Metal or plastic stents for preoperative biliary drainage in resectable pancreatic cancer.

INTRODUCTION: In pancreatic cancer, preoperative biliary drainage (PBD) increases complications compared with surgery without PBD, demonstrated by a recent randomised controlled trial (RCT). This outcome might be related to the plastic endoprosthesis used. Metal stents may reduce the PBD-related complications risk. METHODS: A prospective multicentre cohort study was performed including patients with obstructive jaundice due to pancreatic cancer, scheduled to undergo PBD before surgery. This cohort was added to the earlier RCT (ISRCTN31939699). The RCT protocol was adhered to, except PBD was performed with a fully covered self-expandable metal stent (FCSEMS). This FCSEMS cohort was compared with the RCT's plastic stent cohort. PBD-related complications were the primary outcome. Three-group comparison of overall complications including early surgery patients was performed. RESULTS: 53 patients underwent PBD with FCSEMS compared with 102 patients treated with plastic stents. Patients' characteristics did not differ. PBD-related complication rates were 24% in the FCSEMS group vs 46% in the plastic stent group (relative risk of plastic stent use 1.9, 95% CI 1.1 to 3.2, p=0.011). Stent-related complications (occlusion and exchange) were 6% vs 31%. Surgical complications did not differ, 40% vs 47%. Overall complication rates for the FCSEMS, plastic stent and early surgery groups were 51% vs 74% vs 39%. CONCLUSIONS: For PBD in pancreatic cancer, FCSEMS yield a better outcome compared with plastic stents. Although early surgery without PBD remains the treatment of choice, FCSEMS should be preferred over plastic stents whenever PBD is indicated. TRIAL REGISTRATION NUMBER: Dutch Trial Registry (NTR3142).

Optimal resource allocation in colonoscopy: timing of follow-up colonoscopies in relation to adenoma detection rates.

BACKGROUND AND STUDY AIMS: The assessment of indications for follow-up colonoscopy may help to improve the allocation of available endoscopy resources. The aim of this study was to assess the timing of early follow-up colonoscopy and surveillance utilization in relation to adenoma detection rate (ADR) at follow-up. METHODS: An assessment of the timing and yield of follow-up colonoscopies was performed in patients with non-inflammatory bowel disease (IBD) in a Dutch multicenter study. The primary outcome was the number of patients with a prior (index) colonoscopy. The necessity for follow-up procedures was assessed using the ADR. RESULTS: Of 4800 consecutive patients undergoing a colonoscopy, 1249 non-IBD patients had undergone an index colonoscopy. Of these, follow-up procedures were performed within 1 year in 27 % (331/1249). Excluding incomplete colonoscopy, incomplete polypectomy, or poor bowel preparation on index, the ADR on early follow-up was 4 % for symptomatic and 26 % for asymptomatic patients. Among the asymptomatic patients with a follow-up colonoscopy at > 1 year (n = 463), an ADR of 23 % (108/463) was found. In 27 % of these patients, the observed surveillance intervals were in accordance with American Gastroenterological Association (AGA) surveillance recommendations; 60 % were classified as over-utilization and 13 % as under-utilization according to the AGA. Optimal utilization follow-up colonoscopies had higher ADRs on follow-up compared with over-utilized procedures (31 % vs. 17 %; P < 0.001). CONCLUSIONS: Follow-up colonoscopy in symptomatic patients within a year has limited value in terms of adenoma detection. A considerable proportion of surveillance colonoscopies are performed too early according to current guidelines, resulting in low detection rates. Both aspects can be targeted for optimal usage in endoscopic capacity.

MMP-2 and MMP-9 in normal mucosa are independently associated with outcome of colorectal cancer patients.

BACKGROUND: Upregulation of the matrix metalloproteinases MMP-2 and MMP-9 in various cancers has been associated with worse survival of the patients. METHODS: We assessed MMP-2 and MMP-9 levels in normal colorectal mucosa from colorectal cancer patients in relation to the course of the disease. RESULTS: A high protein expression of MMP-2 as well as MMP-9 in normal mucosa was found to be correlated with worse 5-year survival. The combination of both parameters was an even stronger prognostic factor. These protein levels were found not to be related to the corresponding single nucleotide polymorphisms of MMP-2 (-1306C>T) and MMP-9 (-1562C>T). Multivariate analyses indicated that the MMP-2 and MMP-9 levels in normal mucosa are prognostic for survival, independent of TNM classification. CONCLUSION: MMP-2 and MMP-9 levels in normal mucosa are indicative of the course of disease in colorectal cancer patients.

MMP-2 geno-phenotype is prognostic for colorectal cancer survival, whereas MMP-9 is not.

The prognostic significance of single-nucleotide polymorphisms (SNPs) and tumour protein levels of MMP-2 and MMP-9 was evaluated in 215 colorectal cancer patients. Single-nucleotide polymorphism MMP-2(-1306T) and high MMP-2 levels were significantly associated with worse survival. Extreme tumour MMP-9 levels were associated with poor prognosis but SNP MMP-9(-1562C>T) was not. Tumour MMP levels were not determined by their SNP genotypes.

Expression of matrix metalloproteinases-2 and -9 in intestinal tissue of patients with inflammatory bowel diseases.

BACKGROUND/AIMS: Matrix metalloproteinases are major contributors in the breakdown and reconstitution of basement membranes and extracellular matrix in pathophysiological processes. We assessed the expression of matrix metalloproteinases-2 and -9 in intestinal tissue of patients with inflammatory bowel disease. PATIENTS/METHODS: Resected tissue specimens from patients with Crohn's disease or ulcerative colitis and control tissue from patients with a colorectal carcinoma were used for enzyme-linked immunosorbent assay, zymography, activity assay, reverse transcription polymerase chain reaction and immunohistochemistry to evaluate the expression of these matrix metalloproteinases. RESULTS: Matrix metalloproteinase-2 and more strongly matrix metalloproteinase-9 protein and mRNA were markedly increased in inflammatory bowel disease tissues, with the highest levels in severely inflamed tissues. Immunohistochemistry showed that matrix metalloproteinase-2 was present in the extracellular matrix of the submucosa, with a lower but more generalised expression in the severely inflamed regions. Matrix metalloproteinase-9 was most prominent in polymorphonuclear leukocytes and was increased, also in activity, in all inflammatory bowel disease tissues. An increased matrix metalloproteinase-9 expression in the extracellular matrix was observed in relation to the severity of inflammation. CONCLUSIONS: Matrix metalloproteinases-2 and -9 are enhanced in the intestinal tissue and seem to be actively involved in the inflammatory and remodelling processes in inflammatory bowel disease, without major differences between CD and UC.

Superoxide dismutases in gastric and esophageal cancer and the prognostic impact in gastric cancer.

The oxidant-antioxidant balance is thought to be important in the initiation, promotion, and therapy resistance of cancer. In the present study, we assessed the expression of the antioxidants manganese superoxide dismutase (Mn-SOD) and copper/zinc superoxide dismutase in gastric and esophageal carcinomas and their relation with clinical outcome. Adenocarcinomas of the stomach (n = 81) as well as squamous cell carcinomas of the esophagus (n = 10) showed an enhanced immunohistochemical expression of Mn-SOD, which was accompanied by a significantly higher tissue level (P < or = 0.007) compared with their corresponding normal mucosa. In contrast, copper/zinc superoxide dismutase was found to be marginally lower in these malignant tissues in comparison with the normal tissues. The superoxide dismutase levels were not found to be associated with major clinicopathological features of the gastric cancer patients. Univariate analysis revealed, however, that a high Mn-SOD level in gastric carcinomas, a low level in the normal gastric mucosa, and a high ratio of these two levels in gastric cancer patients are indicative of a poor overall survival. Multivariate analysis, including all clinicopathological parameters, revealed that the Mn-SOD ratio in particular is an independent prognostic parameter in gastric cancer patients.

Absence of Epstein-Barr virus (EBV) in a gastrointestinal stromal cell tumour (GIST) in an adult human immunodeficiency virus-seropositive patient with past EBV infection.

Gastrointestinal stromal cell tumours (GIST) of the small intestine are rare malignancies. Recently, an association of Epstein-Barr virus (EBV) with malignant stromal cell tumour in young people with AIDS and past EBV infection has been described. We describe a 33-year-old heterosexual male with asymptomatic human immunodeficiency virus (HIV) infection who had had an EBV infection in the past and who presented with an EBV-negative GIST. The association between EBV and malignant stromal cell tumours in young people with AIDS could not be reconfirmed in our adult patient. The relationship between EBV and malignant stromal cell tumours in AIDS patients and the possible pathogenetic role of EBV remains to be established, at least in adults.

Tissue level, activation and cellular localisation of TGF-beta1 and association with survival in gastric cancer patients.

Transforming growth factor-beta1 (TGF-beta1), a tumour suppressing as well as tumour-promoting cytokine, is stored as an extracellular matrix-bound latent complex. We examined TGF-beta1 activation and localisation of TGF-beta1 activity in gastric cancer. Gastric tumours showed increased stromal and epithelial total TGF-beta1 staining by immunohistochemistry. Active TGF-beta1 was present in malignant epithelial cells, but most strongly in smooth muscle actin expressing fibroblasts. Normal gastric mucosa from the same patient showed some staining for total, and little for active TGF-beta1. Active TGF-beta1 levels were determined by ELISA on tissue homogenates, confirming a strong increase in active TGF-beta1 in tumours compared to corresponding normal mucosa. Moreover, high tumour TGF-beta1 activity levels were significantly associated with clinical parameters, including worse survival of the patients. Total and active TGF-beta1 levels were not correlated, suggesting a specific activation process. Of the different proteases tested, active TGF-beta1 levels were only correlated with urokinase activity levels. The correlation with urokinase activity suggests a role for plasmin in TGF-beta1 activation in the tumour microenvironment, resulting in transformation of resident fibroblasts to tumour promoting myofibroblasts. In conclusion we have shown localisation and clinical relevance of TGF-beta1 activity levels in gastric cancer.

Clinical impact of MMP and TIMP gene polymorphisms in gastric cancer.

Gastric cancers express enhanced levels of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs). Single-nucleotide polymorphisms (SNPs) in MMP and TIMP genes may be associated with disease susceptibility and might also affect their antigen expression. We studied the genotype distribution and allele frequencies of SNPs of MMP-2, -7, -8 and -9 and TIMP-1 and -2 in gastric cancer patients in relation to tumour progression, patient survival and tissue antigen expression. The genotype distribution and allele frequencies were similar in gastric cancer patients and controls, except for MMP-7(-181A>G). In addition, the genotype distribution of MMP-7(-181A>G) was associated with Helicobacter pylori status (chi(2) 7.8, P=0.005) and tumour-related survival of the patients. Single-nucleotide polymorphism TIMP-2(303C>T) correlated significantly with the WHO classification (chi(2) 5.9, P=0.03) and also strongly with tumour-related survival (log rank 11.74, P=0.0006). Single-nucleotide polymorphisms of MMP-2, -8, -9 and TIMP-1 were not associated with tumour-related survival. Only the gene promoter MMP-2(-1306C>T) polymorphism correlated significantly with the protein level within the tumours. First-order dendrogram cluster analysis combined with Cox analysis identified the MMP-7(-181A>G) and TIMP-2(303C>T) polymorphism combination to have a major impact on patients survival outcome. We conclude that MMP-related SNPs, especially MMP-7(-181A>G) and TIMP-2(303C>T), may be helpful in identifying gastric cancer patients with a poor clinical outcome.

Matrix metalloproteinase-2 is a consistent prognostic factor in gastric cancer.

In a pioneer study, we showed 10 years ago that enhanced tissue levels of the matrix metalloproteinases (MMPs) MMP-2 and MMP-9 in gastric cancers, as determined by zymography, were related with worse overall survival of the patients. To corroborate these observations, we now assessed MMP-2 and MMP-9 with new techniques in an expanded group of gastric cancer patients (n = 81) and included for comparison MMP-7, MMP-8 and the tissue inhibitors of MMPs, TIMP-1 and -2. All MMPs and TIMP-1 were significantly increased in tumour tissue compared to normal gastric mucosa. Matrix metalloproteinase-7, -8 and -9, and the TIMPs showed some correlations with the clinicopathologic parameters TNM, WHO and Laurén classification, but their levels were not related with survival. Regardless of the determination method used, that is, enzyme-linked immunosorbent assay or bioactivity assay, an enhanced tumour MMP-2 level did not show a significant correlation with any of the clinicopathological parameters, but was confirmed to be an independent prognostic factor in gastric cancer.

Proliferative activity of gastric and duodenal endocrine cells in the rat.

The replicative activity and migration of gastrin, somatostatin and serotonin cells in rat stomach and duodenum was studied using combined immunocytochemistry and autoradiography after 3H thymidine pulse-labeling. Our results show that a small proportion of gastrin, somatostatin and serotonin immunoreactive cells displays proliferative activity. The overall labeling index ranged from 1.3% for gastric endocrine cells to 3.2% for duodenal endocrine cells. In a pulse chase experiment, labeling indices of immunoreactive cells were estimated at several time intervals after 3H thymidine administration. Significant differences in labeling index were not found. Migration of 3H thymidine labeled endocrine cells towards the luminal surface was not found in the stomach nor in the duodenum. It is concluded that 1) these endocrine cells have replicating activity; 2) the replicative activity of endocrine cells is higher in the duodenum than in the stomach; 3) the various cell types do not show significant differences in replicating activity and 4) endocrine cells did not seem to migrate to the luminal surface of the mucosa along with the other epithelial cells.

FMRF-amide immunoreactivity in the mammalian gastroenteropancreatic neuroendocrine system.

The presence of FMRF-amide, a cardioactive tetrapeptide, was studied by immunocytochemistry in human and rat gastric antrum and pancreas, and in the ovine, bovine, canine and rabbit pancreas. In human and rat gastric antrum, numerous cells contained FMRF-amide immunoreactive material. By staining of serial sections and by double staining, colocalization of immunoreactivity for gastrin and FMRF-amide was observed in part of the gastrin cells. In the pancreas of these and the other species, immunoreactivity for FMRF-amide was located both in acinar and islet endocrine cells. Colocalization of FMRF-amide and pancreatic polypeptide was found in a proportion of pancreatic polypeptide cells in the pancreas. FMRF-amide immunoreactivity never colocalized with the other neurohormonal peptides which occur in the gastric antrum and the pancreas. Our observations show that neuroendocrine cells occur in the gastric antrum and pancreas which are exclusively immunoreactive or gastrin and for pancreatic polypeptide respectively. In addition cells occur which show immunoreactivity for FMRF-amide as well as for gastrin in the gastric antrum and with antiserum to FMRF-amide as well as for pancreatic polypeptide in the pancreas. It is concluded that FMRF-amide antibodies probably recognize a substance in G and PP cells which is not identical but may be structurally related to gastrin and pancreatic polypeptide.

Proliferating cell nuclear antigen (PCNA): a new marker to study human colonic cell proliferation.

Immunohistochemistry of the S phase related proliferating cell nuclear antigen (PCNA) was studied as an alternative to ex-vivo bromodeoxyuridine (BrdU) immunohistochemistry for assessment of human colonic cell proliferation. From 16 subjects without colonic disease biopsy specimens were collected from five different sites along the colorectum and processed for BrdU and PCNA immunohistochemistry. The mean proliferation index of PCNA was significantly higher at 133% of the value obtained with BrdU. There was, however, a good correlation between the results from both techniques (r = 0.6275; p < 0.05). Decrease in proliferation index along the colorectum was seen with both staining methods but was clearer with PCNA immunohistochemistry (caecum/ascending colon v rectum: 12.0 v 7.2; p < 0.004). The total number of crypt cells also decreased from proximal to distal (134 to 128; p < 0.06) but at no site correlated significantly with the proliferation index. It is concluded that in clinical cell kinetic studies staining for PCNA may serve as an attractive alternative to the BrdU incorporation assay.

Tissue levels of matrix metalloproteinases MMP-2 and MMP-9 are related to the overall survival of patients with gastric carcinoma.

Proteinases are involved in tumour invasion and metastasis. Several matrix metalloproteinases (MMPs) have been shown to be increased in various human carcinomas. We assessed the levels of MMP-2 (gelatinase A) and MMP-9 (gelatinase B) in 50 gastric carcinomas and corresponding mucosa using quantitative gelatin zymography. Both MMP levels were significantly enhanced in gastric carcinomas compared with adjacent mucosal tissue, showed a relatively poor intercorrelation and no relation was found with histopathological carcinoma classifications according to Laurén, WHO and tumour-node-metastasis (TNM). Cox's multivariate proportional hazards analyses revealed that high carcinomatous MMP values are of prognostic significance for a poor overall survival of the patients, independent of the major clinicopathological parameters.

Superoxide dismutases in relation to the overall survival of colorectal cancer patients.

Reactive oxygen metabolites are implicated in the initiation and promotion of cancer. In addition, oxidant scavengers, such as manganese--(Mn-SOD) and copper/zinc--superoxide dismutase (Cu/Zn-SOD), are thought to contribute to colorectal cancer treatment response. In the present study, the prognostic significance of the Mn- and Cu/Zn-SOD antigen content of normal mucosa and carcinomas of 163 patients with colorectal cancer was evaluated in comparison with major clinicopathological parameters, with respect to the 5-year overall survival. The Mn-SOD content of carcinomas was found to be significantly higher than that of normal mucosa, whereas there was no difference in the Cu/Zn-SOD content between the normal mucosa and carcinomas. No association was demonstrable between the Mn-SOD and Cu/Zn-SOD content of the tissues and the assessed clinicopathological parameters (gender, age, localization, differentiation grade, diameter and Dukes' stage), with the exception of the Cu/Zn-SOD and the differentiation grade of the carcinomas. Univariate analysis showed that a high Mn-SOD content of carcinomas was associated with a poor 5-year overall survival of the patients with colorectal cancer. Multivariate analysis including all clinicopathological parameters revealed that this Mn-SOD parameter was prognostically independent. The Mn- and Cu/Zn-SOD content of normal mucosa and the Cu/Zn-SOD content of carcinomas were not associated with the overall survival of the patients. In conclusion, this study demonstrates that for patients with colorectal cancer the Mn-SOD content of colorectal carcinomas has a significant prognostic value that is independent from major clinicopathological parameters, including Dukes' stage.