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John Wong

Publications and source records attributed to John Wong.

At least 37 records · Page 2Linked to original sources
PubMed2006

Aberrant promoter hypermethylation and silencing of the critical 3p21 tumour suppressor gene, RASSF1A, in Chinese oesophageal squamous cell carcinoma.

3p21 is an important locus harbouring critical tumour suppressor genes (TSG), which are implicated in the pathogenesis of multiple tumours, including oesophageal carcinoma. RASSF1A is a 3p21.3 candidate TSG frequently inactivated by promoter methylation in multiple tumours. We investigated RASSF1A promoter methylation and gene expression in Chinese oesophageal squamous cell carcinoma (ESCC) to compare it to data from Japanese patients. Methylation-specific PCR (MSP) showed that RASSF1A was partially methylated in 3/7 (43%) cell lines; 22/64 (34%) primary tumours and 3/64 (5%) corresponding non-tumour samples; and was not methylated in 2 immortalized normal oesophageal epithelial cell lines and 6 normal oesophageal epithelium samples. Bisulfite genome sequencing confirmed the MSP results. Promoter hypermethylation correlated well with RASSF1A mRNA down-regulation. Treatment of cell lines with 5-aza-2'-deoxycytidine activated RASSF1A mRNA expression along with promoter demethylation. RASSF1A hypermethylation in the Chinese cohort was much lower than in a published report of Japanese ESCC patients (52%) and cell lines (74%). Our own analysis of Japanese ESCC cell lines for direct comparison also detected a high frequency of RASSF1A hypermethylation (8/10; 80%) and high levels of hypermethylation at each CpG site. No significant association between RASSF1A hypermethylation and histological differentiation (p=0.953), tumour staging (p=0.117), or survival (p=0.7571) was found in Chinese ESCC, unlike the results of Japanese patients. The incidence of oesophageal cancer shows marked variation by geographic area and ethnic group; it is almost three times higher in China than in Japan, indicating possible different pathogenetic mechanisms. Our results show that RASSF1A hypermethylation in ESCC has epidemiological/ethnic differences, and suggest that Chinese ESCC may result from different pathogenetic mechanisms.

Carcinoma, Squamous Cell↗
PubMed2005

Quality of life and cost-effectiveness of anti-HCV therapy in HIV-infected patients.

Quality of life studies in chronic hepatitis C using specific questionnaires have been performed in mono-infected patients; however, these studies have just begun in HIV-HCV co-infected patients. The questionnaires used in mono-infected patients are not well adapted for co-infected patients and need to be redesigned. Typically, co-infected patients have multiple symptoms that may be attributable to HIV, to HCV, to a combination of both diseases or even to side effects related to drug therapy. These patients usually need substitutive therapy to manage side effects related to HCV therapy, particularly anaemia, leukopenia and depression. There are no cost-effectiveness studies published on the current HCV standard therapy with pegylated interferon and ribavirin. However, there is some research on the old standard interferon and ribavirin, which shows that HCV therapy is cost-effective. Cost-effectiveness studies in co-infected patients will have to take into account variables that do not affect mono-infected patients, such as the different levels of CD4, the increase in the fibrosis progression rate and the use of other expensive drugs for the management of side effects. Currently, the literature does not provide adequate information on the effect of HCV infection on the quality of life of HIV-HCV co-infected patients or the most cost-effective HCV therapy.

Antiviral Agents↗
PubMed2005

A phase I/II trial to evaluate three-dimensional conformal radiation therapy confined to the region of the lumpectomy cavity for Stage I/II breast carcinoma: initial report of feasibility and reproducibility of Radiation Therapy Oncology Group (RTOG) Study 0319.

BACKGROUND: This prospective study (Radiation Therapy Oncology Group Study 0319) examines the use of three-dimensional conformal external beam radiation therapy to deliver accelerated partial breast irradiation. Reproducibility, as measured by technical feasibility, was the primary end point with the goal of demonstrating whether the technique is widely applicable in a multicenter setting before a Phase III trial is undertaken. METHODS AND MATERIALS: This study was designed such that if fewer than 5 cases out of the first 42 patients evaluable were scored as unacceptable, the treatment would be considered reproducible. Patients received 38.5 Gy in 3.85 Gy/fraction delivered twice daily. The clinical target volume included the lumpectomy cavity plus a 10-15-mm margin bounded by 5 mm within the skin surface and the lung-chest wall interface. The planning target volume (PTV) included the clinical target volume plus a 10-mm margin. Treatment plans were judged as follows: (1) No variations (total coverage), 95% isodose surface covers 100% of the PTV and all specified critical normal tissue dose-volume histogram (DVH) limits met. (2) Minor variation (marginal coverage), 95% isodose surface covers between > or = 95% and <100% of the PTV. No portion of PTV receives <93% of prescription (isocenter) dose. All specified critical normal tissue DVH limits fall within 5% of the guidelines. (3) Major variation (miss), 95% isodose surface covers <95% of the PTV. Portion of PTV receives <93% of prescription isocenter dose. Any critical normal tissue DVH limit exceeds 5% of the specified value. RESULTS: A total of 58 patients were enrolled on this study between 8/15/03 and 4/30/04, 5 of whom were ineligible or did not receive protocol treatment. Two additional patients were excluded, one because the on-study form was not submitted, and the other because no treatment planning material was submitted. This primary end point analysis is based on the first 42 (out of 51) evaluable patients, which were accrued from 17 different institutions (31 centers were credentialed for case enrollment, but because of rapid accrual, not all centers were able to submit cases before trial closure). These 42 patients had the following characteristics: median age was 61 years; 48% had a maximum tumor dimension of <1 cm; 86% had invasive ductal carcinoma; 64% were postmenopausal; the location of tumor was upper outer for 40% and upper central for 21%; 79% had no chemotherapy, and 64% had no hormonal therapy. There were 4 cases with major variations (all 4 related to normal tissue DVHs exceeding 5% of the specified limit). A total of 32 cases with minor variations in treatment plans were detected (16 related to normal tissue DVHs exceeding the specified limits [by < or = 5%], 6 related to suboptimal coverage of the PTV, and 10 related to both). There were 6 cases with no variations. Of the 51 total evaluable patients, 1 additional major variation was noted (PTV receiving <93% of the prescription dose). An additional 5 cases with minor variations in treatment plans were detected (3 related to normal tissue DVHs exceeding the specified limits [by < or = 5%], 1 related to suboptimal coverage of the PTV, and 1 related to both). There were 3 more cases with no variations. CONCLUSION: Accelerated partial breast irradiation using three-dimensional conformal external beam radiation therapy was shown in this preliminary analysis of the first 42 evaluable patients to be technically feasible and reproducible in a multi-institutional trial using exceptionally strict dosimetric criteria.

Adult↗
PubMed2005

Hepatocyte growth factor promotes cancer cell migration and angiogenic factors expression: a prognostic marker of human esophageal squamous cell carcinomas.

PURPOSE: Hepatocyte growth factor/scatter factor (HGF/SF) and its receptor, c-Met, play important roles in tumor development and progression. In this study, we measured the serum HGF levels in patients with esophageal squamous cell carcinoma (ESCC) to evaluate its relationships with clinicopathologic features and the role of HGF in ESCC. EXPERIMENTAL DESIGN: One hundred and forty-nine patients with ESCC were studied. Pretherapy serum was collected and ELISA was used to detect the concentrations of HGF, vascular endothelial growth factor (VEGF), and interleukin 8 (IL-8). The function of HGF was shown by invasion chamber assay. RESULTS: Pretherapy serum HGF was found to be significantly higher in patients with ESCC than in control subjects. The levels of HGF correlated significantly with advanced tumor metastasis stage and survival. Multivariate analyses showed that serum HGF level in cell migration was an independent prognostic factor. Increased HGF serum levels correlated positively with serum levels of VEGF and IL-8. Our results also showed that HGF was overexpressed in ESCC tissues and cell lines. In vitro study showed that HGF could stimulate ESCC cell to express VEGF and IL-8 and markedly enhance invasion and migration of ESCC cells. Furthermore, HGF-induced IL-8 and VEGF expression was dependent on extracellular signal-regulated kinase signaling pathways. The inhibition of extracellular signal-regulated kinase activation reduced HGF-mediated IL-8 and VEGF expression. CONCLUSIONS: Our results suggest that serum HGF may be a useful biomarker of tumor progression and a valuable independent prognostic factor in patients with ESCC. HGF may be involved in the progression of ESCC as an autocrine/paracrine factor via enhancing angiogenesis and tumor cell invasion and migration.

Aged↗
PubMed2005

Reactivation of latent granulomatous infections by infliximab.

Although infliximab and etanercept share tumor necrosis factor (TNF) as a common therapeutic target, accumulating data indicate that infliximab (an anti-TNF monoclonal antibody) poses a greater risk of reactivation of latent granulomatous infections than does etanercept (a soluble TNF receptor). Similarly, infliximab is effective for the treatment of chronic granulomatous inflammatory conditions (e.g., Crohn disease) for which etanercept is ineffective. The ability of infliximab to disrupt established granulomas may be distinct from its ability to neutralize soluble TNF. Further research to elucidate the mechanism of the antigranuloma activity of infliximab is warranted.

Antibodies, Monoclonal↗
PubMed2005

Assessment of residual error for online cone-beam CT-guided treatment of prostate cancer patients.

PURPOSE: Kilovoltage cone-beam CT (CBCT) implemented on board a medical accelerator is available for image-guidance applications in our clinic. The objective of this work was to assess the magnitude and stability of the residual setup error associated with CBCT online-guided prostate cancer patient setup. Residual error pertains to the uncertainty in image registration, the limited mechanical accuracy, and the intrafraction motion during imaging and treatment. METHODS AND MATERIALS: The residual error for CBCT online-guided correction was first determined in a phantom study. After online correction, the phantom residual error was determined by comparing megavoltage portal images acquired every 90 degrees to the corresponding digitally reconstructed radiographs. In the clinical study, 8 prostate cancer patients were implanted with three radiopaque markers made of high-winding coils. After positioning the patient using the skin marks, a CBCT scan was acquired and the setup error determined by fusing the coils on the CBCT and planning CT scans. The patient setup was then corrected by moving the couch accordingly. A second CBCT scan was acquired immediately after the correction to evaluate the residual target setup error. Intrafraction motion was evaluated by tracking the coils and the bony landmarks on kilovoltage radiographs acquired every 30 s between the two CBCT scans. Corrections based on soft-tissue registration were evaluated offline by aligning the prostate contours defined on both planning CT and CBCT images. RESULTS: For ideal rigid phantoms, CBCT image-guided treatment can usually achieve setup accuracy of 1 mm or better. For the patients, after CBCT correction, the target setup error was reduced in almost all cases and was generally within +/-1.5 mm. The image guidance process took 23-35 min, dictated by the computer speed and network configuration. The contribution of the intrafraction motion to the residual setup error was small, with a standard deviation of +/-0.9 mm. The average difference between the setup corrections obtained with coil and soft-tissue registration was greatest in the superoinferior direction and was equal to -1.1 +/- 2.9 mm. CONCLUSION: On the basis of the residual setup error measurements, the margin required after online CBCT correction for the patients enrolled in this study would be approximatively 3 mm and is considered to be a lower limit owing to the small intrafraction motion observed. The discrepancy between setup corrections derived from registration using coils or soft tissue can be due in part to the lack of complete three-dimensional information with the coils or to the difficulty in prostate delineation and requires further study.

Algorithms↗
PubMed2005

MRI-based volumetric assessment of cardiac anatomy and dose reduction via active breathing control during irradiation for left-sided breast cancer.

PURPOSE: Heart dose-volume analysis using computed tomography (CT) is limited because of motion artifact and poor delineation between myocardium and ventricular space. We used dedicated cardiac magnetic resonance imaging (MRI) to quantify exclusion of left ventricular (LV) myocardium via active breathing control (ABC) during left breast irradiation and to determine the correlation between irradiated whole heart and LV volumes. METHODS AND MATERIALS: Fifteen patients who completed adjuvant irradiation for early-stage left breast cancer participated. Treatment consisted of 45 Gy to the entire breast using ABC followed by a 16-Gy electron boost to the lumpectomy cavity. Patients underwent planning CT scans in free breathing (FB) and moderate deep inspiration breath hold (mDIBH). Electrocardiogram-gated cardiac MRI was performed in the treatment position using alpha-cradle immobilization. MRI scans were acquired in late diastole (LD), mid-diastole (MD), and systole (S) for both FB and mDIBH. After image fusion with the patients' radiation therapy planning CT scan, MRI LV volumes were defined for the three examined phases of the cardiac cycle, and comparative dose-volume analysis was performed. RESULTS: Cardiac volume definition was found to differ significantly because of combinations of respiratory and intrinsic heart motion. The fraction of LV myocardium receiving 50% (22.5 Gy) of the prescribed whole breast dose (V(22.5)) was reduced by 85.3%, 91.8%, and 94.6% via ABC for LD, MD, and S, respectively. Linear regression revealed strong correlation between MRI-defined whole heart and LV V(22.5) reduction via ABC, suggesting that LV myocardium accounts for up to approximately 50% of the excluded heart volume through this technique. Significant but weaker correlations were noted between CT-defined whole heart and LV V(22.5) reductions with marked variability in the measurements of patients with larger amounts of heart in the treatment field. CONCLUSIONS: Cardiac MRI demonstrated a significant reduction in LV myocardium irradiated with the use of ABC. The correlation between reduction in V(22.5) values for LV wall and CT-defined whole heart suggests that CT is adequate for determining which patients are likely to benefit from ABC treatment, but inaccuracies inherent to standard CT dictate that more detailed imaging studies such as MRI are required for accurate cardiotoxicity assessment.

Breast Neoplasms↗
PubMed2005

Accuracy of a wireless localization system for radiotherapy.

PURPOSE: A system has been developed for patient positioning based on real-time localization of implanted electromagnetic transponders (beacons). This study demonstrated the accuracy of the system before clinical trials. METHODS AND MATERIALS: We describe the overall system. The localization component consists of beacons and a source array. A rigid phantom was constructed to place the beacons at known offsets from a localization array. Tests were performed at distances of 80 and 270 mm from the array and at positions in the array plane of up to 8 cm offset. Tests were performed in air and saline to assess the effect of tissue conductivity and with multiple transponders to evaluate crosstalk. Tracking was tested using a dynamic phantom creating a circular path at varying speeds. RESULTS: Submillimeter accuracy was maintained throughout all experiments. Precision was greater proximal to the source plane (sigmax = 0.006 mm, sigmay = 0.01 mm, sigmaz = 0.006 mm), but continued to be submillimeter at the end of the designed tracking range at 270 mm from the array (sigmax = 0.27 mm, sigmay = 0.36 mm, sigmaz = 0.48 mm). The introduction of saline and the use of multiple beacons did not affect accuracy. Submillimeter accuracy was maintained using the dynamic phantom at speeds of up to 3 cm/s. CONCLUSION: This system has demonstrated the accuracy needed for localization and monitoring of position during treatment.

Electrodes, Implanted↗
PubMed2005

A dose-escalation trial with the adaptive radiotherapy process as a delivery system in localized prostate cancer: analysis of chronic toxicity.

PURPOSE: To evaluate the validity of the chosen adaptive radiotherapy (ART) dose-volume constraints while testing the hypothesis that toxicity would not be greater at higher tumor dose levels. MATERIALS AND METHODS: In the ART dose escalation/selection trial, treatment was initiated with a generic planning target volume (PTV) formed as a 1-cm expansion of the clinical target volume (CTV). After the first week of therapy, the patient was replanned with a patient-specific PTV, constructed with CT and electronic portal images obtained in the first 4 days of treatment. A new multileaf collimator beam aperture was used. A minimum dose prescribed to the patient-specific PTV, ranging 70.2-79.2 Gy, was determined on the basis of the following rectal and bladder constraints: <5% of the rectal wall has a dose >82 Gy, <30% of the rectal wall has a dose >75.6 Gy, <50% of the bladder volume has a dose >75.6 Gy, and the maximum bladder dose is 85 Gy. A conformal four-field and/or intensity-modulated radiotherapy (IMRT) technique was used. Independent reviewers scored toxicities. The worst toxicity score seen was used as per the Common Toxicity Criteria grade scale (version 2). We divided the patients into three separate groups: 70.2-72 Gy, >72-75.6 Gy, and >75.6-79.2 Gy. Toxicities in each group were quantified and compared by the Pearson chi-squared test to validate our dose escalation/selection model. Grades 0, 1, 2, and 3 were censored as none vs. each category and none vs. any. RESULTS: We analyzed patients with follow-up greater than 1 year. The mean duration of follow-up was 29 months (range, 12-46 months). We report on 280 patients, mean age 72 years (range, 51-87 years). Only 60 patients received adjuvant hormones. Mean pretreatment prostate-specific antigen level was 9.3 ng/mL (range, 0.6-120 ng/mL). Mean Gleason score was 6 (range, 3-9). The lowest dose level was given to 49 patients, the intermediate dose to 131 patients, and 100 patients received the highest dose escalation. One hundred eighty-one patients (65%) were treated to a prostate field only and 99 patients (35%) to prostate and seminal vesicles. Chronic genitourinary and/or gastrointestinal categories were incontinence, persistent urinary retention, increased urinary frequency/urgency, urethral stricture, hematuria, diarrhea, rectal pain, bleeding, ulcer, fistula, incontinence, and proctitis. Toxicity at the high dose level was not different from toxicity at the intermediate or lower dose levels. No significant difference was observed in any of the individual toxicity categories. CONCLUSIONS: By applying the ART process--namely, developing a patient-specific PTV--to prostate cancer patients, significant dose escalation can be achieved without increases in genitourinary or gastrointestinal toxicity. Our data validate the rectal and bladder dose-volume constraints chosen for our three-dimensional conformal and IMRT prostrate radiotherapy planning.

Aged↗
PubMed2005

A single-layer, continuous, hand-sewn method for esophageal anastomosis: prospective evaluation in 218 patients.

HYPOTHESIS: A 1-layer, continuous technique for esophageal anastomosis after esophagectomy has been in routine use at the University of Hong Kong Medical Centre since 1996. This study aims to document the results of this method and examine factors that may predispose patients to complications associated with esophageal anastomosis. DESIGN: Retrospective study. SETTING: University academic surgical center. PATIENTS AND METHODS: We studied 218 consecutive patients who had an esophageal anastomosis constructed with a 1-layer, continuous technique. Data were prospectively collected. MAIN OUTCOME MEASURES: Morbidity and mortality rates, anastomotic leaks, stricture, and recurrences. RESULTS: Anastomotic leaks affected 7 patients (3.2%), of whom 3 required surgical reexploration and none died. The hospital mortality rate was 0.9% (2 patients), attributed to myocardial infarction and malignancy. Anastomotic strictures developed in 24 patients (11.1%). Multivariate analysis in those with gastric conduits showed that a cervical anastomosis (intrathoracic vs cervical; odds ratio, 0.27; 95% confidence interval, 0.08-0.87; P = .03) and use of the distal stomach (distal stomach vs whole stomach; odds ratio, 5.25; 95% confidence interval, 1.65-16.66; P = .005) were predictive of benign anastomotic stricture formation. Eleven patients (17.5%) who had a cervical anastomosis developed strictures compared with 13 (8.6%) in those who had intrathoracic anastomoses. Strictures developed in 12 patients (7.4%) with a whole stomach conduit and in 9 patients (19.6%) with a distal stomach conduit. Anastomotic recurrence occurred in 8 patients (3.7%); none had a histologically involved resection margin. CONCLUSIONS: The single-layer, continuous, hand-sewn technique for esophageal anastomosis is safe and effective. Cervical anastomosis and use of the distal stomach were associated with more benign strictures.

Anastomosis, Surgical↗
PubMed2005

Safety of donor right hepatectomy without abdominal drainage: a prospective evaluation in 100 consecutive liver donors.

Although the role of routine abdominal drainage after liver resection for tumors has been questioned, abdominal drainage after donor right hepatectomy for live donor liver transplantation (LDLT) has been a routine practice in most transplant centers. The present study aimed to evaluate the safety of the procedure without abdominal drainage. A prospective study was performed on 100 consecutive liver donors who underwent right hepatectomy for LDLT from July 2000 to September 2003. Biliary anatomy was carefully studied with intraoperative cholangiography using fluoroscopy. The middle hepatic vein was included in the graft in all except 1 patient. Parenchymal transection was performed using an ultrasonic dissector. The right hepatic duct was transected at the hilum and the stump was closed with 6-O polydioxanone continuous suture. Absence of bile leakage was confirmed with methylene blue solution instilled through the cystic duct stump. The abdomen was closed after careful hemostasis without drainage in all donors. The median age of the donors was 36 years (range 18-56 years). Median operative blood loss and operating time were 350 mL (range 42-1,400 mL) and 7.5 hours (range 5.2-10.7 hours), respectively. None of the donors required any blood or blood product transfusion. There was no operative mortality. The median postoperative hospital stay was 8 days (range 5-30 days). Postoperative morbidity occurred in 19 patients (19%), most of which were minor complications. No donor experienced bile leakage, intraabdominal bleeding, or collection. None required surgical, radiologic, or endoscopic intervention for postoperative complications, except for 1 donor who developed late biliary stricture that required endoscopic dilatation. All donors were well with a median follow-up of 32 months (range 11-50 months). In conclusion, with detailed study of the biliary anatomy and meticulous surgical technique, donor right hepatectomy can be safely performed without abdominal drainage. Abdominal drainage is not a mandatory procedure after donor hepatectomy in LDLT.

Abdomen↗
PubMed2005

CDX2 co-localizes with liver-intestine cadherin in intestinal metaplasia and adenocarcinoma of the stomach.

CDX2 and liver-intestine (LI)-cadherin are intestine-specific markers and both are physiologically expressed in the small intestine and colon. Recent studies have demonstrated that CDX2 regulates LI-cadherin gene (CDH17) expression in colorectal cancer. The present study investigated the relationship of CDX2 and LI-cadherin expression in gastric cancer. One hundred and nine pairs of tumour and non-cancerous gastric mucosa were collected from gastrectomy specimens. Protein expression levels of CDX2 and LI-cadherin were determined by immunohistochemical staining. Semi-quantitative RT-PCR showed that the mRNAs of both CDX2 and CDH17 were highly expressed in tumour compared with non-cancerous mucosa. Overexpression of CDX2 was significantly associated with CDH17 in gastric adenocarcinoma. Furthermore, the expression of CDX2 and LI-cadherin proteins was strongly coupled in intestinal metaplasia. In conclusion, overexpression of CDH17 is significantly associated with CDX2.

Adenocarcinoma↗
PubMed2005

Celecoxib compared with lansoprazole and naproxen to prevent gastrointestinal ulcer complications.

PURPOSE: Selective cyclooxygenase-2 (COX-2) inhibitors cause significantly fewer peptic ulcers than conventional nonselective nonsteroidal anti-inflammatory drugs (NSAIDs) in patients at low risk or high risk for peptic ulcers. On the other hand, proton pump inhibitor co-therapy has also been shown to be effective in preventing relapse of peptic ulcers in high-risk patients using nonselective NSAIDs. We compared the efficacy of a selective COX-2 inhibitor with that of proton pump inhibitor co-therapy in the reduction in the incidence of ulcer relapse in patients with a history of NSAID-related peptic ulcers. MATERIALS AND METHODS: For this study, we recruited 224 patients who developed ulcer complications after NSAID use. We excluded patients who required concomitant aspirin treatment and who had renal impairment. After healing of ulcers and eradication of Helicobacter pylori, patients were randomly assigned to treatment with celecoxib 200 mg daily (n = 120) or naproxen 750 mg daily and lansoprazole 30 mg daily (n = 122) for 24 weeks. The primary endpoint was recurrent ulcer complications. RESULTS: During a median follow-up of 24 weeks, 4 (3.7%, 95% confidence interval [CI] 0.0%-7.3%) patients in the celecoxib group, compared with 7 patients (6.3%, 95% CI 1.6%-11.1%) in the lansoprazole group, developed recurrent ulcer complications (absolute difference -2.6%; 95% CI for the difference -9.1%-3.7%). Celecoxib was statistically non-inferior to lansoprazole co-therapy in the prevention of recurrent ulcer complications. Concomitant illness (hazard ratio 4.72, 95% CI 1.24-18.18) and age 65 years or more (hazard ratio 18.52, 95% CI 2.26-142.86) were independent risk factors for ulcer recurrences. Significantly more patients receiving celecoxib (15.0%, 95% CI 9.7-22.5) developed dyspepsia than patients receiving lansoprazole (5.7%, 95% CI 2.8-11.4. P = .02). CONCLUSIONS: Celecoxib was as effective as lansoprazole co-therapy in the prevention of recurrences of ulcer complications in subjects with a history of NSAID-related complicated peptic ulcers. However, celecoxib, similar to lansoprazole co-therapy, was still associated with a significant proportion of ulcer complication recurrences. In addition, more patients receiving celecoxib developed dyspepsia than patients receiving lansoprazole and naproxen.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2005

Periprosthetic femoral fractures--a comparison between cemented and uncemented hemiarthroplasties.

Over a 2-year period, 244 patients underwent hemiarthroplasty for a displaced intracapsular femoral neck fracture. Seventy patients had a cementless Austin-Moore prosthesis (AMP) inserted and 174 patients were treated using a cemented Thompson hemiarthroplasty. All the AMPs were inserted by or under the supervision of an orthopaedic consultant. Five patients (7%) from the AMP group sustained a periprosthetic femoral fracture. Two were iatrogenic and three occurred postoperatively after a simple fall. The fractures occurred proximally around the prosthesis (Johansson type I). Four required revision surgery. There were no periprosthetic femoral fractures in the Thompson group. When compared to the cemented Thompson hemiarthroplasties, the number of periprosthetic femoral fractures was significantly greater with the AMP. Patients in the AMP group were significantly older, although there was no significant difference in ASA grade between the two groups. There was no significant difference in age or gender between those who sustained a periprosthetic fracture and those who did not. These findings suggest that due to the increased risk of periprosthetic femoral fracture, cemented hemiarthroplasty is preferable. Furthermore, with modern cementing techniques, elderly frail patients appear to tolerate bone cement, which may serve to reinforce an osteoporotic proximal femur.

Aged↗
PubMed2005

Computed tomography guided management of interfractional patient variation.

Interfractional patient variation occurs regularly and considerably during the radiotherapy course. Consequently, a generic but large planning target margin has to be applied when patient treatment plan design based on a single pre-treatment computed tomography scan is used to guide multifraction radiation treatment, which creates a major limiting factor for radiotherapy improvement. Planning target margins can be significantly reduced using multiple (or 4-dimensional) image feedback management in the routine treatment process. The most effective method in multiple-image feedback management of radiotherapy is the adaptive control methodology. The adaptive radiotherapy technique aims to customize each patient's treatment plan to patient-specific variation by evaluating and characterizing the systematic and random variations through image feedback and including them in adaptive planning. Adaptive radiotherapy will become a new treatment standard, in which a predesigned adaptive treatment strategy, including the schedules of imaging and replanning, will eventually replace the predesigned treatment plan in the routine clinical practice.

Dose Fractionation, Radiation↗