Stefan G. M. Meuwissen

Progression from colorectal adenoma to carcinoma is associated with non-random chromosomal gains as detected by comparative genomic hybridisation.

AIMS: Chromosomal gains and losses were surveyed by comparative genomic hybridisation (CGH) in a series of colorectal adenomas and carcinomas, in search of high risk genomic changes involved in colorectal carcinogenesis. METHODS: Nine colorectal adenomas and 14 carcinomas were analysed by CGH, and DNA ploidy was assessed with both flow and image cytometry. RESULTS: In the nine adenomas analysed, an average of 6.6 (range 1 to 11) chromosomal aberrations were identified. In the 14 carcinomas an average of 11.9 (range 5 to 17) events were found per tumour. In the adenomas the number of gains and losses was in balance (3.6 v 3.0) while in carcinomas gains occurred more often than losses (8.2 v 3.7). Frequent gains involved 13q, 7p, 8q, and 20q, whereas losses most often occurred at 18q, 4q, and 8p. Gains of 13q, 8q, and 20q, and loss of 18q occurred more often in carcinomas than in adenomas (p = 0.005, p = 0.05, p = 0.05, and p = 0.02, respectively). Aneuploid tumours showed more gains than losses (mean 9.3 v 4.9, p = 0.02), in contrast to diploid tumours where gains and losses were nearly balanced (mean 3.1 v 4.1, p = 0.5). CONCLUSIONS: The most striking difference between chromosomal aberrations in colorectal adenomas and carcinomas, as detected by CGH, is an increased number of chromosomal gains that show a nonrandom distribution. Gains of 13q and also of 20q and 8q seem especially to be involved in the progression of adenomas to carcinomas, possibly owing to low level overexpression of oncogenes at these loci.

Genomic Alterations in Primary Gastric Adenocarcinomas Correlate with Clinicopathological Characteristics and Survival

Background & aims: Pathogenesis of gastric cancer is driven by an accumulation of genetic changes that to a large extent occur at the chromosomal level. In order to investigate the patterns of chromosomal aberrations in gastric carcinomas, we performed genome‐wide microarray based comparative genomic hybridisation (microarray CGH). With this recently developed technique chromosomal aberrations can be studied with high resolution and sensitivity. Methods: Array CGH was applied to a series of 35 gastric adenocarcinomas using a genome‐wide scanning array with 2275 BAC and P1 clones spotted in triplicate. Each clone contains at least one STS for linkage to the sequence of the human genome. These arrays provide an average resolution of 1.4 Mb across the genome. DNA copy number changes were correlated with clinicopathological tumour characteristics as well as survival. Results: All thirty‐five cancers showed chromosomal aberrations and 16 of the 35 tumours showed one or more amplifications. The most frequent aberrations are gains of 8q24.2, 8q24.1, 20q13.12, 20q13.2, 7p11.2, 1q32.3, 8p23.1–p23.3, losses of 5q14.1, 18q22.1, 19p13.12–p13.3, 9p21.3–p24.3, 17p13.1–p13.3, 13q31.1, 16q22.1, 21q21.3, and amplifications of 7q21–q22, and 12q14.1–q21.1. These aberrations were correlated to clinicopathological characteristics and survival. Gain of 1q32.3 was significantly correlated with lymph node status (p=0.007). Tumours with loss of 18q22.1, as well as tumours with amplifications were associated with poor survival (p=0.02, both). Conclusions: Microarray CGH has revealed several chromosomal regions that have not been described before in gastric cancer at this frequency and resolution, such as amplification of at 7q21–q22 and 12q14.1–q21.1, as well gains at 1q32.3, 7p11.2, and losses at 13q13.1. Interestingly, gain of 1q32.3 and loss of 18q22.1 are associated with a bad prognosis indicating that these regions could harbour gene(s) that may determine aggressive tumour behaviour and poor clinical outcome.

Genomic profiling of gastric cancer predicts lymph node status and survival

Gastric carcinogenesis is driven by an accumulation of genetic changes that to a large extent occur at the chromosomal level. We analysed the patterns of chromosomal instability in 35 gastric carcinomas and their clinical correlations. With microarray competitive genomic hybridization, genomewide chromosomal copy number changes can be studied with high resolution and sensitivity. A genomewide scanning array with 2275 BAC and P1 clones spotted in triplicate was used. This array provided an average resolution of 1.4 Mb across the genome. Patterns of chromosomal aberrations were analysed by hierarchical cluster analysis of the normalized log2 tumour to normal fluorescence ratios of all clones, and cluster membership was correlated to clinicopathological data including survival. Hierarchical cluster analysis revealed three groups with different genomic profiles that correlated significantly with lymph node status (P=0.02). Moreover, gastric cancer cases from cluster 3 showed a significantly better prognosis than those from clusters 1 and 2 (P=0.02). Genomic profiling of gastric adenocarcinomas based on microarray analysis of chromosomal copy number changes predicted lymph node status and survival. The possibility to discriminate between patients with a high risk of lymph node metastasis could clinically be helpful for selecting patients for extended lymph node resection.

The prevalence of gastroesophageal reflux disease in institutionalized intellectually disabled individuals

OBJECTIVE:The prevalence of gastroesophageal reflux disease (GERD) was randomly investigated among Dutch and Belgian intellectually disabled individuals.METHODS:In six institutes including 1607 residents, 435 persons with IQ <50 underwent 24-h esophageal pH-metry and were scored for possible predisposing factors and characteristic reflux symptoms. In 49 (11.2%) cases the test failed because of technical reasons. A pathological pH test was defined as a pH <4 for > 4.5% of the measured time. Subjects with a pathological pH test (patients) were compared with those with a normal pH test (controls).RESULTS:Of the remaining individuals, 51.8% (200/386) showed a normal pH test, whereas 186 showed a pathological pH test (median duration pH <4: 14.2%, range: 4.5–78.4%). As possible predisposing factors scoliosis, cerebral palsy, use of anticonvulsant drugs or other benzodiazepines, and IQ <35 were found, whereas symptoms such as vomiting, hematemesis, rumination, and depressive symptoms were indicative for reflux. At endoscopy reflux esophagitis was diagnosed in 129 of the 186 patients (69.4%). In 61 (47.3%) of 129 patients, grade I, 43 (33.3%) grade II, 25 (19.4%) grade III/IV (Savary-Miller) were found. Barretts esophagus was found in 18 (14.0%) and peptic strictures in five (3.9%) cases.CONCLUSIONS:An abnormal 24-h pH-metry and symptoms suggestive for GERD were documented frequently in a large cohort of institutionalized intellectually disabled individuals. Further endoscopical evaluation confirmed the diagnosis of reflux esophagitis in the majority of these individuals.

Gastroesophageal reflux disease in intellectually disabled individuals: how often, how serious, how manageable?

Gastroesophageal reflux disease (GERD) is an important and frequently occurring problem among intellectually disabled individuals (IDI). Early suspicion and recognition of the presence of GERD in IDI is the cornerstone of adequate management of these patients. The prevalence of GERD among institutionalized IDI with an IQ < 50 is about 50%, with 70% of these reflux patients having endoscopically established reflux esophagitis. In case of symptoms as hematemesis, rumination, or dental erosions, there is an increased risk for GERD. GERD has also been shown to be associated with cerebral palsy, an IQ < 35, scoliosis, and the use of anticonvulsant drugs or benzodiazepines. To establish the diagnosis, 24-h pH measurement or endoscopy should be used in all those intellectually disabled individuals in whom GERD clinically is suspected. The efficacy of proton-pump inhibitors (PPIs) in IDI with GERD is indisputable. In IDI, adults as well as children, PPIs are highly effective, independent of the severity of esophagitis. Marked improvement of symptoms and quality of life can be noticed after medical treatment, thereby decreasing the need for surgery in this complicated group of patients.

Determination of amplicon boundaries at 20q13.2 in tissue samples of human gastric adenocarcinomas by high-resolution microarray comparative genomic hybridization.

Comparative genomic hybridization (CGH) of gastric adenocarcinomas frequently shows gains and amplifications of chromosome 20. However, the underlying genetic lesion is unknown and conventional CGH results do not allow specification of the target region. In order to investigate this chromosomal aberration with a higher resolution and sensitivity, microarray‐based CGH was performed with both scanning and high‐resolution arrays of chromosome 20 in a series of 27 gastric adenocarcinomas. Locus‐specific fragments of genomic DNA from bacterial artificial chromosome (BAC) clones were spotted as microarrays. A scanning array contained a set of 27 BAC clones covering chromosome 20q. A high‐resolution array contained 27 overlapping BAC clones at 20q13.2. This high‐resolution array was used to narrow down the amplicon at 20q13.2 in tumours showing amplification of this chromosomal region with the scanning array. Positive copy number changes on chromosome 20q were detected in 12 of 27 cases (44%). These changes included gain of the whole arm of chromosome 20q in 8 of 27 (30%) cases, amplification restricted to 20q12.1 in one case, and amplifications restricted to 20q13 in three cases (11%). The three tumours showing amplification restricted to 20q13 were analysed further using the high‐resolution array. In one tumour, the whole contig was amplified at a constant level. One of the other two tumours had a clear proximal breakpoint, while the other tumour had a clear distal breakpoint within the 20q13.2 region. The proximal and the distal breakpoint were approximately 800 kb apart. In the present study, an amplicon at 20q13.2 has been narrowed down to 800 kb which is likely to harbour one or more putative oncogenes relevant to gastric carcinogenesis, for which ZNF217 and CYP24 are good candidates. Copyright

Percutaneous endoscopic gastrostomy: Complications and suggestions to avoid them

Objectives Percutaneous endoscopic gastrostomy (PEG) tubes have become an excellent alternative for the long-term management of patients with proximal obstructions of the gastrointestinal tract. However, their use has limitations and can be associated with serious complications. We therefore studied the frequency and severity of complications related to the use of PEG tubes in our clinic. Design All adults (aged 18 years and above) in whom a PEG tube was placed between January 1 1994 and January 1 1999 at the Free University Hospital in Amsterdam were included in this study. In initial cases, the indication and procedure were individually judged according to a liberal protocol. However, after several major complications, a strict procedure protocol was implemented in September 1996. Results During the study period, 263 PEG tubes were placed in 254 patients with head and neck cancer (n = 183; 70%), neurological disorders (n = 52; 20%) or severe upper gastrointestinal motility disorders (n = 28; 11%). In period I, 167 PEG tubes were placed and in period II, 96 PEG tubes were inserted. Patients were followed for a median 111 days. Minor complications occurred in 13% of the patients. Major complications occurred in 8% of the patients. In period I, the percentage of major complications was higher than in period II (9.5% versus 6%). Conclusion PEG tube placement is a safe procedure when performed according to strict guidelines. By doing so, PEG tubes allow optimal feeding for prolonged periods with the occasional need for replacement of the tube. PEG tubes should not be introduced in acutely ill patients, patients with a short life expectancy and preferably not to patients with severe coughing.

Selective gene delivery toward gastric and esophageal adenocarcinoma cells via EpCAM-targeted adenoviral vectors

Application of recombinant adenoviral vectors for cancer gene therapy is currently limited due to lack of specificity for tumor cells. For gastric and esophageal adenocarcinoma, we present here that the relative abundant expression of the primary adenovirus receptor, coxsackie/adenovirus receptor (CAR), on normal epithelium compared to carcinoma favors the transduction of the epithelium. As such, to achieve specific transduction of cancer cells, targeting approaches are required that ablate the binding of the virus to CAR and redirect the virus to tumor-specific receptors. By immunohistochemistry and reverse transcriptase polymerase chain reaction assays, we demonstrate a marked difference in expression of the human epithelial cell adhesion molecule (EpCAM) between normal and (pre)malignant lesions of the stomach and esophagus. Based on this, we explored the feasibility of using EpCAM to achieve gastric and esophageal adenocarcinoma selective gene transfer. Adenoviral vectors redirected to EpCAM using bispecific antibodies against the adenovirus fiber-knob protein and EpCAM specifically infected gastric and esophageal cancer cell lines. Using primary human cells, an improved ratio of tumor transduction over normal epithelium transduction was accomplished by the EpCAM-targeted vectors. This study thus indicates that EpCAM-targeted adenoviral vectors may be useful for gastric and esophageal cancer–specific gene therapy in patients. Cancer Gene Therapy (2001) 8, 342–351

Barrett's adenocarcinomas resemble adenocarcinomas of the gastric cardia in terms of chromosomal copy number changes, but relate to squamous cell carcinomas of the distal oesophagus with respect to the presence of high-level amplifications

Three different cancers predominantly occur at the gastro‐oesophageal junction: squamous cell carcinomas of the distal oesophagus, adenocarcinomas of the distal oesophagus (Barretts carcinomas), and adenocarcinomas of the gastric cardia. The aim of the present study was to investigate how, and to what extent, Barretts carcinoma differs from adenocarcinoma of the gastric cardia on the one hand and squamous cell carcinoma of the distal oesophagus on the other, with respect to chromosomal aberrations and related gene expression. The present study analysed 14 squamous cell carcinomas, 24 Barretts carcinomas, and 16 carcinomas of the gastric cardia. Comparative genomic hybridization revealed chromosomal abnormalities in all cases. Typical chromosomal aberrations for the squamous cell carcinoma type were gains at 3q and 11q13, and losses at 3p, 4q, 9p, 11q, and 13q. In contrast, typical copy number changes for both cardiac and Barretts adenocarcinomas were gains at 2q, 7p, and 13q, and losses at 17p. High‐level amplification occurred in all three groups, but its frequency in the cardiac carcinomas was lower than in the other two groups. In conclusion, squamous cell carcinomas are characterized by chromosomal aberrations which are distinct from those seen in carcinomas of the gastric cardia and in Barretts adenocarcinomas. With respect to Barretts cancer, the chromosomal aberrations more closely reflect the adenocarcinoma phenotype than the squamous origin of the epithelium. Copyright

Nonvariceal upper gastrointestinal bleeding: differences in outcome for patients admitted to internal medicine and gastroenterological services

OBJECTIVE:It has been suggested that admission to a gastroenterology service (GAS) is associated with a better prognosis and lower cost for treatment of gastrointestinal (GI) diseases, such as upper GI bleeding (UGB). However, a large potential bias by higher comorbidity on internal medicine services (MED) could not be excluded from these studies. We therefore compared patients with upper GI bleeding admitted to a gastroenterology or internal medicine department, with special emphasis on prognostic factors, such as comorbidity, and outcome.METHODS:Between 1991 and 1995, 322 patients were admitted to our hospital for UGB. Forty-five patients had variceal and 277 patients had nonvariceal upper GI bleeding (NUGB). Of 232 patients with primary NUGB, 125 were admitted to GAS and 93 to MED. The charts of these patients were revised, comorbidity was carefully recorded, and the Rockall risk score was calculated. All deaths were individually classified as unavoidable, mostly due to severe underlying illness, or potentially avoidable.RESULTS:No differences in delay for endoscopy or treatment were observed between GAS and MED. The rebleeding, surgery, and mortality rates in GAS and MED patients were 11.6%versus 11.5% (NS), 7.8%versus 7.3% (NS), and 2.4%versus 10.8% (p = 0.02), respectively. Rockall scores differed between GAS and MED patients (3.1 ± 1.8 vs 3.7 ± 1.7, p = 0.02). The mortality rate stratified by Rockall score was lower for the GAS patients. However, individual analysis revealed that only three of 13 deaths were potentially avoidable: two of 10 at the MED and one of three at the GAS.CONCLUSION:The lower mortality among nonvariceal upper GI bleeding patients admitted to a gastroenterological service compared to an internal medicine service was mainly due to lesser comorbidity. This effect was not detected by stratification according to Rockall, but shown with analysis of individual patient charts only. The latter underscores the potential pitfalls when comparing outcome or cost of treatment between different medical services.