[Updated S2k-Guideline "Complications of liver cirrhosis". German Society of Gastroenterology (DGVS)]

This guideline provides evidence-based key recommendations for diagnosis and therapy of complications of liver cirrhosis and upgrades the 2011 version. An interdisciplinary team of medical experts and patient support groups developed the guideline following the AWMF recommendations for evidence based consensus guidelines. New chapters concerning diagnosis and therapy of hepatic encephalopathy were added.

Polypropylene mesh implantation for hernia repair causes myeloid cell-driven persistent inflammation

Polypropylene meshes that are commonly used for inguinal hernia repair may trigger granulomatous foreign body reactions. Here, we show that asymptomatic patients display mesh-associated inflammatory granulomas long after surgery, which are dominated by monocyte-derived macrophages expressing high levels of inflammatory activation markers. In mice, mesh implantation by the onlay technique induced rapid and strong myeloid cell accumulation, without substantial attenuation for up to 90 days. Myeloid cells segregated into distinct macrophage subsets with separate spatial distribution, activation profiles, and functional properties, showing a stable inflammatory phenotype in the tissue surrounding the biomaterial and a mixed, wound-healing phenotype in the surrounding stromal tissue. Protein mass spectrometry confirmed the inflammatory nature of the foreign body reaction, as characterized by cytokines, complement activation, and matrix-modulating factors. Moreover, immunoglobulin deposition increased over time around the implant, arguing for humoral immune responses in association with the cell-driven inflammation. Intravital multiphoton microscopy revealed a high motility and continuous recruitment of myeloid cells, which is partly dependent on the chemokine receptor CCR2. CCR2-dependent macrophages are particular drivers of fibroblast proliferation. Thus, our work functionally characterizes myeloid cell-dependent inflammation following mesh implantation, thereby providing insights into the dynamics and mechanisms of foreign body reactions to implanted biomaterials.

The risk to develop a recurrence of a gastric cancer-is it independent of time?

BACKGROUND AND AIMS

Recurrence is the main reason for early death of cancer patients. Therefore, survival curves are regarded as crucial tools for clinicians to evaluate therapies and to estimate the patients' prognosis. Current models for the development of recurrence are based on the assumption of a residual cancer cell burden after therapy. Accordingly, in assumption of an exponential cell growth of the cancer cells an S-shaped decline of the survival curve is expected with earlier onset in case of advanced cancer and a later manifestation in case of little residual tumour. However, many survival curves do not reflect any S-shaped configuration and thus may question the current concept.

MATERIALS AND METHODS

To test, whether the incidence for developing a recurrence may be considered as remaining constant over time, we analysed survival data of 446 patients with gastric cancer, operated from 1975-2001 in the Surgical Department of the RWTH Aachen.

RESULTS

All survival curves, even after sub-grouping according to UICC stage, show a monotonous decline without any apparent S-shape. The impact of TNM and UICC stage to predict the survival in patients is estimated by Cox regression, for estimation the risk for death a logistic regression is performed. Whereas the presence of metastasis lowers the prognosis significantly with a hazard ratio of 1.57 and an odds ratio of 7.56, respectively, a significant relevance for the UICC stage, the tumour size or the lymph node status cannot be proven. Furthermore, the two assumptions: (1) that 20% of patients who are still alive after 5 years have been cured, and (2) that the remainder develop a recurrence in constantly 7.3% per month, are able to configure the survival curve almost precisely (correlation coefficient between calculated and observed survival rate r > 0.99).

CONCLUSION

The absence of any S-shaped survival curve configuration is not in accordance with the focus on residual tumour clones with its exponential growth as the decisive process for recurrence development. In contrast, the monotonous decline of surviving patients is best reflected by a constant incidence of recurrence. The (time) constancy of the recurrence incidence encourages the view of recurrent cancer as a chronic problem of a carcinogenic environment. Furthermore, it supports new anticancer therapies which rather targets cell regulation and immunology instead of acting cytotoxic.

Morphology, quality, and composition in mature human peritoneal adhesions

BACKGROUND AND AIM

Peritoneal adhesions are caused by intra-abdominal surgery and can lead to relevant complications. Adhesions are supposed to consist of avascular scar tissue. The aim of the present study was to analyze whether mature postsurgical adhesions even after years still reveal a dynamic remodeling process.

MATERIALS AND METHODS

In a prospective analysis, we investigated tissue specimen of peritoneal adhesions in 40 patients after abdominal surgery. Expression of five parameters representing wound healing and remodeling were examined (MMP-2, Ki-67, apoptosis, collagen/protein ratio, and collagen type I/III ratio).

RESULTS

Gender, age, and the number of previous operations had no impact on the parameters measured. Adhesion specimens were cell rich, containing mononuclear round cells, fibroblasts, adipose cells, and vascular endothelial cells. There was a positive expression of MMP-2 and apoptosis, whereas Ki-67 was marginal irrespective of adhesion maturity or quality. Adhesions classified as dense showed a significant increase in total collagen (118.2 +/- 4.9 microg/mg) and collagen type I/III ratios (3.9 +/- 0.2), whereas there were no significant differences regarding the adhesion maturity.

CONCLUSION

The distinct composition of cellular components as well as of extracellular matrix proteins may reflect an interactive cross-talk between adhesion- and stroma-derived cells even in mature adhesions. Our findings support the hypothesis that the disabilities of appropriate repair of the peritoneal surface leading to persistent adhesions are a consequence of a permanent process of disturbed remodeling.

Different matrix micro-environments in colon cancer and diverticular disease

BACKGROUND AND AIMS

The extracellular matrix and the interactive signalling between its components are thought to play a pivotal role for tumour development and metastasis formation. An altered matrix composition as potential underlying pathology for the development of colorectal cancer was hypothesized.

METHODS

In a retrospective study of patients with colon cancer, the extracellular matrix in tumour-free bowel specimen was investigated in comparison with non-infected bowel specimen from patients operated on for colonic diverticulosis. The following matrix parameters with known associations to tumour formation, cell proliferation, invasion and metastasis were analysed by immunohistochemistry and quantified by a scoring system: VEGF, TGF-beta, ESDN, CD117, c-erb-2, cyclin D1, p53, p27, COX-2, YB-1, collagen I/III, MMP-13, PAI and uPAR. Expression profiles and correlations were calculated.

RESULTS

The comparison of the two groups revealed a significantly decreased immunostaining for CD117 and TGF-beta in the cancer group (8.5+/-2.6 vs 10.3+/-2,1 and 4.9+/-1.5 vs 8.1+/-3, respectively), whereas PAI scores were significantly higher than in patients with diverticular disease (8.1+/-1.6 vs 6.2+/-0.9). Overall correlation patterns of matrix parameters indicated pronounced differences between tumour-free tissue in cancer patients compared with patients with diverticular disease.

CONCLUSIONS

Our results indicate distinct differences in the colonic tissue architecture between cancer patients and patients with diverticulitis that support the notion of an altered matrix composition predisposing to the development of colon cancer.

Biomaterial-dependent MMP-2 expression in fibroblasts from patients with recurrent incisional hernias

With regard to the pathogenesis of recurrent incisional hernia, an impaired connective tissue quality leading to an aberrant scarring process has been proposed. For the matrix metalloproteinase (MMP-2) a pathogenetic involvement in direct inguinal hernia development is reported. With mesh implantation as the gold standard treatment for incisional hernias, the aim of the present study was to investigate the MMP-2 expression in patients with recurrent incisional hernias with and without mesh-materials. In primary fibroblast cultures obtained from skin scars in patients with and without recurrent incisional hernias, MMP-2 synthesis and gene expression were investigated. Furthermore, MMP-2 synthesis and gene expression of fibroblasts were compared after incubation with two different mesh materials: polypropylene and absorbable polyglactin filaments. MMP-2 enzyme activity was determined by semiquantitative zymography and mRNA synthesis by quantitative RT-PCR. Both MMP-2 enzyme activity and mRNA expression were similar in hernia and control fibroblasts in vitro. In control fibroblasts mesh incubation did not significantly affect MMP-2 expression, whereas polypropylene mesh contact of fibroblasts from patients with recurrent incisional hernias led to a major decrease of MMP-2 activity and of mRNA expression. In the absence of biomaterials fibroblasts from recurrent incisional hernia, patients have no alterations of their MMP-2 synthesis compared to control fibroblasts, whereas a specific response was found after biomaterial contact hereby indicating differences in fibroblast phenotype.