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E K W Ng

Publications and source records attributed to E K W Ng.

18 recordsLinked to original sources
PubMed2006

Irofulven as first line therapy in recurrent or metastatic gastric cancer: a phase II multicenter study by the Cancer Therapeutics Research Group (CTRG).

BACKGROUND: The purpose of this study was to evaluate the tolerability and efficacy of irofulven, a DNA interacting acylfulvene analog, as first line therapy for patients with recurrent or metastatic gastric cancer. PATIENTS AND METHODS: Twenty-three patients with recurrent or metastatic gastric cancer received irofulven at a dose of 0.45 mg/kg administered intravenously over 30-min infusion (up to a maximum of 50 mg), on days 1 and 8, every 3 weeks. RESULTS: The median number of cycles delivered per patient was 2 (range 1-6). Two patients (9%) had >or= 1-week delay in administration of subsequent cycle of chemotherapy. For the day 8 chemotherapy, dose reductions were required in seven patients (30%); dose omitting occurred in five patients (22%). Grade 3/4 anemia and neutropenia occurred in 22 and 17% of patients, respectively. There was no grade 4 thrombocytopenia and no neutropenic fever was observed. Of the 20 evaluable patients, there were no responses observed, 3 patients had stable disease after 2 cycles of treatment which was not confirmed by a further assessment. Median overall survival was 6.05 months (95% CI 4.55-9.39). CONCLUSIONS: Irofulven was tolerated at the dose of 0.45 mg/kg on days 1 and 8, every 3 weeks but showed no evidence of antitumor activity in patients with advanced gastric cancer.

Adenocarcinoma↗
PubMed2006

Predictors of peptic ulcer rebleeding after scheduled second endoscopy: clinical or endoscopic factors?

BACKGROUND AND STUDY AIMS: In a previous study we demonstrated the efficacy of second-look endoscopy with therapy within 16 - 24 hours after index endoscopy in reducing major recurrent peptic ulcer bleeding. In this study, we sought to identify factors that might predict further rebleeding after this scheduled second-look endoscopy. PATIENTS AND METHODS: We studied 249 patients (181 men, 68 women) with acute bleeding peptic ulcers who were treated at the United Christian Hospital, Hong Kong from 1999 to 2002 and who underwent a scheduled second endoscopy. Those patients who developed rebleeding after the second endoscopy were evaluated, and possible predictive factors for rebleeding were analyzed using a logistic regression model. RESULTS: Of the 249 patients who underwent scheduled second-look endoscopy, 17 patients (6.8 %) developed rebleeding: seven of these patients were treated by another endoscopic therapy; ten patients required surgery. The overall mortality rate was 3.1 %. A logistic regression analysis performed on the possible predictive factors for rebleeding found that the following factors were associated with a significant risk of further rebleeding after scheduled second endoscopy: American Society of Anesthesiologists (ASA) grade III or grade IV status (odds ratio 3.81, 95 % CI 1.27 - 11.44), ulcer size greater than 1.0 cm (odds ratio 4.69, 95 % CI 1.60 - 13.80), and a finding of persistent stigmata of recent hemorrhage at the scheduled second endoscopy (odds ratio 6.65, 95 % CI 2.11 - 20.98). CONCLUSIONS: Endoscopic factors, including large ulcer size and the persistence of endoscopic stigmata of recent hemorrhage are important predictors for recurrent bleeding after scheduled second endoscopy.

Aged↗
PubMed2005

Potential diagnostic and prognostic values of detecting promoter hypermethylation in the serum of patients with gastric cancer.

While there is no reliable serum biomarker for the diagnosis and monitoring of patients with gastric cancer, we tested the potential diagnostic and prognostic values of detecting methylation changes in the serum of gastric cancer patients. DNA was extracted from the pretherapeutic serum of 60 patients with confirmed gastric adenocarcinoma and 22 age-matched noncancer controls. Promoter hypermethylation in 10 tumour-related genes (APC, E-cadherin, GSTP1, hMLH1, MGMT, p15, p16, SOCS1, TIMP3 and TGF-beta RII) was determined by quantitative methylation-specific PCR (MethyLight). Preferential methylation in the serum DNA of gastric cancer patients was noted in APC (17%), E-cadherin (13%), hMLH1 (41%) and TIMP3 (17%) genes. Moreover, patients with stages III/IV diseases tended to have higher concentrations of methylated APC (P = 0.08), TIMP3 (P = 0.005) and hMLH1 (P = 0.03) in the serum. In all, 33 cancers (55%) had methylation detected in the serum in at least one of these four markers, while three normal subjects had methylation detected in the serum (specificity 86%). The combined use of APC and E-cadherin methylation markers identified a subgroup of cancer patients with worse prognosis (median survival 3.3 vs 16.1 months, P = 0.006). These results suggest that the detection of DNA methylation in the serum may carry both diagnostic and therapeutic values in gastric cancer patients.

Adenocarcinoma↗
PubMed2005

Accuracy of endoscopic ultrasonography in diagnosing ascites and predicting peritoneal metastases in gastric cancer patients.

BACKGROUND: Preoperative diagnosis of peritoneal metastases (PM) is difficult in patients with gastric cancer (GC). AIMS: To assess the accuracy of endoscopic ultrasonography (EUS) in diagnosing ascites and its predictability for the presence of PM in GC patients. SUBJECTS: Consecutive patients with newly diagnosed GC from 1998 to 2004 were studied. METHODS: All patients underwent EUS, ultrasound (US), and computed tomography (CT) scan for preoperative staging and the presence of ascites. The results were compared with operative findings. The diagnosis of PM was confirmed by histopathology or peritoneal fluid cytology. RESULTS: A total of 301 patients were recruited and in 250 patients the presence of ascites (n = 93) and PM (n = 71) were confirmed. EUS was more sensitive (87.1%) than combined US and CT scan examinations (16.1%) and operative findings (laparoscopy or laparotomy) (40.9%) in diagnosing ascites. Sensitivity, specificity, positive and negative predictive values, and accuracy for predicting the presence of PM were 73%, 84%, 64%, 89%, and 81% by EUS; 18%, 99%, 87%, 75%, and 76% by combining US and CT scan; and 77%, 94%, 83%, 91%, and 89% by operative findings, respectively. In multivariate logistic regression analysis, EUS detected ascites was the only significant independent predictor for the presence of PM (p<0.001; odds ratio 4.7 (95% confidence interval 2.0-11.2)). CONCLUSION: EUS is a sensitive method for diagnosing ascites which is an important predictive factor for the presence of PM in GC patients.

Adenocarcinoma↗
PubMed2004

Combined sinus tract endoscopy and endoscopic retrograde cholangiopancreatography in management of pancreatic necrosis and abscess.

BACKGROUND: We report our experience of sinus tract endoscopy (STE) and endoscopic retrograde cholangiopancreatography (ERCP) in the treatment of pancreatic necrosis and abscess. METHODS: Thirteen patients with extensive pancreatic necrosis were firstly managed with either percutaneous drainage (PD group; n = 9) or open necrosectomy (ON group; n = 4). Debridement of necrotic tissue was subsequently performed via the drain tract by STE. ERCP was performed only when there was a suspicious of persistent pancreatic duct disruption or choledocholithiasis. RESULTS: In the PD group, the median number of STE sessions required was 3 (range 2-8). The median hospital and ICU stay were 84 days (range 29-163 days) and 0 day (range 0-64 days), respectively, with an overall success rate of 67%. In the ON group, the median number of STE sessions required was 6.5 (range 1-18). The median hospital and ICU stay were 82 days (range 58-194 days) and 19 days (range 4-24 days), respectively. No mortality or failure was noted in the latter group. ERCP was required in nine of 13 patients. CONCLUSION: Combined ERCP and STE is a useful adjunct in treating pancreatic necrosis or abscess.

Abscess↗
PubMed2004

Constitutional activation of IL-6-mediated JAK/STAT pathway through hypermethylation of SOCS-1 in human gastric cancer cell line.

The interleukin-mediated Janus kinase (JAK)/STAT pathway plays a crucial role in carcinogenesis. Recently, increased STAT3 activity was found in hepatocellular carcinoma and multiple myeloma in which there was silencing of SOCS-1 (suppressor of cytokine signalling-1) by gene promoter hypermethylation. We investigated the expression level of interleukin-6 (IL-6) and SOCS-1 in gastric cancer cell lines. Expression of SOCS-1 correlated with IL-6 level in most of the cell lines, except for AGS cells in which SOCS-1 was absent despite a high level of IL-6 production. Methylation analysis by methylation-specific polymerase chain reaction and bisulphite sequencing revealed that CpG island of SOCS-1 was densely methylated in AGS cells. Demethylation treatment by 5'aza-deoxycytidine restored SOCS-1 expression and also suppressed constitutive STAT3 phosphorylation in AGS cells. Moreover, methylation of SOCS-1 was detected in 27.5% (11 of 40) of primary gastric tumours samples, 10% (one of 10) of adjacent noncancer tissues but not in any (zero of nine) normal gastric mucosa. Methylation of SOCS-1 also correlated with the loss of mRNA expression in some primary gastric cancers. In conclusion, this is the first report to demonstrate that hypermethylation of SOCS-1 led to gene silencing in gastric cancer cell line and primary tumour samples. Downregulation of SOCS-1 cooperates with IL-6 in the activation of JAK/STAT pathway in gastric cancer.

Carrier Proteins↗
PubMed2004

Can visual distraction decrease the dose of patient-controlled sedation required during colonoscopy? A prospective randomized controlled trial.

BACKGROUND AND STUDY AIMS: We previously demonstrated that audio distraction using relaxation music could lead to a decrease in the dose of sedative medication required and improve patient satisfaction during colonoscopy. This prospective randomized controlled trial was designed to test the hypotheses that visual distraction may also decrease the requirement for sedatives and that audio and visual distraction may have additive beneficial effects when used in combination. PATIENTS AND METHODS: 165 consecutive patients who underwent elective colonoscopy were randomly allocated into three groups to receive different modes of sedation: group 1 received visual distraction and patient-controlled sedation (PCS); group 2 received audiovisual distraction and PCS; group 3 received PCS alone. A mixture of propofol and alfentanil, delivered by a Graseby 3300 PCA pump, was used for PCS in these groups. Each bolus of PCS delivered 4.8 mg propofol and 12 micro g alfentanil. Measured outcomes included the dose of PCS used, complications, recovery time, pain score, satisfaction score, and willingness to use the same mode of sedation if the procedure were to be repeated. RESULTS: Eight patients were excluded after randomization. The mean+/-SD dose of propofol used in group 2 (0.81 mg/kg +/- 0.49) was significantly less than the dose used in group 1 (1.17 mg/kg +/- 0.81) and that used in group 3 (1.18 mg/kg +/- 0.60) ( P < 0.01, one-way analysis of variance). The mean +/- SD pain score was also lower in group 2 (5.1 +/- 2.5), compared with the pain scores in group 1 (6.2 +/- 2.2) and group 3 (7.0 +/- 2.4) ( P < 0.01, one-way analysis of variance). The mean +/- SD satisfaction score was higher in groups 1 (8.2 +/- 2.4)) and 2 (8.4 +/- 2.4), compared with the score in group 3 (6.1 +/- 2.9) ( P < 0.01, one-way analysis of variance). A majority of patients in groups 1 (73 %) and 2 (85 %) said that they would be willing to use the same mode of sedation again, compared with only 53 % in group 3 ( P < 0.01, chi-squared test). CONCLUSIONS: Visual distraction alone did not decrease the dose of sedative medication required for colonoscopy. When audio distraction was added, both the dose of sedative medication required and the pain score decreased significantly. Both visual and audiovisual distraction might improve patients' acceptance of colonoscopy.

Acoustic Stimulation↗
PubMed2004

Short-term and long-term results of endoscopic balloon dilation for achalasia: 12 years' experience.

BACKGROUND AND STUDY AIMS: This retrospective study reports 12 years' experience with pneumatic dilation treatment in patients with achalasia and attempts to define factors capable of predicting failure of endoscopic dilation. PATIENTS AND METHODS: Consecutive patients with achalasia who received endoscopic balloon dilation were studied retrospectively. Repeat dilation was carried out if dysphagia persisted or recurred. A structured symptom score questionnaire (the Eckardt score) was conducted by phone with patients who had received dilation and had been followed up for more than 2 years. Failure was defined as the presence of significant dysphagic symptoms after more than two repeat dilations. Data for the first 2 years (short-term) and for the subsequent follow-up (long-term) were analyzed. RESULTS: From 1989 to 2001, 66 patients underwent endoscopic balloon dilation for achalasia; three perforations (4.5 %) occurred, with no mortalities. Dysphagic symptoms significantly improved 12 weeks after the procedure ( P < 0.05). Fourteen patients (20 %) required a second dilation procedure within a median of 7 months (range 1 - 52 months), and 13 of them underwent repeat dilations within the first 2 years. Five patients (7.5 %) required further surgical or endoscopic therapy. Fifty-eight patients received pneumatic dilation for more than 2 years; 32 (55 %) responded to the questionnaire. The mean dysphagia score was 1.7 (SD 1.2), with only five patients (16 %) having significant dysphagic symptoms during a median follow-up period of 55 months (range 26 - 130 months). The cumulative success rates for pneumatic dilation after 5 and 19 years were 74 % and 62 %, respectively. Cox regression analysis identified small balloon size (30 mm) as the only significant factor capable of predicting failure of endoscopic dilation ( P = 0.009; relative risk 5.3; 95 % confidence interval, 1.7 to 40.9). CONCLUSIONS: Endoscopic balloon dilation is an effective treatment for achalasia, with minimal morbidity (60 % experience long-term benefit).

Adolescent↗
PubMed2004

Factors predicting progression of gastric intestinal metaplasia: results of a randomised trial on Helicobacter pylori eradication.

BACKGROUND AND AIMS: Gastric intestinal metaplasia (IM) is generally considered to be a precancerous lesion in the gastric carcinogenesis cascade. This study identified the risk factors associated with progression of IM in a randomised control study. SUBJECTS AND METHODS: A total of 587 Helicobacter pylori infected subjects were randomised to receive a one week course of anti-Helicobacter therapy (omeprazole, amoxicillin, and clarithromycin (OAC)) or placebo. Subjects underwent endoscopy with biopsy at baseline and at five years. Severity of IM was graded according to the updated Sydney classification and progression was defined as worsening of IM scores at five years in either the antrum or corpus, or development of neoplasia. Backward stepwise multiple logistic regression was used to identify independent risk factors associated with IM progression. RESULTS: Of 435 subjects (220 in the OAC and 215 in the placebo group) available for analysis, 10 developed gastric cancer and three had dysplasia. Overall progression of IM was noted in 52.9% of subjects. Univariate analysis showed that persistent H pylori infection, age >45 years, male subjects, alcohol use, and drinking water from a well were significantly associated with IM progression. Duodenal ulcer and OAC treatment were associated with a reduced risk of histological progression. Progression of IM was more frequent in those with more extensive and more severe IM at baseline. With multiple logistic regression, duodenal ulcer (odds ratio (OR) 0.23 (95% confidence interval (CI) 0.09-0.58)) was found to be an independent protective factor against IM progression. Conversely, persistent H pylori infection (OR 2.13 (95% CI 1.41-3.24)), age >45 years (OR 1.92 (95% CI 1.18-3.11)), alcohol use (OR 1.67 (95% CI 1.07-2.62)), and drinking water from a well (OR 1.74 (95% CI 1.13-2.67)) were independent risk factors associated with IM progression. CONCLUSION: Eradication of H pylori is protective against progression of premalignant gastric lesions.

Aged↗
PubMed2003

Minimal invasive approach of gastric and esophageal mobilization in total pharyngolaryngoesophagectomy: total laparoscopic and hand-assisted laparoscopic technique.

BACKGROUND: To evaluate early results in total pharyngolaryngoesophagectomy (PLE) by minimally invasive approaches for patients suffered from pharyngoesophageal tumor. METHODS: Between April 1998 and September 2001, 12 consecutive patients underwent either total laparoscopic (n = 9) or hand-assisted laparoscopic (n = 3) gastric mobilization plus transhiatal esophageal resection in total PLE. The operative data and postoperative outcomes were evaluated. RESULTS: Total PLE by minimally invasive approach was successfully performed in 11 patients, and 1 patient required conversion due to uncontrolled bleeding. The median total operative time was 8.5 h (range, 5-11 h) and the abdominal laparoscopic stage usually took less than 4 h. The median time for extubation was 2 days (range, 1-4 days) and the median ICU stay was 2 days (range, 1-20 days). There was no 30-day mortality, and major complications occurred in 5 patients (42%). CONCLUSION: Minimally invasive PLE is a feasible and safe alternative to conventional open surgery for patients with pharyngoesophageal carcinoma.

Adult↗
PubMed2003

Through-the-scope stent for malignant gastric outlet obstruction.

This report is of the technique and results for through-the-scope stent in palliating malignant gastric outlet obstruction for 17 patients. All procedures were done using conscious sedation and fluoroscopy. Enteral Wallstents with a diameter of 20 mm or 22 mm and length 60 mm or 90 mm were used and delivered over a guidewire through an endoscope with an operating channel of at least 3.7 mm. A total of 18 stents were placed. One stent failed to be deployed. One stent migrated and required insertion of a second stent. One patient required repeat endoscopy to stop bleeding from the tumour. Through-the-scope stent relieved obstructive symptoms for 14 (82%) patients. The median dysphagia score improved from 4 to 2 after through-the-scope stent (P=0.001). The median overall survival and hospital-free survival time was 6 weeks (interquartile range, 3-9 weeks) and 4 weeks (interquartile range, 1-7 weeks), respectively. To conclude, through-the-scope stent was safe and feasible, offering an alternative minimal invasive method to palliate obstructive symptoms for patients with inoperable tumours causing gastric outlet obstruction.

Aged↗
PubMed2002

Increased expression of survivin in gastric cancer patients and in first degree relatives.

Survivin was recently described as an apoptosis inhibitor. Its pathogenic role in gastric cancer is largely unknown. Expression of survivin in gastric cancer and non-cancer first-degree relatives, and its association with apoptosis and cyclo-oxygenase-2 expression was investigated. Fifty gastric cancer, 30 non-cancer first-degree relatives, 20 normal controls and five gastric cancer cell lines were studied. Survivin and cyclo-oxygenase-2 were evaluated by reverse transcriptase-polymerase chain reaction, immunohistochemistry and Western blot. Survivin expression was absent from normal gastric mucosa. All five cancer cell lines and 34 out of 50 (68%) human gastric cancer tissues expressed survivin mRNA. Survivin expression was less frequent (22%; P<0.001) in adjacent non-tumour gastric tissues. Immunohistochemistry and Western blot obtained similar findings. Gastric cancers with survivin expression displayed significantly reduced apoptosis (P=0.02), and associated with cyclo-oxygenase-2 overexpression at both mRNA (P=0.001) and protein levels (P=0.041). Moreover, survivin mRNA was detected in the gastric mucosa of eight (27%) non-cancer relatives. Expression in non-cancer patients showed positive correlation with H. pylori infection (P=0.004). This demonstrates the frequent expression of survivin in gastric cancer and in first-degree relatives. Co-expression of survivin and cyclo-oxygenase-2 may suggest multiple pathways contributing to the inhibition of apoptosis in gastric cancer.

Adult↗
PubMed2002

The clinical efficacy of neoadjuvant chemotherapy in squamous esophageal cancer: a prospective nonrandomized study of pulse and continuous-infusion regimens with Cisplatin and 5-Fluorouracil.

BACKGROUND: We evaluated cisplatin and 5-fluorouracil as preoperative adjuvant chemotherapy for patients with locally advanced squamous esophageal cancer and compared two different infusion regimens. The outcomes were also compared with those of our historical control patients treated by surgery alone. METHODS: From 1991 to 1997, 83 consecutive esophageal cancer patients underwent surgical exploration after completion of two cycles of cisplatin and 5-fluorouracil chemotherapy regimens, either in pulse or in continuous infusion cycles. Outcomes were compared with those of 76 historical control patients. Both groups were comparable in demographic characteristics and tumor stages. The resection rates, operative morbidity, mortality, and survival rates were compared. RESULTS: Partial response was achieved in 50% of patients who received chemotherapy. There was no chemotherapy-related mortality. The resection, morbidity, and mortality rates and median survival between the surgery-alone group and the chemotherapy group were 71.1% vs. 82%, 51% vs. 55%, and 4% vs. 10.8%, 12.0 vs. 13.5 months, respectively (P >.05). There was also no statistically significant difference between the two regimens. CONCLUSIONS: Preoperative adjuvant chemotherapy with cisplatin and 5-fluorouracil infusion, in pulse or continuous regimens, followed by surgery for squamous esophageal cancer patients had no added benefit in the overall survival.

Adult↗
PubMed2002

Prediction of therapeutic failure after adrenaline injection plus heater probe treatment in patients with bleeding peptic ulcer.

BACKGROUND: Continued or recurrent bleeding after endoscopic treatment for bleeding ulcer is a major adverse prognostic factor. Identification of such ulcers may allow for alternate treatments. AIM: To determine factors predicting treatment failure with combined adrenaline injection and heater probe thermocoagulation. METHODS: Consecutive patients with bleeding peptic ulcers who received endoscopic therapy between January 1995 and March 1998 were studied. Data on clinical presentation, endoscopic findings, and treatment outcomes were collected prospectively. Multiple logistic regression analysis was used to identify independent risk factors for treatment failure. RESULTS: During the study period, 3386 patients were admitted with bleeding peptic ulcers: 1144 (796 men, 348 women) with a mean age of 62.5 (SD 17.6) years required endoscopic treatment. There were 666 duodenal ulcers (58.2%), 425 gastric ulcers (37.2%), and 53 anastomotic ulcers (4.6%). Initial haemostasis was successful in 1128 patients (98.6%). Among them, 94 (8.2%) rebled in a median time of 48 hours (range 3-480). Overall failure rate was 9.6%. Mortality rate was 5% (57/1144). Multiple logistic regression analysis revealed that hypotension (odds ratio (OR) 2.21, 95% confidence interval (CI) 1.40-3.48), haemoglobin level less that 10 g/dl (OR 1.87, 95% CI 1.18-2.96), fresh blood in the stomach (OR 2.15, 95% CI 1.40-3.31), ulcer with active bleeding (OR 1.65, 95% CI 1.07-2.56), and large ulcers (OR 1.80, 95% CI 1.15-2.83) were independent factors predicting rebleeding. CONCLUSIONS: Larger ulcers with severe bleeding at presentation predict failure of endoscopic therapy.

Adult↗
PubMed2002

Relationship between Helicobacter pylori babA2 status with gastric epithelial cell turnover and premalignant gastric lesions.

BACKGROUND: Helicobacter pylori blood group antigen binding adhesin (BabA) mediates bacterial adherence to human blood group antigens on gastric epithelium. Although strains harbouring babA2 were recently found to be associated with peptic ulcer and gastric cancer, the role of babA2 in cellular turnover, severity of gastritis, and premalignant changes is poorly understood. AIM: We correlated H pylori babA2, vacuolating toxin (vacA), and cytotoxin associated gene A (cagA) genotypes with the severity of gastric inflammation and epithelial cell turnover in a group of Chinese patients from an area with a high incidence of gastric cancer. PATIENTS AND METHODS: H pylori isolates were obtained from 104 Chinese patients who participated in a gastric cancer prevention programme. Genotype variants of babA2, vacA, and cagA were determined by polymerase chain reaction. Antrum and corpus histopathology was examined according to the updated Sydney classification. Apoptosis was scored by terminal uridine deoxynucleotidyl nick end labeling (TUNEL) and proliferation by Ki-67 immunostaining. RESULTS: Of the 104 patients, 102 (98.1%) harboured cagA(+) strains and all had vacA s1 genotype. The babA2(+) strains were found in 83 (79.8%) patients and were associated with higher lymphocytic infiltration (p=0.028), presence of glandular atrophy (odds ratio (OR) 7.5, 95% confidence interval (CI) 2.3-24.3), and intestinal metaplasia (OR 7.4, 95% CI 2.2-25.3) in the antrum. Increased epithelial proliferation was also noted in individuals infected with babA2(+) strains (p=0.025). Strains harbouring cagA(+)/vacA s1 genotypes lacked this association in the absence of babA2. CONCLUSIONS: The presence of babA2(+) H pylori strains alone or in combination with cagA(+) and vacA s1 was associated with the presence of preneoplastic gastric lesions.

Adhesins, Bacterial↗