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Background & Aims: This study was performed to improve the autofluorescence imaging (AFI) in the upper GI tract by applying a new method of normalized autofluorescence (NAFI) obtained via tri-modal imaging., Objective: NAFI may provide lower false positive rate to achieve ultimately better specificity at acceptable sensitivity., Patients and Methods: This is a prospective, controlled single-centre study. 18 patients with suspected esophagus or stomach cancer undergoing esophagogastroduodenoscopy (EGD) were enrolled between February and May 2010. After endoscopy each patient was assigned into one of two groups: (1) non-cancer, including inflammation; (2) cancer group. EGDs were performed using video white light endoscopy, followed by AFI/NAFI. The targeted biopsy samples were taken from the abnormal areas as well as from adjacent mucosa. NAFI was compared versus AFI for cancer diagnostics in terms of specificity and sensitivity., Results: NAFI detected all neoplastic lesions. WLE or NBI detected no additional neoplasia. The AFI displayed mucosal inflammation and carcinomas of esophagus and stomach as dark red color, the normal mucosa background was displayed as light green. The NAFI didn't differentiate inflamed tissue from normal in majority of cases, but in tumorous mucosa, the cancer areas were detected precisely. AFI shows 100% sensitivity but 50% specificity which correlates with previous literature data. On the other hand, NAFI demonstrated lower sensitivity (88%) but higher specificity compared to AFI (69%)., Conclusions: Measuring the NAFI instead of the AFI was found improving the specificity of cancer diagnosis. Use of fiber-optic endoscopes to analyze AFI and possible endoscopic and histological sampling error are the main potential limitations of this method.

Background: The aim of this retrospective study was to evaluate the efficacy and safety of weekly high-dose 5-fluorouracil (5-FU)/folinic acid (FA) as 24-h infusion (AIO regimen) plus irinotecan in patients with histologically proven metastatic gastroesophageal adenocarcinoma (UICC stage IV)., Material/methods: From 08/1999 to 12/2008, 76 registered, previously untreated patients were evaluable. Treatment regimen: irinotecan (80 mg/m²) as 1-h infusion followed by 5-FU (2000 mg/m²) combined with FA (500 mg/m²) as 24-h infusion (d1, 8, 15, 22, 29, 36, qd 57)., Results: Median age: 59 years; male/female: 74%/26%; ECOG ≤1: 83%; response: CR: 1%, PR: 16%, SD: 61%, PD: 17%, not evaluable in terms of response: 5%; tumor control: 78%; median OS: 11.2 months; median time-to-progression: 5.3 months; 1-year survival rate: 49%; 2-year survival rate: 17%; no evidence of disease: 6.6%; higher grade toxicities (grade 3/4): anemia: 7%, leucopenia: 1%, ascites: 3%, nausea: 3%, infections: 12%, vomiting: 9%, GI bleeding of the primary tumor: 4%, diarrhea: 17%, thromboembolic events: 4%; secondary metastatic resection after downsizing: 16 patients (21%), R-classification of secondary resections: R0/R1/R2: 81%/6%/13%, median survival of the 16 patients with secondary resection: 23.7 months., Conclusions: Combined 5-FU/FA as 24-h infusion plus irinotecan may be considered as an active palliative first-line treatment accompanied by tolerable toxicity; thus offering an alternative to cisplatin-based treatment regimens. Thanks to efficient interdisciplinary teamwork, secondary metastatic resections could be performed in 16 patients. In total, the patients who had undergone secondary resection had a median survival of 23.7 months, whereas the median survival of patients without secondary resection was 10.1 months (p≤0.001).

Objective: The growth behaviour of well-differentiated neuroendocrine carcinomas of the gastro-entero-pancreatic system varies greatly and parameters predicting their prognosis are lacking. The aim of our study was to investigate whether tumour growth could be correlated with the release of proangiogenic factors into the circulation., Patients and Methods: Circulating vascular endothelial growth factor (VEGF), interleukin-8 (IL-8), basic fibroblast growth factor (bFGF) and angiogenin were measured in 38 patients with advanced neuroendocrine carcinomas and compared to healthy age-matched controls. In 20 patients, angiogenic cytokine levels were measured at consecutive time points and correlated to tumour progression as assessed by abdominal CT scan, MRI and chromogranin A levels., Results: VEGF levels were elevated in patients compared to controls (P < 0.002) and clearly associated with tumour progression (P < 0.005). Angiogenin levels were significantly higher in patients than in controls (P < 0.003), while high IL-8 levels were predictive of shorter survival. Angiogenin and bFGF levels were correlated neither with tumour growth nor with patient survival., Conclusions: VEGF and IL-8 are associated with tumour progression and might qualify as markers of prognosis and therapy control in patients with neuroendocrine carcinomas. Our results support the notion that specific anti-angiogenic therapies should be evaluated in neuroendocrine carcinoma patients.

Peroxisome proliferator-activated receptor gamma (PPARgamma) is a ligand-dependent transcription factor involved in various processes including the inflammation and carcinogenesis. The aim of the present study was 1) to examine the mRNA and protein expression of PPARgamma in gastric cancer (GC); 2) to evaluate the effect of PPARgamma ligand (ciglitazone) on the proliferation and apoptosis of GC cell line; and 3) to assess the levels of gastric tissue proinflammatory cytokines, IL-1beta and IL-8, and plasma gastrin in GC patients before and after Helicobacter pylori (H. pylori) eradication. The trial material included 30 H. pylori-negative controls and 30 sex- and age-matched GC patients without or with H. pylori before and after its eradication. Expression of tissue PPARgamma, tissue levels of IL-1beta and IL-8, and plasma concentration of gastrin were significantly higher in H. pylori-positive GC compared to controls, but H. pylori eradication significantly reduced these parameters. Kato III cells incubated with alive H. pylori upregulated PPARgamma expression and ciglitazone inhibited cell proliferation and induced apoptosis. PPARgamma, proinflammatory cytokines and plasma gastrin appear to be implicated in H. pylori-related gastric carcinogenesis and PPARgamma agonists may have potential in cancer therapy.

Background: The aim of this study was to evaluate light-induced autofluorescence spectroscopy for the in vivo diagnosis of gastric cancer., Methods: A total of 344 endogenous fluorescence spectra were obtained from normal (164) and cancerous gastric mucosa (180) in 15 patients with pure adenocarcinoma and in 16 patients with gastric cancer containing signet-ring cells. A special light source capable of delivering either white or violet-blue light for the excitation of tissue autofluorescence via the endoscope was used. Endogenous fluorescence spectra emitted by the tissue were collected with a fiberoptic probe and analyzed with a spectrograph., Results: Gastric adenocarcinoma exhibits specific changes in the emitted fluorescence spectra as compared with normal gastric mucosa. By algorithmic classification of the spectra, a sensitivity of 84%, specificity of 87%, a likelihood ratio for a positive test of 6.5 and for a negative test of 0.18 were obtained for the diagnosis of pure adenocarcinoma of the stomach. However, gastric cancer with signet-ring cells exhibits great variation in emitted autofluorescence spectra as compared with normal mucosa. The sensitivity for the diagnosis of all carcinomas containing signet-ring cells was 55%, specificity 85%, the likelihood ratio for a positive test was 3.7 and for a negative test, 0.53. The diagnostic value decreases with increasing numbers of signet-ring cells and tumor grade., Conclusions: Light-induced autofluorescence spectroscopy is a new and promising bio-optical technique for the endoscopic in vivo diagnosis of gastric adenocarcinoma. The poor diagnostic accuracy for signet-ring cell carcinoma may be explained by the diffuse and frequent submucosal growth of this tumor and the presence of collagen fibers.

Cyclooxygenase-2 (COX-2) expression and certain growth hormones, such as gastrin, have been related to gastric carcinogenesis, but little is known about the factors that enhance this COX-2 expression and whether specific blockade of this enzyme has any influence on tumor growth and progression. Our objective was to determine the influence of a specific COX-2 inhibitor, rofecoxib (Vioxx), on serum and tumor levels of gastrin and its precursor, progastrin, as well as on tumor gene expression of COX-2, peroxisome proliferator-activated receptor gamma (PPARgamma), and apoptosis-related proteins (Bax and Bcl-2, caspase-3, and survivin). Twenty-four gastric cancer (GC) patients entered this study and were examined twice, once before and then following a 14-day treatment with Vioxx at a dose of 25 mg twice daily. For comparison, 48 age- and sex-matched healthy controls and 24 similarly matched Helicobacter pylori (Hp)-positive subjects were enrolled and treated with Vioxx as GC patients. Serum levels of anti-Hp and anti-CagA antibodies as well as IL-8 and TNF-alpha were measured by enzyme-linked immunosorbent assay (ELISA), while serum and tumor contents of progastrin and amidated gastrin were determined by specific RIA. Tumor gene and protein expressions of COX-2, PPARgamma, Bax and Bcl-2, caspase-3, and survivin were determined by RT-PCR and western blot. The overall Hp and CagA seropositivity in 24 GC patients was significantly higher (82% and 47%) than in 48 controls (61% and 22%) but not in 24 Hp-infected subjects (100% and 38%). Serum IL-8 and TNF-alpha values were significantly higher in GC patients than in controls without GC or Hp-infected controls. Median serum progastrin and gastrin levels were found to be significantly higher in GC than in controls without GC and in Hp-positive subjects. Treatment of GC patients with Vioxx resulted in a significant decrease in plasma and tumor contents of both progastrin and gastrin, and this was accompanied by the increment in tumor expression of COX-2, PPARy, Bax, and caspase-3 with a concomitant reduction in Bcl-2 and survivin expression. We conclude that: (1) GC patients show significantly higher Hp and CagA seropositivity than age- and sex-matched controls, but not Hp-positive subjects, indicating that infection with cytotoxic Hp is linked to GC. (2) Serum progastrin and gastrin levels are significantly higher in GC patients than in matched controls, confirming that both gastrins may be implicated in gastric carcinogenesis. (3) GC patients exhibit significantly higher levels of IL-8 and TNF-alpha than non-GC controls and Hp-positive subjects, probably reflecting more widespread gastritis in GC. (4) COX-2, PPARgamma, Bcl-2, and survivin were overexpressed in gastric tumor, but the inhibition of COX-2 activity by Vioxx resulted in a significant reduction in serum and tumor levels of progastrin and gastrin and serum IL-8 and TNF-alpha levels, suggesting that gastrin and proinflammatory cytokines could mediate the up-regulation of COX-2 in gastric cancerogenesis. (5) Vioxx also enhanced expression of COX-2, PPARy, Bax, and caspase-3, while inhibiting the expression of Bcl-2 and survivin, suggesting that COX-2 blockade might be useful in chemoprevention against gastric cancer possibly due to enhancement of the PPARy- and proapoptotic proteins-dependent apoptosis and the reduction in progastrin/gastrin-induced promotion of tumor growth.

Background: Helicobacter pylori (Hp) infection represents a crucial factor in pathogenesis of gastric cancer (GC). Factors emanating from bacterium as well as from environmental contributions such as salt diet and inadequate supply of antioxidants, affect the risk for GC development., Results: Atrophic gastritis is considered to be a precursor lesion of intestinal type GC that is accompanied by hypergastrinemia with subsequent induction of cyclooxygenase-2 (COX-2), whose products are responsible for slowing apoptosis and for angiogenesis in GC tumor. The involvement of proinflammatory cytokines (especially IL-1 and IL-8) and reactive oxygen species (ROS) due to NF kappa B activation, increased cell proliferation combined with inhibition of apoptosis as well as upregulation of peroxisome proliferation activated receptor gamma (PPAR gamma) and inducible nitric oxide synthase (iNOS) appear to be major molecular biology alterations in pathogenesis of GC., Conclusions: These results suggest the therapeutic usefulness of inhibitors of gastrin expression and release such as powerful somatostatin analogs (Sandostatin) or blockers of COX-2 (coxibs) in the control of GC development and progression as chemopreventive agents. Comparative genomic and proteomic is the key in identifying biomarkers in host and bacterium for the prediction of gastric cancer in Hp-infected patients.

Background: Helicobacter pylori infection of Mongolian gerbils is an established model of gastric carcinogenesis, but gastric secretory aspects of this carcinogenesis have not been studied., Methods: The effects of single intragastric inoculation of gerbils with H. pylori strain (cagA+ vacA+, 5 x 10(6) CFU/ml) or vehicle (saline) were examined at 1, 2, 4, 6, 9, 12 and 30 weeks from inoculation. Gastric morphology, the presence of H. pylori using the rapid urease test, the density of H. pylori and 16S rRNA and the plasma gastrin and somatostatin were determined., Results: H. pylori was detected in gastric mucosa in all infected animals. Basal gastric acid in gerbils was reduced by about 50% after H. pylori inoculation. Early lesions seen at 4 weeks after H. pylori inoculation consisted of chronic gastritis with thickened mucosal folds, oedema, congestion and mucosal lymphocytic infiltration. Adenomatous hyperplasia with cellular atypia with increased mitotic activity and the formation of apoptotic bodies and visible erosions and ulcerations were observed at 12-30 weeks after inoculation. The atypical gastric glands were situated 'back-to-back', suggesting gastric pre-cancer. The gastric blood flow in H. pylori-infected gerbils was significantly lower than that in the controls. Six- to seven-fold increase in plasma gastrin levels combined with significant fall in gastric somatostatin contents and the intraepithelial neoplasia were noticed in gerbils at all tested periods., Conclusion: H. pylori-infection in gerbils resulted in gastric pre-cancer associated with functional changes, such as suppression of gastric secretion and impairment of both gastric mucosal microcirculation and the gastrin-somatostatin link.

Background: Several studies have shown a link between gastrin and gastric cancer, both in humans and animals, especially infected with Helicobacter pylori (H. pylori). However, the exact role of hypergastrinemia in gastric carcinogenesis remains still undetermined. The aim of the present study was to evaluate the interaction between gastrin, cyclooxygenase-2 (COX-2), hepatocyte growth factor (HGF) and apoptosis-related proteins (Bax, Bcl-2, caspase-3, survivin) in cultured gastric epithelial cancer cells., Material and Methods: In the present study, gastric cultured cancer cells (KATO III cells) were exposed to increasing concentrations of gastrin (1-1000 nM). Cells incubated with culture medium alone, without added gastrin, served as controls. Using RT-PCR and Western blot, we examined the mRNA and protein expression for COX-2, HGF and apoptosis-related proteins (Bax, Bcl-2, caspase-3 and survivin). In addition, the gene expression of gastrin and gastrin receptor (CCK-2) as well as the release of gastrin in culture medium in the unstimulated cells were examined by RT-PCR and RIA, respectively. The apoptosis rate in cells was measured by flow cytometric analysis., Results: The present study shows that the gastric cultured epithelial cells exhibit the expression of gastrin and CCK-2 receptors and release of gastrin into the culture medium. The epithelial gastric cancer cells incubated with gastrin showed a concentration-dependent increase of COX-2 and HGF expression. Although no significant changes in apoptosis rate were observed, the exposure of these cells was associated with a dose-dependent increase in the expression of antiapoptotic proteins Bcl-2 and survivin., Conclusions: This study demonstrates that 1) gastrin stimulates the gene and protein expression of COX-2 and HGF in human cultured gastric cancer cells and 2) gastrin shows antiapoptotic activity through the upregulation of Bcl-2 and survivin.

Gastric cancer is one of the most common malignant tumors of the gastrointestinal tract. However, the molecular pathways involved in the regulation of gastric carcinogenesis are not completely elucidated. In the last decade, basic cancer research has been focused on the deregulation of apoptosis as a central event in the process of carcinogenesis. Caspase-3 and survivin are regulators of apoptosis and have been implicated in the development of gastric cancer. The aim of the present study was to compare the expression of mRNA and protein for survivin and caspase-3 in the gastric cancer and in the cancer margin with that in normal human gastric mucosa. Fifteen patients with advanced gastric cancer (all H. pylori-positive) and 15 matched control subjects with normal gastric mucosa were included in this study. The biospy specimens for histology and for molecular analyses were taken from gastric tumor, tumor surrounding gastric mucosa and in normal patients from the mucosa of antrum and corpus. Survivin mRNA expression was very weak, but detectable, in the normal gastric mucosa. However, at the protein level, no expression for survivin was detected in the normal gastric mucosa. In the biopsy specimens from tumor and surrounding gastric mucosa, a significant increase in survivin mRNA and protein expression was observed. The expression of survivin was higher in the tumor than in the tumor margin. The mRNA and protein expression of caspase-3 was detected in the gastric mucosa of normal subjects. In gastric cancer only the expression of procaspase-3 was observed, while the expression of active caspase-3 was completely undetectable. In the gastric mucosa surrounding gastric cancer, no gene and protein expression for caspase-3 was detected. We conclude that the changes in the level of caspase-3 and survivin play an important role in the transformation from normal gastric mucosa to gastric career.

Background: Numerous studies have shown an association between Helicobacter pylori (Hp) infection and gastric cancer (GC)., Study: This study was designed to determine the role of cytotoxin-associated gene A (CagA)-positive Hp infection, serum amidated gastrins and their precursor, progastrin, gastric acidity and serum pepsinogen I (PG-I) levels in gastric cancerogenesis in 74 cancer patients and in 77 age- and gender-matched controls. Serum IgG antibodies to Hp and CagA and levels of IL-8 and PG-I were measured by ELISA, while progastrin and amidated gastrin by specific radioimmunoassay., Results: The overall Hp and CagA seropositivity in GC patients were significantly higher (82 and 60%) than in matched controls (61 and 27%, respectively). Progastrin and amidated gastrin levels over their cutoff points (122 and 32 pM, respectively) were found in a significantly larger number of GC (59.4 and 44.5%) than in controls (9.0 and 16.8%, respectively). Histologically, all these GCs with increased serum progastrin and amidated gastrins were of intestinal type and showed CagA and Hp seropositivity. Serum IL-8 and gastric pH, above their cutoff points (pH >4.5), and serum PG-I level below its cutoff point (44.2 microg/l) were observed in a significantly higher number of GC patients as compared to controls., Conclusions: (1) GC patients have higher Hp and CagA seroprevalence than matched controls, confirming that CagA-positive Hp infection is associated with higher risk of GC; (2) serum levels of amidated gastrins and their precursor, progastrin, as well as IL-8 are significantly higher, while serum PG-I levels are reduced in intestinal type GC compared to controls, and (3) determination of high serum progastrin, amidated gastrins and IL-8 combined with low serum PG-I may be useful biomarkers of GC., (Copyright 2003 S. Karger AG, Basel)

Background: Despite numerous epidemiological studies, the association between Helicobacter pylori infection and gastric cancer (GC) remains unexplained. This study was designed to determine the seropositivity of H. pylori and cytotoxin-associated gene A (CagA), serum gastrin and interleukin-8 (IL-8) levels as well as basal intragastric pH and maximal histamine-induced gastric acid outputs (MAO) in a large series of GC patients and controls., Methods: 337 GC patients (118 men and 219 women; median age 59.4; range 21-87) and 337 controls randomized for sex and age entered the study. Serum IgG antibodies to H. pylori and CagA and serum levels of IL-8 were measured by enzyme-linked immunosorbent assay, while serum-amidated gastrin was determined by specific radioimmunoassay and correlated with gastric luminal pH., Results: The numbers of GC patients and controls involved in the study in various age groups, ranging from 20 to > 70 years, were similar, but overall H. pylori IgG seropositivity in GC patients was significantly higher (90.8%) than in controls (79.2%). The overall CagA seropositivity in GC patients was about double (58.2%) that in controls (25.2%). Serum gastrin levels over the calculated cut-off value (38.88 pM/L) were found in several-fold larger number in GC patients (48%) than in controls (8.3%) and. similarly, serum IL-8 values over the cut-off point (1.77 pg/mL) occurred in almost all (99.7%) GC patients but in only a few controls (0.3%). Basal intragastric pH above the cut-off point (pH = 4.50) was observed in about 58.2% of GC patients compared to 15.1% in controls, and strong correlation between the serum gastrin and gastric pH was found in GC but weak in controls. The cut-off value for MAO was 12.3 mml/h; MAO below this cut-off value occurred in 89.9% of GC patients and in only 4.7% of controls. A summary odds ratio (SOR) in GC for H. pylori IgG was 2.59 (95% Cl: 1.61-4.22) for CagA - 4.12 (95% Cl; 2.93-5.8), for serum gastrin - 10.25 (95%; 6.47-16.47) and for MAO - 15.2 (95% Cl; 9.45-39.82). Multivariable analysis of serum gastrin, IgG and CagA, and luminal pH and MAO values revealed that only gastrin and CagA have significant influence on GC formation (OR > 1 in logistic regression)., Conclusions: 1. CG patients show significantly higher H. pylori IgG and CagA seropositivity than dyspeptic age- and gender-matched controls, confirming that gastric infection with CagA expressing H. pylori greatly increases the risk of GC. 2. Serum gastrin levels in GC but not in controls are correlated with the rise in intragastric pH, indicating that excessive gastrin release in GC is affected by lower intragastric pH. 3. Serum gastrin level and CagA seropositivity are significantly increased in the majority of GC patients, and are the only variables in multivariable analysis to have a predominant influence on GC formation, which suggests that both these parameters may be implicated in H. pylori-related gastric carcinogenesis. 4. H. pylori-infected GC patients produce significantly more IL-8 than do non-GC controls, probably reflecting CagA-positive H. pylori-associated gastritis.

Aims: To determine whether an adequate histological diagnosis of gastric polyps can be attained on the basis of forceps biopsy., Patients and Methods: In a prospective multicentre study, 194 patients with 222 endoscopically removable gastric polyps (>or=5 mm) underwent forceps biopsy and complete polypectomy. Patients with fundic gland polyps and polyposis syndrome were not included. Specimens were evaluated by primary and reference pathologists, and the complication rate of gastric polypectomy was also determined., Results: Of the 222 polyps, histological examination of the polypectomy specimens revealed tumour-like lesions in 77% (10% focal foveolar hyperplasia, 59% hyperplastic polyps, 4% inflammatory fibroid polyps, 4% other polyps) and neoplasia in 19% (10% tubular adenoma, 2% tubulovillous adenoma, 1% high grade intraepithelial neoplasia, 6% adenocarcinoma). When biopsy results were compared, complete agreement was found in 124 cases (55.8%) and, in an additional 77 cases (34.7%), the clinically important differentiation between tumour-like lesions and neoplasia was possible. However, relevant differences were found by the reference pathologist in six cases (2.7%), the most common reason being failure of biopsy to reveal foci of carcinoma in hyperplastic polyps. Bleeding was observed after polypectomy in 16 patients (7.2%), in 15 of whom it was managed conservatively., Conclusions: We recommend complete removal by an experienced endoscopist of all epithelial gastric polyps larger than 5 mm after thorough individualised risk-benefit analysis.

Background: Epidemiological and animal studies demonstrated a link between gastric cancer (GC) or mucosal associated lymphoid tissue (MALT) lymphoma and chronic infection with Helicobacter pylori (H. pylori). The exact mechanism responsible for the development of GC and MALT-lymphoma in H. pylori-infected patients still remains obscure. This report is designed to overview the molecular biology, especially the gene expression and histochemical manifestation of gastrin and other growth factors such as transforming growth factor alpha (TGF alpha) and hepatocyte growth factor (HGF) in the GC before and after eradication of H. pylori. Furthermore, gene expression of cyclooxygenase-1 (COX-1) and COX-2 and apoptosis-related proteins such as Bax and Bcl-2 are discussed., Material and Methods: The findings originate from two series of patients; Series I involving 337 GC patients and 400 age- and gender-matched controls and series 2 including 20 MALT-lymphoma patients and 40 matched controls., Results: An overall H.pylori-seropositivity reached about 80% in GC and about 90% in MALT-lymphoma, significantly higher than in non-cancer controls (60%). The prevalence of CagA-positive strains was about twice as high (about 70%) in GC and MALT-lymphomas as in sex- and age-matched controls. Expression of gastrin was detected in antrum of all tested patients but also in majority (90%) of GCs and MALT-lymphomas tumor tissue. HGF and TGF alpha were expressed more frequently in GC tissue than in normal fundic mucosa. COX-1 was similarly expressed in GC and MALT as in intact mucosa, while COX-2 mRNA was detected only in tumor tissue, being attenuated by H.pylori eradication in GC and abolished by this therapy in MALT-lymphoma. The plasma levels of alpha-amidated gastrin in GC and MALT were several folds higher than in controls. Gene expression of bcl-2 was detected in all, while bax--only in about 50% of GC samples., Conclusions: Infection with H. pylori, especially that expressing CagA-positivity, is primum movens in developing GC and MALT-lymphoma and the upregulation of growth factors, particularly of gastrin, and COX-2 and dysregulation of the Bax/Bcl-2 system seem to contribute to gastric cancerogenesis.

Objective: The aim of this study was to investigate autofluorescence spectroscopy using violet-blue excitation light for the in vivo diagnosis of GI cancer during routine endoscopy., Methods: Fluorescence spectra were obtained from normal mucosa and cancerous lesions of the esophagus and stomach. The spectroscopic system used comprised a special light source capable of delivering either white or violet-blue light to induce autofluorescence of tissue via the endoscope. Endogenous fluorescence spectra emitted by the tissue were recorded with a fiberoptic probe and analyzed with a spectrographic detector system consisting of a polychromator with a photodiode array and an optical multichannel analyzer. The data of each spectrum were sampled within the range of 450-700 nm and stored in a personal computer., Results: Esophageal squamous cell cancer, adenocarcinoma of the esophagus, and adenocarcinoma of the stomach show specific differences in the emitted fluorescence spectra compared with normal mucosa., Conclusions: Light-induced fluorescence spectroscopy might be a useful tool for the endoscopic in vivo detection of dysplasia and early carcinoma in the upper GI tract. Further trials are needed to test the validity of this new optical detection system.

Background: Gastric cancer is one of the most frequent neoplasms and a leading cause of the death world-wide. In recent years, epidemiological and animal studies demonstrated a link between gastric cancer and chronic infection with H. pylori. The exact mechanism responsible for the development of gastric cancer in H. pylori-infected patients still remains unclear. There is evidence that the up-regulation of certain growth factors could play an important role in the promotion of the gastric carcinogenesis., Aims: The present study was designed to determine the gene expression of major known growth factors such as transforming growth factor alpha (TGFalpha), hepatocyte growth factor (HGF) and gastrin in the gastric cancer tissue, the surrounding mucosa and, for comparison, in the normal gastric mucosa. Furthermore, the luminal and plasma levels of gastrin in patients with gastric cancer were determined. In addition, the gene and protein expressions of apoptosis-related proteins such as Bax and Bcl-2 were investigated by reverse transcription-polymerase chain reaction and Western blot. Twenty-five gastric cancer patients and 40 age- and gender-matched control subjects hospitalized with non-ulcer dyspepsia were included into this study., Results: An overall H. pylori-seropositivity among gastric cancer patients was about 72% and was significantly higher than in the controls (56%). The prevalence of CagA-positive strains was also significantly higher among gastric cancer patients than in controls (56% vs. 32%). The gene expression of HGF and TGFalpha was detected more frequently in gastric cancer tissue samples than in normal gastric mucosa (52% vs. 12% for HGF and 48% vs. 24% for TGFalpha). The extent of protein expression in Western blotting analysis for HGF and TGFalpha correlated with the mRNA expression of these factors. Gene expression of gastrin was detected in the antrum of all tested patients and in the majority (84%) of gastric cancer patients. The median plasma and luminal concentrations of gastrin in gastric cancer patients were significantly higher than in controls. The gene expression of bcl-2 was detected in all (100%) and that of proapoptotic bax only in 56% of gastric cancer samples. In comparison to the surrounding non-tumorous tisssue, the gene expression of bax was significantly down-regulated and the gene expression of bcl-2 was up-regulated in gastric cancer tissue. At the protein level, Bax was not detectable and Bcl-2 was seen in 80% of gastric cancer samples., Conclusions: It is concluded that the patients infected with H. pylori, especially with CagA-positive strains, are at a higher risk of developing a gastric cancer. An increased production and release of gastrin, as well as an over-expression of growth factors such as HGF and TGFalpha, might contribute to the gastric carcinogenesis. In addition, a dysregulation of the Bax/Bcl-2 system with significant up-regulation of Bcl-2 is observed in gastric cancer.

Background: Tumors arising in the stomach have worldwide distribution and the infection with Helicobacter pylori (HP) has been implicated in causation of this disease. The HP discovery, which is considered as the greatest advance of gastroenterology at the dawn of 3rd millennium, is accompanied by hypergastrinemia, which seems to play a key role in gastric cancerogenesis but no study was undertaken to assess the relationship between the HP infection and coexpression of gastrin and cyclooxygenases (COX), the rate limiting enzymes in the eicosanoids production., Aims: Since gastrin is recognized as a effective gastric mitogen, it could be capable to induce COX-2, a potent tumor growth promoting and angiogenic factor, we decided 1) to compare the seroprevalence of HP and its cytotoxic protein, CagA, in gastric cancer patients with those in age- and gender-matched controls; 2) to determine the gene expression of gastrin and its receptors (CCK(B)-R) in gastric cancer, 3) to assess the plasma levels, gastric lumen and tumor tissue contents of gastrin and 4) to examine the mRNA and enzyme protein expression of COX-1 and COX-2 in cancer tissue and intact gastric mucosa before and after HP eradication., Material and Methods: The trial material included 20 patients with gastric cancers and 100 age- and gender-matched controls. Anti-HP and anti-CagA IgG seroprevalence was estimated by specific antisera using ELISA tests. Gene expressions of gastrin, CCK(B)-R, COX-1 and COX-2 was examined using RT-PCR with GAPDH as a reference and employing Western blot for COX-2 expression, while gastrin was measured by RIA., Results: The seroprevalence of HP, especially that expressing CagA, was significantly higher in gastric cancers than in controls. Both gastrin and CCK(B)-R mRNA were detected by RT-PCR in the cancer tissue and similarly COX-2 mRNA and protein were found in most of cancers and in the HP infected antral mucosa but not in HP eradicated patients in whom only cancer tissue but not gastric mucosa expressed COX-2. The gastric cancer tissue contained 20 times more of immunoreactive gastrin than the HP infected antral gastric mucosa and following HP eradication the gastrin content in the tumor and antrum showed a marked and significant reduction. No significant change in CCK(B)-R expression was noticed before and after HP eradication in the tumor and the corpus mucosa., Conclusions: 1). Gastric carcinoma coexpresses gastrin, its receptors (CCK(B)-R), and COX-2; 2) HP infection may contribute to gastric cancerogenesis via gastrin andCOX-2 that may account for the stimulation of tumor growth, angiogenesis, and reduction in apoptosis 3) HP positive patients developing gastric cancer should be considered for HP eradication to reduce the HP provoked hypergastrinemia and COX-2 overexpression in the tumor tissue.

Helicobacter pylori, infecting more than 50% of the world population, results in gastritis, usually located in the antral portion of the stomach, accompanied by hypergastrinemia, the key factor in gastric and colorectal carcinogenesis. Excessive mucosal cell proliferation for many years may eventually result in gastric atrophy, cell mutation and transformation of gastric mucosal cells into gastrin-producing cells, which also express gastrin receptors serving to stimulate cell proliferation and tumor growth. These processes may be completed by the expression of cyclooxygenase-2 (COX-2) as an inflammation enzyme to release excessive amounts of PGE(2), leading to further proliferation, reduction in apoptosis, angiogenesis and tumor growth. H. pylori eradication results in complete regression of MALT lymphoma and subsequent normalisation of excessive gastrin release and COX-2 expression. Reduction of gastrin by active immunisation (gastrimmune), blocking of gastrin receptors with specific blockers and suppression of COX-2 might be helpful in inhibiting tumor growth and invasion.

Background: The present article describes light-induced autofluorescence spectroscopy using violet-blue excitation light for endoscopic in vivo measurements in the upper GI tract. The spectra of normal mucosa, cancer, and dysplastic lesions of the esophagus and stomach are presented and compared., Methods: Over 120 spectra were obtained in 11 patients of normal mucosa and malignant lesions in the esophagus and stomach during routine endoscopy. A special light source capable of delivering either white or violet-blue light was used for the excitation of tissue auto-fluorescence via the endoscope. Endogenous fluorescence spectra emitted by the tissue were collected with a fiberoptic probe and analyzed with a spectrograph. After spectrographic measurements biopsies were taken for definitive classification of histopathologic status., Results: As compared with normal mucosa, (pre) cancerous lesions were associated with special changes in the emitted fluorescence spectra. The spectrographic records were influenced by the intensity of the illumination and on the position of the probe (distance and angle)., Conclusion: Fluorescence spectroscopy with a slightly modified conventional light source might be useful for the endoscopic detection of dysplasia and early-stage carcinoma in the upper GI tract. Prospective trials need to determine the sensitivity and specificity of this new method.

Numerous epidemiological studies demonstrated the association between Helicobacter pylori (H. pylori) infection and gastric cancer but the mechanism of the involvement of H. pylori in gastric cancerogenesis remains virtually unknown. This study was designed to determine the seropositivity of H. pylori and cytotoxin associated gene A (CagA), serum gastrin and gastric lumen gastrin levels under basal conditions and following stimulation with histamine in gastric cancer patients and controls. 100 gastric cancer patients aging from 21 to 60 years and 300 gender- and age-adjusted controls hospitalized with non-ulcer dyspepsia (NUD) entered this study. 13C-Urea Breath Test (UBT), serum immunoglobulin (IgG) antibodies to H. pylori and CagA were used to assess the H. pylori infection and serum levels of IL-1beta, IL-8 and TNFalpha were measured by enzyme-linked immunosorbent assay (ELISA) to evaluate the degree of gastric inflammation by H. pylori . Gastrin-17 mRNA and gastrin receptors (CCK(B)) mRNA expression in gastric mucosal samples taken by biopsy from the macroscopically intact fundic and antral mucosa as well as from the gastric tumor was determined using RT-PCR. The overall H. pylori seropositivity in gastric cancer patients at age 21-60 years was about 92%, compared, respectively, to 68%, in controls. A summary odds ratio (OR) for gastric cancer in H. pylori infected patients was about 5.0 . The H. pylori CagA seropositivity in gastric cancer patients was about 58.5% compared to 32.4% in controls, giving the summary OR for gastric cancer in CagA positive patients about 8.0. The prevalence of H. pylori- and H. pylori CagA-seropositivity was significantly higher in cancers than in controls, irrespective of the histology of gastric tumor (intestinal, diffuse or mixed type). Median IL-1beta and IL-8 reached significantly higher values in gastric cancer patients (9.31 and 30.8 pg/ml) than in controls (0.21 and 3.12, respectively). In contrast, median serum gastrin in cancers (as total group) was several folds higher (62.6 pM) than in controls (19.3 pM). Also median luminal gastrin concentration in gastric cancer patients was many folds higher (310 pM) than in controls (20 pM). This study shows for the first time that cancer patients are capable of releasing large amounts of gastrin into the gastric lumen to increase luminal hormone concentration to the level that was recently reported to stimulate the growth of H. pylori. There was no any correlation between plasma gastrin levels and gastric luminal concentration of gastrin suggesting that: 1) luminal gastrin originates from different source than plasma hormone, most probably from the cancer cells, 2) cancer cells are capable of expressing gastrin and releasing it mainly into the gastric juice and 3) the gastric cancer cells are equipped with gastrin-specific (CCK(B)) receptor so they exhibit the self-growth promoting activity in autocrine fashion. This notion is supported by direct detection of gastrin mRNA and gastrin receptor (CCK(B)-receptors) mRNA using RT-PCR in cancer tissue. To our knowledge this is the first study showing an important role of gastrin as self-stimulant of cancer cells in patients infected with H. pylori. Basal and histamine maximally stimulated acid outputs were significantly lower in gastric cancer patients than in controls despite of enhanced gastrin release, particularly in cancer patients and this might reflect the mucosal inflammatory changes (increased serum levels of proinflammtory interleukins - IL-1beta and IL-8), that are known to increase gastrin release. We conclude that: 1) H. pylori infected patients, particularly those showing CagA-seropositivity, are at greatly increased risk of development of gastric cancer, 2) H. pylori-infected cancer patients produce significantly more IL-1beta and IL-8 that might reflect an H. (ABSTRACT TRUNCATED)

Background: Dysplasia and early cancer of the upper gastrointestinal (GI) tract often are undetected at white-light endoscopy. We describe oral administration of 5-aminolevulinic acid for the in vivo photodynamic diagnosis of premalignant and malignant lesions during endoscopy., Methods: Four patients with known gastric adenoma (n = 1), macroscopically undetected but histologically proven esophageal squamous cell cancer (n = 1), suspected early cancer of the esophagus (n = 1), and multiple duodenal adenomas (n = 1) were sensitized with 5-aminolevulinic acid administered orally (15 mg/kg body weight). Photodynamic diagnosis was conducted after a retention time of 6 to 7 hours with a special light source capable of delivering either white or violet-blue light. Red fluorescence was detected through the gastroscope with an image-intensifying camera., Results: All malignant lesions exhibited red or bluish fluorescence during photodynamic diagnosis. Fluorescence-negative mucosal areas proved to be histologically benign., Conclusion: Fluorescence induced with 5-aminolevulinic acid might be useful for the endoscopic detection of dysplasia and early carcinoma in the upper GI tract. Further investigations are needed to evaluate the sensitivity and specificity of photodynamic diagnosis for different tumor entities.

Background: Radical surgical treatment has been the first choice for early gastric cancer, but high resolution endosonography allows in situ diagnosis with a high sensitivity and specificity and in consequence the option of local endoscopic treatment., Aims: To evaluate photodynamic therapy (PDT) using meso-tetrahydroxyphenyl-chlorin (mTHPC) as the photosensitiser in superficial gastric cancer., Methods: Twenty two patients with superficial early gastric cancer received mTHPC (0.075 mg/kg intravenously) and were treated 96 hours later with red light at 652 nm (20 J/cm2). Tumour response was assessed by endoscopy and extensive biopsy., Results: Endoscopies performed two to three days after PDT showed a haemorrhagic fibrinoid necrosis of the mucosal layer. Complete remission was achieved in 16/22 (73%) patients: 13/16 (80%) with intestinal type cancer and 3/6 (50%) with a diffuse Lauren's carcinoma. The mean follow up period was 12 months and 20 months, respectively. An average of 1.8 treatment sessions was required. Severe side effects were not observed. Seven patients had mild to moderate skin photo-sensivity reactions; 12 had local pain after PDT for 1-10 days., Conclusion: PDT using mTHPC as the photosensitiser represents a safe and efficient method for topical treatment of early gastric cancer, especially of Lauren's intestinal carcinoma. If the preliminary results can be verified in larger patient series and during long term follow up, local treatment of early cancers of the stomach by PDT could be considered as a therapeutic option for selected patients.

Epidemiological studies have consistently shown an association between infection of Helicobacter pylori (Hp) and duodenal ulcer (DU) and gastric cancer. The mechanism of the ulcerogenic effect of Hp has been related to excessive gastrin release, gastric acid hypersecretion and gastric metaplasia in duodenum. The implication of Hp in gastric carcinogenesis has not been explained. In this study, mucosal expression of EGF and TGF alpha and luminal release of EGF as well as basal and pentagastrin-stimulated acid secretion and plasma gastrin levels have been determined in healthy subjects, gastric carcinoma and DU patients. It was found that Hp positive DU patients show excessive gastrin release and gastric acid secretion combined with increased expression and luminal release of EGF and TGF alpha. These changes returned to normal values two years after the eradication of Hp. Gastric cancer patients also showed increased expression of EGF and TGF alpha and highly increased plasma gastrin but their gastric acid secretion was markedly reduced possibly due to atrophy of oxyntic mucosa. This study indicates that overexpression of growth factors in gastric mucosa may be implicated in the pathogenesis of both duodenal ulcer and gastric cancer and that Hp positive hypochlorhydric and hypergastrinemic patients may be predisposed to development of gastric cancer.

Introduction and Aim of Study: As there are no reports of studies comparing different self-expanding metal stent types the results obtained with three stent types in 73 patients (58 men, 15 women; mean age 65 [43-90] years who had a total of 82 implantation were analysed., Patients and Methods: 31 Wallstents were implanted in 23 patients, 31 Ultraflex stents (all without covering) in 30 patients, and 20 Gianturco-Z stents (with covering) in 20 patients. The three groups of patients did not differ significantly with respect to degree of dysphagia, frequency of previous treatment, length of stenosis by tumour, tumour localization and histological tumour type. Six patients, treated with the Gianturco-Z stent, had an tracheo-oesophageal fistula., Results: All 82 implantations were technically successful. Complete occlusion was achieved in all patients with fistulas, as proven radiologically. Serious early complications, namely stent migration, occurred in two patients (2.4%). The degree of dysphagia improved equally in all three groups (Wallstent, from 2.0 to 0.7; Ultraflex from 2.2 to 0.9, Gianturco-Z from 2.1 to 0.5 (not significant). The median follow-up time differed: 89 days for the Wallstent group, 129 for the Ultraflex group and 77 days for the Gianturco-Z group. Tumour ingrowth was the main problem with the non-covered stents. Accordingly, there were 43% reinterventions with the Wallstent, 37% with the Ultraflex and 20% with the Gianturco-Z stents., Conclusions: Self-expanding metal stents improve palliative treatment of stenosing tumours of the oesophagus and cardia, particularly in view of the low complication rate (< 3%) in the early postimplantation phase. But technical improvements are needed to reduce the number of reinterventions for restenosis in the follow-up period.

Photodynamic treatment (PDT) of malignant tumours rests on the intravenous administration of a photosensitizer, which is predominantly in tumour tissue, and subsequent activation of this substance with light of a specific wavelength. The method was used in a 76-year-old man who had undergone a 2/3 gastric resection for ulcer in 1948 and was now found to have a carcinoma of the stump at the anastomosis. He refused surgical resection, but accepted PDT. 48 hours after intravenous administration of the photosensitizer dihematoporphyrin ether-ester (2 mg/kg) the 1.5 x 1.0 cm tumour was irradiated with an argon ion laser pumped colour laser system at a wavelength of 630 nm and energy density of 150 J/cm3. The irradiation was performed under endoscopic control via a specially developed applicator which had first been introduced through the biopsy channel of the endoscope. Four weeks after the first treatment biopsies from a 5 mm ulceration in the area of the tumour revealed malignant cell groups, so that a second treatment was undertaken. Two, three and six months later the ulcer was shown to have healed and biopsies were free of tumour. But nine months later tumour cells were again demonstrated and a third PDT was performed. Although biopsies were again free of tumour at the next control, it can not yet be assumed that the tumour has been cured.