A prospective study of the frequency and the topographical distribution of colon neoplasia in asymptomatic average-risk Chinese adults as determined by colonoscopic screening

BACKGROUND

The goal of this study was to determine the frequency of colorectal neoplasia in an asymptomatic Taiwanese population and the topographic distribution of lesions relative to age and gender.

METHODS

Colonoscopy was performed in 1846 consecutive asymptomatic adults undergoing a health evaluation in 2003. Neoplastic lesions were considered advanced if they exceeded 10 mm in size, had a villous component, or contained moderately or severely dysplastic tissue or invasive cancer. Lesions at and proximal to the splenic flexure were considered proximal in location; those distal to the splenic flexure were classified as distal in location.

RESULTS

Of 1741 (94.3%) patients (1041 men, 700 women; mean 52.5 years) enrolled, 1708 (98.1%) underwent total colonoscopy. Of these patients, 263 (15.4%) had colorectal neoplasia; 51 (3.0%) had advanced lesions. A total of 331 lesions were detected; 125 (37.8%) were proximal in location. Two thirds of patients with proximal advanced lesions (66.7%, 10/15) had no distal lesion. The proportion of patients with proximal or proximal plus distal lesions increased with age ( p = 0.027).

CONCLUSIONS

Colonoscopy is an effective primary screening modality for colorectal neoplasia in asymptomatic Chinese patients. Many lesions would be missed, especially in the elderly, if only sigmoidoscopy was used for initial screening.

Interleukin-6 increases vascular endothelial growth factor and angiogenesis in gastric carcinoma

Interleukin-6 (IL-6) is a proinflammatory cytokine associated with the disease status of gastric carcinoma (GC). Vascular endothelial growth factor (VEGF) is a potent tumor angiogenic factor in GC. In this study, we attempted to clarify whether IL-6 can regulate VEGF and angiogenesis in GC. GC samples from 54 surgical specimens were subjected to immunohistochemical examination of IL-6, VEGF, and tumor microvessels, and results showed that IL-6 was positively correlated with VEGF expression and tumor vasculature. We determined VEGF expression in four GC cell lines by ELISA, revealing that GC cells can produce significant amount of VEGF with increasing dose and duration of IL-6 stimulation. Next, a luciferase reporter gene assay was employed to determine the signaling pathway driving the VEGF promoter by IL-6, which showed that the JAK/STAT pathway is involved in the stimulation of VEGF gene expression. The effects of IL-6 on angiogenesis in vitro and in vivo were evaluated by HUVEC studies and the Matrigel plug assay, respectively. Results showed that IL-6 effectively promoted HUVEC proliferation and tube formation in vitro and Matrigel plug vascularization in vivo, primarily by inducing VEGF in GC. This study provides evidence that the multifunctional cytokine, IL-6, may induce VEGF expression which increases angiogenesis in gastric carcinogenesis.

Heart rate variability in patients with different manifestations of gastroesophageal reflux disease

BACKGROUND

Autonomic nervous dysfunction has frequently been observed in patients with gastroesophageal reflux diseases (GERD) and impacts the pathogenesis of GERD. However, the characteristics that distinguish between GERD patients with different manifestations remain unknown.

AIM

To investigate the autonomic nervous function in subgroups of GERD patients.

PATIENTS

Of the 164 participants in this study, 57 were healthy controls, 34 had non-erosive reflux disease (NERD), 40 had symptomatic esophagitis (SE), and 33 asymptomatic esophagitis (AE).

METHODS

Resting autonomic activity was assessed by measuring the 5-min heart rate variability (HRV) and HRV indices including time-domain parameters (standard deviation of normal-to-normal intervals [SDNN] and root mean square of successive differences [RMSSD]) and frequency-domain parameters (low-frequency power [LF; 0.04-0.15 Hz], high-frequency power [HF; 0.15-0.4 Hz], and LF/HF power ratio). Mental stress was assessed by use of a self-reported questionnaire (Brief Symptom Rating Scale [BSRS]).

RESULTS

HF power was (ANOVA, p=0.041) but time-domain parameters, LF power, LF/HF power ratio, and BSRS parameters were not significantly different between the four groups. A higher HF power was found in examinees with NERD than in those with SE and AE (LSD methods: both p=0.02). When split into two groups (erosive vs. non-erosive), nearly all measures of autonomic tonus were significantly lower in the erosive than non-erosive group. Age and the presence of endoscopic esophagitis influenced the RMSSD and HF power results in the regression analysis. Mental stress or gender did not correlate with any HRV index.

CONCLUSION

In comparison with NERD subjects, autonomic tonus in patients with endoscopically confirmed esophagitis (even without symptom) is lower. This finding may suggest that the structural state of esophagus but not symptomatology dictates autonomic function status.

The interaction of H. pylori infection and NSAIDs in cyclooxygenase-2 mRNA expression in gastric antral, corpus mucosa, and gastric ulcer

BACKGROUND

Although Helicobacter pylori infection and use of nonsteroidal anti-inflammatory drugs (NSAIDs) are the two major causes of gastric ulcer, their interaction remains controversial. We constructed a prospective cohort study to evaluate how these two factors influence the expression of COX-2 mRNA in gastric antral, corpus mucosa, and gastric ulcer.

METHODS

Tissues were obtained by endoscopic biopsy of gastric antral, corpus mucosa, and gastric ulcer. The presence of H. pylori was determined by culture or histology using Giemsa stain. NSAID use was assessed by structured questionnaire and medical record review. The expression of COX-2 mRNA was detected by the TaqMan quantitative RT-PCR system.

RESULTS

H. pylori infection was associated with increased COX-2 expression only in antral mucosa (0.77 +/- 0.13 vs. 0.31 +/- 0.07, P < 0.01). NSAID use was significantly associated with decreased COX-2 expression in ulcer (4.49 +/- 1.50 vs. 9.82 +/- 2.48, P < 0.05) but not in antral or corpus mucosa. Regarding the interaction between H. pylori and NSAID, we found that H. pylori infection was associated with increased COX-2 expression in antral mucosa for both NSAID users and nonusers. In NSAID users, H. pylori infection was not associated with increased COX-2 expression in ulcer edge.

CONCLUSION

H. pylori infection was associated with increased COX-2 expression in gastric antral mucosa for both NSAID users and nonusers, but not in gastric ulcer, where the effect of NSAID inhibition plays a major role. With these observations, we can interpret indirectly that H. pylori eradication does not interfere with gastric ulcer healing in NSAID users.

Ambulatory esophageal pH monitoring by using a wireless system: a pilot study in Taiwan

BACKGROUND/AIMS

A new wireless esophageal pH monitoring device, the Bravo system, had been tested in the US with favorable results over conventional systems. However, its clinical application in eastern countries remains limited. The aim of the study was to assess the efficacy of the Bravo system in an Asian population, and compare it with the western results.

METHODOLOGY

Thirty consecutive patients with clinically evident gastroesophageal reflux disease underwent esophageal pH monitoring by using the Bravo system. The Bravo capsule capable of measuring and transmitting pH data was introduced into the squamocolumnar junction and fixed on the esophageal mucosa through a locking pin. All patients were instructed to carry the receiver for a 48-hour study.

RESULTS

Twenty-nine (97%) of the 30 patients were successfully tested. In most cases (26/30, 87%) the capsules were placed without conscious sedation. All patients had successful capsule placement; however, two of them had failed the initial capsule attachment and required a second capsule. All patients had successful 24-hour recordings (30/30, 100%), while the successful 48-hour recording rate was 97% (29/30). A minor mucosal injury caused by inadvertent capsule extraction was the only complication (1/30, 3.3%).

CONCLUSIONS

Compared to the western experience, the new wireless pH monitoring system achieved a comparable attaching rate and recording efficacy. Potential complication was rare and self-limited.

Prediction of bleeding and stricture formation after corrosive ingestion by EUS concurrent with upper endoscopy

BACKGROUND

Upper endoscopy provides information that can be used to predict complications and to facilitate clinical decisions for patients who have ingested corrosive substances. The role of EUS in corrosive injury has not been investigated. The aim of this study was to determine whether concurrent catheter-probe EUS provides additional information that predicts complications after corrosive injury.

METHODS

Eighteen patients were referred (from 1997 to 2003) for EGD and concurrent EUS within 24 hours after ingestion of a caustic agent. Two patients were excluded (1 pneumoperitoneum, 1 markedly swollen cricoarytenoid cartilage/epiglottis). The severity of injury in the different segments of the esophagus and stomach was graded (0, 1, 2a, 2b, 3a, 3b) by endoscopy and by EUS (0, M, SM, MP, SS). The development of complications during hospitalization and 3-month follow-up were recorded.

OBSERVATIONS

All 16 patients underwent EGD with EUS without complication. The frequency of early and late complications increased as the endoscopic and the EUS severity grades increased. The accuracy of prediction of bleeding or stricture was 100% when endoscopic grade 3a was used as a cutoff. For EUS, the highest accuracy was observed in the prediction of bleeding (75%) and stricture (100%) when EUS grade MP was used as a cutoff.

CONCLUSIONS

EUS can be performed safely within 24 hours of ingestive of corrosive substances. However, when used in conjunction with conventional endoscopic observation, it does not increase the accuracy for prediction of early or late complications. Standard endoscopy alone is sufficient for evaluation and prediction of bleeding and stricture complications after corrosive injury in the upper-GI tract.

Nuclear expression of BCL10 or nuclear factor kappa B predicts Helicobacter pylori-independent status of early-stage, high-grade gastric mucosa-associated lymphoid tissue lymphomas

PURPOSE

A high percentage of early-stage, high-grade gastric mucosa-associated lymphoid tissue (MALT) lymphomas remain Helicobacter pylori dependent. t(11;18)(q21;q21), a genetic aberration highly predictive of H. pylori-independent status in low-grade gastric MALT lymphoma, is rarely detected in its high-grade counterpart. This study examined whether nuclear expression of BCL10 or nuclear factor kappa B (NF-kappaB) is useful in predicting H. pylori-independent status in patients with stage IE high-grade gastric MALT lymphomas.

PATIENTS AND METHODS

Twenty-two patients who had participated in a prospective study of H. pylori eradication for stage IE high-grade gastric MALT lymphomas were studied. The expression of BCL10 and NF-kappaB in pretreatment paraffin-embedded lymphoma tissues was evaluated by immunohistochemistry and confocal immunofluorescence microscopy. The presence of t(11;18)(q21;q21) was identified by a multiplex reverse transcriptase polymerase chain reaction of the API2-MALT1 chimeric transcript.

RESULTS

Aberrant nuclear expression of BCL10 was detected in seven (87.5%) of eight H. pylori-independent and in none of 14 H. pylori-dependent high-grade gastric MALT lymphomas (P <.001). All seven patients with nuclear BCL10 expression had nuclear expression of NF-kappaB, compared with only two of 15 patients without nuclear BCL10 expression (P =.002). As a single variable, the frequency of nuclear expression of NF-kappaB was also significantly higher in H. pylori-independent tumors than in H. pylori-dependent tumors (seven of eight [87.5%] v two of 15 [12.3%]; P =.002). The API2-MALT1 fusion transcript was detected in only one (12.5%) of eight H. pylori-independent lymphomas.

CONCLUSION

Nuclear expression of BCL10 or NF-kappaB is highly predictive of H. pylori-independent status in high-grade gastric MALT lymphoma, and coexpression of these two markers in the nuclei is frequent.

The osteoporotic spine

Osteoporotic vertebral fractures represent the most common type of osteoporotic fracture. They can cause significant morbidity and mortality, including physical, functional, and psychosocial impairments. Screening using fracture risk assessments can identify those at greatest risk. Medical and non-medical comprise appropriate, comprehensive treatment programs. The minimally invasive spine procedures vertebroplasty and kyphoplasty can help to significantly reduce pain and deformity in patients with severe pain and deformity from vertebral fracture.

Effect of interleukin-1beta and glutathione S-transferase genotypes on the development of gastric mucosa-associated lymphoid tissue lymphoma

e tested whether polymorphic variations in glutathione S-transferase genes (GSTM1, GSTT1, GSTP1) and interleukin-1 (IL-1beta and IL-1RN) genes confer susceptibility to mucosa-associated lymphoid tissue lymphomas (MALT) in a Chinese population. The rates of GSTM1, GSTP1, IL-1beta and IL-1RN genotypes did not differ between patients and controls. However, GSTT1 null genotypes were significantly more common in patients with MALT lymphomas (43/75 vs. 138/321, p=0.029; OR=1.8, 95% CI: 1.1-3.0) than in controls. Our results suggest that a glutathione S-transferase defect plays a role in MALT lymphoma.

Promoter polymorphisms of tumor necrosis factor-alpha are associated with risk of gastric mucosa-associated lymphoid tissue lymphoma

Genes involved in regulating antimicrobial immunity and inflammation may modulate the risk of Helicobacter pylori-associated diseases. IL-1 and TNF-alpha are major cytokines detected in H. pylori-infected tissues. We aimed to determine the role of gene polymorphisms for these cytokines and their receptors in 2 distinct H. pylori-related gastric malignancies, adenocarcinoma (GAC) and maltoma. Genotyping for IL-1beta (-31 C/T, -511 C/T), TNF-alpha (-238 G/A, -308 G/A, -857 C/T, -863 C/A, -1031 T/C), TNFR1 (-383 A/C) and TNFR2 (196 G/T) was undertaken for 70 patients with maltoma and 204 patients with noncardia GAC and compared to 210 unrelated healthy controls. Genotype frequencies showed no differences among patients with GAC or maltoma and controls for IL-1beta, TNFR1 or TNFR2. The TNF-alpha -857 T variant was significantly underrepresented in maltoma compared to controls (6.4% vs. 14.3%, p = 0.018), conferring a 3-fold decrease in risk (OR = 0.33, 95% CI 0.15-0.75). Comparison of allele frequencies between GAC and controls failed to show any statistical significance for TNF-alpha polymorphisms. We concluded that TNF-alpha -857 T itself or a neighboring gene may modify the risk of maltoma. The differences in genetic background as well as divergent clinicopathologic features between GAC and maltoma support the notion that fundamental mechanistic differences exist in these 2 well-defined H. pylori-related malignancies.

Sonographic demonstration of duodenobiliary reflux with soda enhancement

Cholangitis rarely occurs after sphincteroplasty if there is no biliary obstruction. We report the case of a patient who developed recurrent cholangitis despite having a patent biliary tract after sphincteroplasty. Duodenobiliary reflux was demonstrated on sonography after enhancement of the reflux flow with a novel oral contrast agent, a carbonated soda beverage. Sonography with contrast enhancement provided by soda solution may prove satisfactory to detect duodenobiliary reflux after sphincteroplasty safely, effectively, and economically.

Unusual sonographic appearance of a gastrointestinal stromal tumor presenting as a large multilocular cystic mass

Cystic change is uncommon in gastrointestinal stromal tumor, (GISTs). This report describes 1 case in which a GIST presented as a large multilocular cystic mass. Sonography of the abdomen showed a huge cystic lesion with multiple septa in the left upper quadrant of the abdomen, compressing the left lobe of the liver. Esophagogastroscopy showed only a small submucosal tumor at the anterior wall of the mid portion of the gastric body. Endoscopic sonography revealed a hypoechoic mass, measuring 0.9 x 0.7 cm, arising from the fourth layer of the anterior wall of the mid portion of the gastric body. A huge cystic tumor, containing multiple septa and continuous with the small submucosal lesion, was found. Doppler signals were detected within the septa. Laparotomy revealed a huge exophytic cystic tumor arising from the stomach. Immunohistochemical analysis confirmed that the lesion was a GIST by detecting expression of the c-kit and CD34 proteins. GIST that has undergone cystic change must be differentiated from other cystic lesions to guide the treatment approach. Imatinib mesylate is a new therapeutic alternative for patients who have advanced GIST, but surgery remains the therapy of choice for resectable disease.

Low prevalence of Helicobacter pylori but high prevalence of cytomegalovirus-associated peptic ulcer disease in AIDS patients: Comparative study of symptomatic subjects evaluated by endoscopy and CD4 counts

BACKGROUND AND AIMS

The role of Helicobacter pylori infection in gastroduodenal lesions might be different between the general population and AIDS patients. The aim of the present study was to compare the prevalence of H. pylori and cytomegalovirus (CMV) infection in AIDS patients and HIV-negative controls. The impact of CD4 lymphocyte counts on H. pylori and CMV infection in the same subjects was also assessed.

METHODS

One hundred and fifty-six patients (52 HIV-positive, 104 HIV-negative) with gastrointestinal symptoms were evaluated with upper gastrointestinal endoscopy and biopsy. Comparison of the prevalence of H. pylori and CMV infection was made by dividing AIDS patients into two groups: those with CD4 counts >100/mm3 and those with CD4 counts <100/mm3, and ulcer and non-ulcer patients.

RESULTS

In comparison with HIV-negative controls, AIDS patients had a lower prevalence of H. pylori infection (P < 0.0001) but a higher prevalence of CMV infection (P < 0.0001). Cytomegalovirus infection was frequently found in AIDS patients with CD4 count <100/mm3, in comparison with those with a CD4 count >100/mm3. In AIDS patients, CMV was more frequently detected in subjects with peptic ulcers (P = 0.0125). Conversely, the prevalence of H. pylori infection in AIDS patients was not different between those with and without peptic ulcers.

CONCLUSIONS

The low prevalence of H. pylori infection and peptic ulcer in AIDS patients suggests a different role of H. pylori infection in peptic ulcer or even a different mechanism of peptic ulcerogenesis in HIV-positive subjects. Cytomegalovirus, rather than H. pylori, may be the main causative pathogen of peptic ulcers in AIDS patients.

Relationship between Helicobacter pylori infection and erosive gastroesophageal reflux disease

BACKGROUND AND PURPOSE

The role of Helicobacter pylori in the pathogenesis of gastroesophageal reflux disease remains controversial. The aims of the study were to assess the factors that influence the severity of erosive esophagitis in Taiwanese and to determine the prevalence of H. pylori infection in symptomatic patents.

METHODS

Patients with erosive esophagitis confirmed by upper endoscopy from January 2002 to December 2002 at National Taiwan University Hospital were enrolled. The severity of erosive esophagitis was graded endoscopically according to the Los Angeles classification. H. pylori infection was determined by pathology and culture of biopsies at the gastric body and/or antrum. A sex-matched control was selected to determine the prevalence of H. pylori infection.

RESULTS

A total of 104 patients were recruited for the study, 3 of whom were excluded due to previous eradication of H. pylori infection. The prevalence of H. pylori infection in the 101 eligible patients with erosive esophagitis was 34.7%, which was significantly lower than the 64.9% prevalence in the control group (p < 0.001). Age and hiatal hernia were significantly associated with the severe erosive esophagitis (odds ratio, 1.05 and 4.44, respectively). H. pylori infection status, gender, smoking, alcohol drinking, and coexistent systemic diseases such as diabetes and hypertension were not correlated with the severity of erosive esophagitis.

CONCLUSIONS

The overall prevalence of H. pylori infection was significantly lower in symptomatic patients with erosive esophagitis than in controls. Age and hiatal hernia were significantly associated with the severity of erosive esophagitis. H. pylori infection was inversely correlated with the occurrence of erosive esophagitis, but was not correlated with its severity.

Modification effects of GSTM1, GSTT1 and CYP2E1 polymorphisms on associations between raw salted food and incomplete intestinal metaplasia in a high-risk area of stomach cancer

Incomplete intestinal metaplasia (IM) is a precursor of stomach cancer. To identify risk factors of incomplete IM, a 2-stage survey was carried out in 1995 among 1,485 residents in Matzu, an area with highest mortality from stomach cancer in Taiwan. There were 312 study subjects including 174 men and 138 women sampled for the gastroendoscopic examination of IM. Information on personal and familial history of stomach cancer, cigarette smoking, alcohol consumption and intake frequency of various salted food items were obtained by personal interview based on a structured questionnaire. Blood samples were collected from each participant. Four biopsies per subject were taken from all subjects at gastroendoscopic examination to diagnose the status of IM pathologically. The Helicobacter pylori in biopsies was detected by the histomorphological or immunochemistry method, and antibodies against H. pylori in serum by the enzyme-linked immunosorbent assay. Plasma level of selenium was determined by atomic absorption spectrometry, plasma level of retinol, alpha-tocopherol, alpha-carotene, and beta-carotene by high performance liquid chromatography, genotypes of glutathione S-transferase (GST) M1 and T1 and cytochrome P450 (CYP) 2E1 by polymerase chain reaction. The significant association between history of stomach cancer among first-degree relatives and incomplete IM was found (odds ratio [OR] = 2.50; 95% confidence interval [CI] = 1.15-5.43). There was no association between H. pylori infection and incomplete IM. Alcohol drinkers for >20 years had an elevated risk compared to non-drinkers (OR = 3.34; 95% CI = 1.19-9.39). No associations between incomplete IM and plasma levels of selenium, retinol, alpha-tocopherol, alpha-carotene and beta-carotene were found. Salted food including salted meat, dehydrated salted vegetables and raw salted seafood consumed at ages of </=15 and 16-30 years old was associated with an increased IM risk with OR ranging from 2-3. More striking associations between incomplete IM and salted food intake were observed among subjects with genotypes of GSTM1 null, GSTT1 non-null and CYP2E1 c1/c1. Our study suggests the importance of gene-environment interaction on the development of incomplete IM.

Simplified 13C-urea breath test with a new infrared spectrometer for diagnosis of Helicobacter pylori infection

BACKGROUND AND AIM

Infrared spectrometry has correlated excellently with mass spectrometry in detecting the ratio of 13CO(2) to 12CO(2) in breath samples. The present study aimed to evaluate the accuracy of the 13C-urea breath test (13C-UBT) using a new model of infrared analyzer.

METHODS

A total of 600 patients who were undergoing upper endoscopy without receiving eradication therapy were entered into the study. Culture, histology, and rapid urease test on biopsies from the antrum and corpus of the stomach were used for the determination of Helicobacter pylori infection. Breath samples were collected before and 20 min after drinking 100 mg 13C-urea in 100 mL water. The optimal cutoff value was determined by the receiver operating characteristic curve.

RESULTS

Of the 586 patients who were eligible for analysis, 369 were positive for H. pylori infection, 185 were negative for H. pylori infection, and 32 were indeterminate. When the appropriate cutoff value was set at 3.5 per thousand, a sensitivity of 97.8%, a specificity of 96.8% and an accuracy of 97.5% were obtained using the 13C-UBT. The accuracy of the 13C-UBT decreased when CO(2) concentration in the breath sample was <2%, as compared with > or = 2% (93.6%vs 97.7%), mainly because of a decrease in specificity (81.8%vs 97.7%). There were 2.7% of patients with Delta13CO(2) values that fell between 3.0-4.5 per thousand, in whom the risk of error was 47%.

CONCLUSIONS

The 13C-UBT performed with infrared spectrometry is a highly sensitive, specific, and non-invasive method for the detection of H. pylori infection. The immediate availability of the test result and technical simplicity make it particularly effective in routine clinical practice.