 1.18 (1.09-1.28) for positive FOBTcolonoscopies. The odds ratios for the diagnosis of cancer were 0.29(0.24-0.36) for post-ad, 0.81 (0.61-1.07) for post-crc, and 2.77(2.43-3.17) for positive FOBT. Conclusion: Colonoscopy for post-adsurveillance but not colonoscopy for post-crc surveillance is associatedwith a lower risk of diagnosis of advanced adenoma and cancer

Differential significance of early surgical complications for acute and long-term recurrence-free survival following surgical resection of hepatocellular carcinoma: do comorbidities play a role?

Background Postoperative complications of Clavien-Dindo grade 3 or more are of prognostic significance in patients who undergo liver resection for hepatocellular carcinoma (HCC). However, perioperative mortality and patient comorbidities represent relevant factors that interfere with postoperative long-term survival. To clarify this, a retrospective single-center study was carried out. Patients and methods Patient data were prospectively collected in a continuously updated liver resection database. Overall, 184 consecutive patients who underwent liver resection for HCC with a curative intent between March 2003 and December 2013 were selected for the study. The patients were assigned to two groups according to the presence or absence of postoperative complications. Pre-existing comorbidities, perioperative mortality, surgical outcome, and long-term survival data were analyzed. Results Postoperative complications requiring revision surgery were identified in 17.4% of the patients. The in-house mortality rate was 4.8%. Compared with patients without complications, patients with complications were older and had significantly more pre-existing comorbidities, more advanced tumors, more intrahepatic metastasis, longer operation times, greater blood loss, and more extensive resections. The overall 5-year survival rates were 40.1 and 52.5% in patients with or without postoperative complications, respectively. The corresponding 5-year recurrence-free survival rates were 46.3 and 46.7% (perioperative mortality excluded). Multivariate analysis showed that elevation of the Charlson Comorbidity Index was associated independently with decreased overall and recurrence-free survival. Conclusion In patients with HCC, posthepatectomy complications are confirmed to have predictive value. However, closer analysis and exclusion of perioperative mortality effects show an independent impact of pre-existing comorbidities on long-term overall und recurrence-free survival

Miliary pattern of brain metastases - a case report of a hyperacute onset in a patient with malignant melanoma documented by magnetic resonance imaging

Background Miliary brain metastases are a rare condition but associated with an exceedingly poor prognosis. We present the case of a patient suffering from malignant melanoma with an acute progressively worsening of neurological symptoms up to the loss of consciousness. The magnetic resonance imaging (MRI) demonstrated a new onset of disseminated, miliary spread of central nervous system metastases from a malignant melanoma within 4 days. Case presentation We report on a 57-year-old woman suffering from metastatic malignant melanoma positive for BRAF-V600E mutation who developed an acute onset of neurological symptoms. The patient received vemurafenib and dacarbacin as chemotherapeutic regime for treatment of malignant melanoma. After admission to our hospital due to progressive disturbance of memory and speech difficulty a magnetic resonance tomography (MRI) was performed. This showed no evidence of cerebral tumour manifestation. The symptoms progressed until a loss of consciousness occurred on day five after admission and the patient was admitted to our intensive care unit for orotracheal intubation. No evidence for infectious, metabolic or autoimmune cerebral disorders was found. Due to the inexplicable acute worsening of the neurological symptoms a second MRI was performed on day five. This revealed a new onset of innumerable contrast-enhancing miliary lesions, especially in the grey matter which was proven as metastases from malignant melanoma on histopathology. Conclusion This case describes an unique hyperacute onset of tumour progression correlating with an acute deterioration of neurological symptoms in a patient suffering from miliary brain metastasis from BRAF positive malignant melanoma

Addition of local hepatic therapy to sorafenib in patients with advanced hepatocellular carcinoma (stage BCLC C)

BACKGROUND/AIMS For most patients with hepatocellular carcinoma (HCC), diagnosis is invariably done only in the advanced stages of the disease. For advanced, non-metastatic stage, standard therapy is transarterial chemoembolization (TACE). For metastatic disease, the recommended therapy is systemic treatment with sorafenib. In this study, we evaluated the benefit of an additional local hepatic treatment for patients with advanced metastatic disease. METHODS In a retrospective study, we assessed the overall survival (OS), time to progression (TTP), and disease control rate (DCR) in 37 patients with metastasized HCC treated with sorafenib. Sixteen patients received additional local therapy, while 21 patients received only sorafenib. RESULTS Median OS of patients with combined therapy was significantly higher with 25 months (95% CI: 13.7-36.3 months) as compared to 11 months (95% CI: 6.2-15.8 months) in patients treated with sorafenib alone. TTP was 7 months (95% CI: 5.3-8.7 months) compared to 5 months (95% CI: 3-7 months) and DCR was 87 versus 72% after 3 months and 31 versus 22% after 9 months. CONCLUSION These data suggest that control of the liver tumor burden by local therapy in combination with sorafenib might prove beneficial for metastasized HCC. Randomised studies are needed to confirm this exploratory finding