GASTRIC CANCERS IN SINGAPORE: POOR PROGNOSIS ARISING FROM LATE PRESENTATION

Background : Mortality rates from gastric cancer, apart from those derived from Japanese series, remain poor. This paper sought to determine the present outcome of gastric carcinoma in a predominantly Chinese population in Singapore. Prognostic factors useful in predicting survival were also evaluated in this population. Method : All cases of histologically confirmed gastric adenocarcinoma presenting in 1992 were entered into a prospective database. Prognostic factors related to age, sex, site of disease, depth of invasion, histological grade, nodal status and stage of disease were evaluated in patients with resectable disease to determine their utility in predicting survival. Results : Of 1310 consecutive patients with histologically proven adenocarcinomas, 37% had distant metastases at presentation predominantly in the liver (21%) and peritoneal cavity (20%). Sixty-four per cent of patients underwent surgery and in only 51% of these patients was resection of the turnour possible. Stages 111 and IV (T4N2) locally advanced disease were present in 38% of patients. Thus the majority of patients presented with late or metastatic disease (75%, stages 111 and IV). Sixty per cent of patients were alive at I year and 40% at 2 years after resection of the tumour (Kaplan-Meier survival plots). In contrast, no patient survived longer than a year if the tumour was not resectable (P < 0.001, log-rank test). Median survival of patients without surgery was 12 weeks. Median survival for patients with resected stage IV disease was 23 weeks, compared to 18 weeks after surgical bypass. Age, sex, site, depth of invasion and histological grade did not significantly predict survival. Patients with node-negative disease survived longer (2 year, 70%) than those with nodal involvement (2 years, 44%; P = 0.06, log-rank test). Pathologic staging with the TNM system was useful in predicting survival (P < 0.001). Sixty per cent of patients with stage I and II disease were alive at 2 years compared to 54% with stage III disease and 0% with stage IV disease. Conclusion : The prognosis of stomach cancer remains poor, due predominantly to late presentation. Pathologic TNM staging and nodal status were useful in predicting survival outcome after resection. If the tumour were resectable, survival was appreciable even in patients with advanced stage III (2 years, 54%) and stage IV (1 year, 40%) disease. Strategies to improve outcome should focus on early detection of gastric carcinomas.     

Whole body 18FDG-PET and the response of esophageal cancer to induction therapy: results of a prospective trial.

PURPOSE: Whole-body 18F-fluorodeoxyglucose ([18F]FDG) positron emission tomography (PET) imaging before and after induction therapy was prospectively evaluated in patients with esophageal cancer to determine whether changes in PET images could measure response to therapy. PATIENTS AND METHODS: Between April 1997 and April 1999, 39 patients (34 men and five women; median age, 59 years; range, 36 to 76 years) with esophageal cancer were prospectively enrolled in a single-institution clinical trial of staging, including PET, induction therapy, restaging including PET, and esophagectomy. All patients undergoing esophagectomy after induction therapy (n = 17) were followed either to recurrence, to death, or through a disease-free interval of at least 24 months. RESULTS: PET after standard staging studies and before therapy imaged undetected sites of metastatic disease in six patients (15%). Restaging (including PET) after induction therapy did not identify any patients with disease progression or any patients with loco-regionally unresectable disease at exploration. The median decrease in the standardized uptake value (SUV) during induction therapy was 59%. After R0 esophagectomy, the 2-year disease-free and overall survival was 38% and 63%, respectively, among patients who had a less than 60% decrease in SUV, and 67% and 89%, respectively, among patients who had a greater than 60% decrease in SUV (P =.055 and P =.088, respectively). CONCLUSION: Compared with conventional imaging, PET detects additional sites of metastatic disease at initial evaluation. After induction therapy, PET did not add to the estimation of loco-regional resectability and did not detect new distant metastases. However, changes in [18F]FDG PET may predict disease-free and overall survival after induction therapy and resection in patients with esophageal cancer. Further evaluation in larger trials is warranted.     

Biological evaluation of intervertebral disc cells in different formulations of gellan gum‐based hydrogels

Gellan gum (GG)‐based hydrogels are advantageous in tissue engineering not only due to their ability to retain large quantities of water and provide a similar environment to that of natural extracellular matrix (ECM), but also because they can gelify in situ in seconds. Their mechanical properties can be fine‐tuned to mimic natural tissues such as the nucleus pulposus (NP). This study produced different formulations of GG hydrogels by mixing varying amounts of methacrylated (GG‐MA) and high‐acyl gellan gums (HA‐GG) for applications as acellular and cellular NP substitutes. The hydrogels were physicochemically characterized by dynamic mechanical analysis. Degradation and swelling abilities were assessed by soaking in a phosphate buffered saline solution for up to 170 h. Results showed that as HA‐GG content increased, the modulus of the hydrogels decreased. Moreover, increases in HA‐GG content induced greater weight loss in the GG‐MA/HA‐GG formulation compared to GG‐MA hydrogel. Potential cytotoxicity of the hydrogel was assessed by culturing rabbit NP cells up to 7 days. An MTS assay was performed by seeding rabbit NP cells onto the surface of 3D hydrogel disc formulations. Viability of rabbit NP cells encapsulated within the different hydrogel formulations was also evaluated by Calcein‐AM and ATP assays. Results showed that tunable GG‐MA/HA‐GG hydrogels were non‐cytotoxic and supported viability of rabbit NP cells. Copyright © 2012 John Wiley & Sons, Ltd.     

Self-reported hypoglycaemia in insulin-treated patients with diabetes mellitus: results from the Singapore cohort of the International Operations Hypoglycaemia Assessment Tool study

INTRODUCTIONHypoglycaemia constitutes a significant barrier to achieving glycaemic control with insulin in both Type 1 (T1DM) and Type 2 diabetes mellitus (T2DM). The International Operations Hypoglycaemia Assessment Tool (IO HAT) study was designed to determine the incidence of hypoglycaemia in insulin-treated patients with T1DM and T2DM.METHODSThe IO HAT study retrospectively and prospectively assessed the incidence of hypoglycaemia in patients with insulin-treated diabetes mellitus in nine countries. This sub-analysis included patients from Singapore with T1DM or T2DM who were aged ≥ 21 years and had completed two self-assessment questionnaires (SAQ1 and SAQ2).RESULTSOf the 50 T1DM and 320 T2DM patients who completed the SAQ1, 39 T1DM and 265 T2DM patients completed SAQ2; 100% and 90.9%, respectively, experienced at least one hypoglycaemic event prospectively. The incidence rates of any hypoglycaemia were 49.5 events per patient-year (EPPY) and 16.1 EPPY for T1DM and T2DM patients, respectively, in the four-week prospective period. Hypoglycaemia rate did not differ in terms of glycated haemoglobin level. The vast majority of T1DM or T2DM patients (92.0% and 90.7%, respectively) knew the overall definition of hypoglycaemia before study participation, although over half of the patients (T1DM 54.0%, T2DM 51.9%) defined hypoglycaemia based only on symptoms.CONCLUSIONHigh proportions of insulin-treated patients with diabetes mellitus in Singapore reported hypoglycaemic events prospectively, showing that they had underreported hypoglycaemic episodes retrospectively. Patient education can help in improving hypoglycaemia awareness and its management in the region.     

Diabetes and orthopaedic surgery: a review

Diabetes mellitus (DM) is common, estimated to affect 425 million people worldwide in 2017. It is a condition that is continually growing in prevalence and is often associated with multiple co-morbidities. Its multi-system effects on the body mean that its management can pose a challenge, even to more experienced clinicians. In orthopaedic practice, diabetic patients are commonly encountered owing to their increased fracture risk and complications of the disease such as diabetic foot. An appropriate knowledge of diabetes, its pathophysiology, immunology and the pharmacology of medications used in its treatment is essential, as the consequences of mismanagement can be grave. Optimal treatment of diabetics can often require the involvement of a wider multidisciplinary team. Complications that can be encountered in the perioperative and postoperative periods include, diabetic ketoacidosis, hyperosmolar hyperglycaemic state, surgical site infection and venous thromboembolism. This review outlines current concepts in the perioperative management of diabetes and its manifestations within orthopaedic surgery, with a focus on outcomes and complications. A review of the available literature reveals conflicting conclusions between studies, with no clear effect or consensus yet established for many issues. There is a need for a greater number of well-designed, high-quality, appropriately powered trials to establish the true effect of diabetes on outcomes in orthopaedic surgery.     

High Serum Levels of Vascular Endothelial Growth Factor-A and Transforming Growth Factor-β1 Before Neoadjuvant Chemoradiotherapy Predict Poor Outcomes in Patients with Esophageal Squamous Cell Carcinoma Receiving Combined Modality Therapy

Background and Purpose

This study was aimed at using proximity ligation assay (PLA) followed by enzyme-linked immunosorbent assay (ELISA) to identify serum biomarkers that predict treatment response and survival for patients with esophageal squamous cell carcinoma (ESCC) undergoing neoadjuvant concurrent chemoradiotherapy (CCRT) followed by esophagectomy.

Methods

Seventy-nine patients with ESCC receiving CCRT of taxane-based/5-fluorouracil-based chemotherapy and 40 Gy followed by surgery were enrolled. Serum samples were collected before and <1 month after CCRT. Fifteen biomarkers were analyzed using PLA. Biomarkers significantly correlating with pathological response/survival were verified by ELISA. Associations of the serum level of biomarkers and clinical factors with pathological response, disease-free survival (DFS), and overall survival (OS) were evaluated by analysis of variance and log-rank tests.

Results

Thirty patients had complete response (38 %), 37 had microscopic residual disease (47 %), and 12 had macroscopic residual disease (15 %). With a median follow-up of 52.8 months, the median DFS was 43 months. Among the 15 biomarkers screened by PLA, vascular endothelial growth factor (VEGF)-A and transforming growth factor (TGF)-β1 were significantly associated with pathological response and/or DFS. These biomarkers were further analyzed by ELISA to confirm initial biomarker findings by PLA. After ELISA of these two markers, only VEGF-A levels were significantly correlated with pathological response. On multivariate analysis, patients with combined high pre-CCRT VEGF-A and TGF-β1 levels (greater than or equal to the median), independent of pathological response, had significantly worse DFS (11 months vs. median not reached; p = 0.007) and OS (16 vs. 46 months; p = 0.07).

Conclusions

Pre-CCRT serum VEGF-A and TGF-β1 levels may be used to predict pathological response and survivals for ESCC patients receiving combined-modality therapy.     

Importance of catalase in the disposal of hydrogen peroxide within human erythrocytes

The catalase within normal, intact human erythrocytes was completely inactivated with amino triazole. The rate of 14CO2 evolution, when the cells were subsequently incubated with 14C-labeled glucose, provided a measure of the rate at which NADPH was being oxidized by the glutathione peroxidase/reductase system for the disposal of H2O2. This rate was determined in control cells and in catalase-inactivated cells while the cells were exposed to H2O2, which was generated at various constant and predetermined rates by glucose oxidase. The results indicated that catalase handles approximately half of the generated H2O2. The glutathione peroxidase/reductase mechanism accounted for the other half. These results are in agreement with our earlier findings on erythrocytes of a subject with a genetic deficiency of catalase. However, an unexpected result with the present approach was the finding that the increased dependence on the glutathione peroxidase/reductase mechanism did not occur until greater than 98% of the catalase had been inactivated. The latter observation indicates that catalase and the glutathione peroxidase/reductase system function intracellularly in a manner very different from that previously ascribed to them. An explanation of the findings requires that the two methods of H2O2 disposal function in a coordinated way, such as a sequential action in which the glutathione peroxidase/reductase system is the rate-limiting step.