Interlaboratory assay reproducibility study for loss of heterozygosity on chromosome 18 (18q LOH) in colon cancer

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Background: 18q LOH may be a useful marker in stage II colon carcinoma to assess who needs adjuvant chemotherapy. The objective of this study was to evaluate the intra- and inter-laboratory reproducibility of an assay for 18q LOH that is similar to the integral assay used in E5202, the current Intergroup phase III stage II colon carcinoma clinical trial. Methods: Specimens from 130 stage II/III colon cancer patients were obtained from the Cooperative Human Tissue Network and evaluated at three different laboratories. Samples were divided into subsamples, coded and distributed. Each laboratory used similar equipment in an established PCR protocol with 5 dinucleotide repeats. Starting materials used both histologic sections and extracted DNA samples of tumor and non-neoplastic tissue obtained only by scalpel microdissection. LOH was defined as tumor/normal peak ratio that was >1.35 or <0.67 without microsatellite instability (MSI). Tumors were categorized as either MSI+, LOH + or -, uninformative/monoallelic, or unevaluable (DNA not amplifiable). Standard tests assessed reproducibility of both the numerical ratios and the tumor 18q LOH status. Results: Sample quality issues prevented analysis of 13 tumors (10%). The frequency of 18q LOH was 64%. The probability of agreement on the same tumor evaluated twice was 92% (Cohen's kappa 0.83). Intra-class correlation coefficients for individual markers were consistently over 0.90. Tissue specimens must have high (>85%) tumor cell content for reproducibility. Differences among patients affected reproducibility much more than effects of laboratory and sample type (DNA vs. histologic section). Conclusions: This study validates reproducibility of the 18q LOH assay for both clinical categorization of status and numerical ratios if samples are high quality and appropriate for scalpel microdissection.

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Insulin for type 2 diabetes: choosing a second-line insulin regimen

Guidance has been published on the choice of initial insulin regimen for patients with type 2 diabetes [NPH (isophane) insulin or a long-acting insulin analogue] but not on how to choose a second regimen when glycaemic control becomes unsatisfactory.

AIMS

To develop pragmatic clinical guidance for choosing a second-line insulin regimen tailored to the individual needs of patients with type 2 diabetes after failure of first-line insulin therapy.

METHODS

Formulation of a consensus by expert panel based on published evidence and best clinical practice, taking into account patient preferences, lifestyle and functional capacity.

RESULTS

Six patient-dependent factors relevant to the choice of second-line insulin regimen and three alternative insulin regimens (twice-daily premixed, basal-plus and basal-bolus) were identified. The panel recommended one or more insulin regimens compatible with each factor, emphasising the fundamental importance of a healthy lifestyle that includes exercise and weight reduction. These recommendations were incorporated into an algorithm to provide pragmatic guidance for clinicians.

CONCLUSION

The three alternative insulin regimens offer different benefits and drawbacks and it is important to make the right choice to optimise outcomes for patients.

Neurologic complications of arteriovenous malformation embolization using liquid embolic agents

BACKGROUND AND PURPOSE

Embolization of arteriovenous malformations (AVMs) is commonly used to achieve nidal volume reduction before microsurgical resection or stereotactic radiosurgery. The purpose of this study was to examine the overall neurologic complication rate in patients undergoing AVM embolization and analyze the factors that may determine increased risk.

MATERIALS AND METHODS

We performed a retrospective review of all patients with brain AVMs embolized at 1 center from 1995 through 2005. Demographics, including age, sex, presenting symptoms, and clinical condition, were recorded. Angiographic factors including maximal nidal size, presence of deep venous drainage, and involvement of eloquent cortex were also recorded. For each embolization session, the agent used, number of pedicles embolized, the percentage of nidal obliteration, and any complications were recorded. Complications were classified as the following: none, non-neurologic (mild), transient neurologic deficit, and permanent nondisabling and permanent disabling deficits. The permanent complications were also classified as ischemic or hemorrhagic. Modified Rankin Scale (mRS) scores were collected pre- and postembolization on all patients. Univariate regression analysis of factors associated with the development of any neurologic complication was performed.

RESULTS

Four hundred eighty-nine embolization procedures were performed in 192 patients. There were 6 Spetzler-Martin grade I (3.1%), 26 grade II (13.5%), 71 grade III (37.0%), 57 grade IV (29.7%), and 32 grade V (16.7%) AVMs. Permanent nondisabling complications occurred in 5 patients (2.6%) and permanent disabling complications or deaths occurred in 3 (1.6%). In addition, there were non-neurologic complications in 4 patients (2.1%) and transient neurologic deficits in 22 (11.5%). Five of the 8 permanent complications (2.6% overall) were ischemic, and 3 of 8 (1.6% overall) were hemorrhagic. Of the 178 patients who were mRS 0-2 pre-embolization, 4 (2.3%) were dependent or dead (mRS >2) at follow-up. Univariate analysis of risk factors for permanent neurologic deficits following embolization showed that basal ganglia location was weakly associated with a new postembolization neurologic deficit.

CONCLUSION

Embolization of brain AVMs can be performed with a high degree of technical success and a low rate of permanent neurologic complications.

Does a full bladder aid upper tract visualization in magnetic resonance urography?

The aim of this study was to evaluate whether a full bladder improved the visualization of the upper renal tract during magnetic resonance urography (MRU). Twenty volunteers were recruited into the study. The MRU imaging was carried out on a 1.5-T MR system. Imaging was carried out in the coronal plane using a half-Fourier acquired single-shot turbo-spin-echo technique. All volunteers were examined in two separate MRU studies to visualize the urinary tract. The first study was carried out with a 'full' bladder followed by a study with an 'empty' bladder, leading to a total of 40 examinations. Two radiologists then reviewed maximum intensity projection images from both 'full' and 'empty' studies independently. Both left and right upper tracts were divided into five segments. A three-point grading system was used to evaluate visualization. Excellent visualization = 3, good visualization = 2 and poor visualization = 1. Maximum score per patient was 30. Results were tabulated and analysed using an Excel database. The average score for visualization for the 'full' bladder group was 22.1/30 (73.8%) and the average score for the empty bladder was 16.2/30 (54%). Overall improvement in visualization was 5.9/30 (19.8%). There was strong interobserver agreement, with a concordance value of 92.5%. The MRU carried out in healthy young adult volunteers with a full bladder allows improved visualization of the upper tracts.

A review of weight loss interventions for adults with intellectual disabilities

Obesity is more prevalent in adults with intellectual disabilities than in the general population, and has been shown to contribute to their reduced life expectancy, and increased health needs. Relatively few studies have examined the effectiveness of weight loss interventions for adults with intellectual disabilities. However, there is evidence to support interventions that take account of the context of the lives of adults with intellectual disabilities, including carer involvement in interventions. To reduce the health inequalities experienced by adults with intellectual disabilities, there is a clear need to develop accessible, evidence-based clinical weight management services.

Long-term maintenance capecitabine and celecoxib improved clinical outcomes by targeting colorectal cancer micrometastasis

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Background: Role of mainteance therapy after achieving complete response (CR) remain undefined for patients with metasatic colorectal cancer. We studied prognostic and treatment factors including maintenance capecitabine and celecoxib (XCEL) in all 19 unresectable metastatic colorectal cancer patients (pts) who had CR from the prior XCEL study. Methods: Event charts are used to summarize the timeline of the various treatments. Kaplan-Meier survival estimates and univariate log-rank tests were used to evaluate RFS and OS as time from CR. Prognostic and treatment factors included: tumor size, metastasis number (9 solitary disease), site (13 being extrahepatic), stage on diagnosis (stage II versus III/IV), disease free interval prior to stage IV disease, surgery (5 R0, 3 R1–2 resections), lactate dehydrogenase levels, first-line irinotecan chemotherapy, radiation (9 pts ≥ 45 Gy, 3 Pts < 45 Gy), and maintenance XCEL (duration 0–50.3 months). Results: Nine of 19 patients experienced recurrence (median 13 months after CR), and 4 died during the follow-up period (median 31 months after CR). The 2-year RFS for the unresected and R1–2 resected patients was 71% versus 20% for the R0 resected patients (p = 0.07). This paradoxical RFS pattern corresponded to a RFS advantage for maintenance XCEL (p = 0.002), but not any other prognostic or treatment factors. All relapses occurred in situ following discontinuation of XCEL except for the surgical cases. Patients undergoing maintenance XCEL also benefited in OS (p = 0.04). The median OS from XCEL and from onset of metastasis reached 51.9 months (95% CI, 45 months- not reached [NR]) and 73.3 months (95% CI, NR-NR months) respectively. Conclusions: Maintenance XCEL targets colorectal micrometastases and produces a paradoxical RFS and OS advantage among the high-risk unresected/R1–2 resected patients than R0 resected patients. Prospective studies are warranted to validate roles of maintenance XCEL in the treatment of colorectal micrometastases.

No significant financial relationships to disclose.

The prevalence and determinants of obesity in adults with intellectual disabilities

People with intellectual disabilities experience significant health inequalities compared with the general population, including a shorter life expectancy and high levels of unmet health needs. Another accepted measure of health inequalities, the prevalence of obesity, has been shown to be higher in adults with intellectual disabilities than in the general population. While the factors contributing to the increased prevalence among adults with intellectual disabilities are not well understood, the high rates of obesity among younger adults highlight the need for further research involving children and adolescents with intellectual disabilities. To take forward the priorities for research and the development of effective, accessible services, there is a need for collaboration between professionals working in the fields of intellectual disabilities and obesity.

Diagnostic fine-needle aspiration in postoperative wound infections is more accurate at predicting causative organisms than wound swabs

INTRODUCTION

Postoperative wound infections are common. Antibiotics are often prescribed empirically, usually in the absence of any microbiological sensitivity data. This study demonstrates the role of fine-needle aspiration microbiology (FNAM) in determining the causative organisms in these wounds compared to wound swabs taken from the same patients.

PATIENTS AND METHODS

A total of 20 patients with clinical signs of soft tissue infection were tested using wound swabs and fine-needle aspiration.

RESULTS

Six of the wound swabs yielded a single organism but 16 out 20 of the FNAM group yielded a single organism (P = 0.002).

CONCLUSIONS

The FNAM approach allows antibiotic sensitivities to be obtained enabling specific antimicrobial therapy to be implemented early. FNAM also has a higher yield of cultures than wound swabs. Cellulitic areas can be sampled even when use of wound swabs is not possible.

Consent gained from patients after breast surgery for the use of surplus tissue in research: an exploration

OBJECTIVES

(1) To investigate the quality of consent gained for the use in research of tissue that is surplus after surgery. (2) To compare the use of two consent forms: a simple locally introduced form and a more complex centrally instigated form. (3) To discuss the attitudes of patients towards the use of their surplus tissue in research.

DESIGN

Data were collected through interviews and analysed with a combination of quantitative and qualitative analytical techniques.

PARTICIPANTS AND SETTING

Patients of the breast care unit at a teaching hospital were interviewed at home or in a quiet room at the hospital.

RESULTS

57 people were interviewed out of 81 approached, between October 2003 and March 2004. Most participants had a poor level of knowledge about the consent they had given, but reported being happy about having given it. The patients who had signed the locally introduced form had considerably more knowledge than those who had signed the centrally instigated form (z = -2.56; p<0.05). Participants considered being well informed to be less important than believing that their opinions were valued and respected.

CONCLUSIONS

The findings suggest that traditional models of informed consent are not universally applicable and, in this case, seem to overstate what people wish to know. The simple consent form achieved a better quality of informed consent and provided a better model of practice than the complex form, and it seemed that a focused approach to consent seeking is more effective and acceptable than more complex approaches.

Immunological differences between susceptible and resistant sheep during the preclinical phase of scrapie infection

In order to investigate the relationship between the immune response to scrapie infection and genetic susceptibility to the disease in sheep, immune cell subsets and prion protein (PrP) expression were determined in susceptible and resistant Suffolk sheep in the preclinical phase of infection. At 6 months of age, 12 ARQ/ARQ (susceptible) and nine ARR/ARR (resistant) scrapie-free Suffolk lambs were challenged subcutaneously with scrapie inoculum. Prefemoral lymphadenectomies were carried out at 14 and 180 days post-inoculation (p.i.) and serial bleeds were collected at monthly intervals for up to 1 year p.i. An indirect double-labelling procedure was carried out on peripheral blood mononuclear cells (PBMCs) and lymph node cell preparations and analysed using flow cytometry. Prior to scrapie challenge, significantly more PrP+cells were detected in PBMCs from the susceptible sheep. Furthermore, following challenge, significantly more CD8+andγΔ+T cells were detected in the PBMCs of the resistant sheep. However, at both 14 and 180 days p.i, CD21+cell expression was significantly higher in the lymph node preparations of the susceptible sheep. In contrast, more CD4+cells were detected in the lymph nodes of the resistant sheep at both time points. It was concluded that significant differences in immune cell subsets and PrP expression occur between ARQ/ARQ and ARR/ARR Suffolk sheep in the preclinical phase of infection.

Inequality in uptake of orthodontic services

OBJECTIVE

The purpose of this ecological study was to investigate the relationship between uptake of orthodontic services and factors that might influence receipt of care at a population level.

METHOD

The dental practice board supplied data on claims for courses of active orthodontic treatment from April 2001 to March 2002 for children from the former county of Avon. These data were analysed in relation to deprivation, living in an urban/rural setting and the proportion of the population from a black or minority ethnic group (BME).

RESULTS

In Avon, children from deprived and rural areas were significantly less likely to be undergoing an active course of orthodontic treatment. Children from an area with a high proportion BME were significantly more likely to be undergoing treatment.

CONCLUSION

This research demonstrates that children from more deprived and rural communities in Avon are less likely to receive orthodontic treatment. This has important policy implications for primary care trusts that have a responsibility to ensure equal access to care for all of their children.

Array comparative genomic hybridization for diagnosis of developmental delay - an exploratory cost-consequences analysis

A major application of array comparative genomic hybridization (aCGH) is to define a specific cause in children with undiagnosed learning and developmental disability (LDD). Medical notes for 46 consecutive patients selected for aCGH analysis by clinical dysmorphologists were abstracted for clinical investigations related to LDD and a cost-consequences analysis was performed. aCGH analysis was completed in 36 cases and five diagnostic chromosomal anomalies were identified (13.8%). The number of investigations undertaken on each child varied. With aCGH estimated to cost 590 British Pound per case, if aCGH had been undertaken after negative standard initial tests for LDD investigation, the additional cost would be 2399 British Pound per positive case. If the cost of aCGH was reduced to 256 British Pound per case (approximately 350 Euro), aCGH becomes cost neutral. All chromosomal anomalies detected by aCGH had a de Vries score of > or =5. If aCGH had only been used for individuals with a score of > or =5, the sensitivity increased to 21.7% yielding a cost of 1087 British Pound per positive case identified. Pre-selection of cases for aCGH based on de Vries criteria has a major economic impact on introducing aCGH into clinical practice. Prospective studies are required to explore the long-term costs and consequences of aCGH and identify when aCGH may provide the most benefit at least cost.

Developing audit standards required for outbreaks of communicable diseases—lessons from a mumps outbreak

BACKGROUND

A mumps outbreak occurred in 2004-05 in England and Wales. The outbreak in the Avon area of England led to mass vaccination of 16- to 24-year-olds with the measles, mumps and rubella vaccine (MMR). The response to the outbreak was audited. Literature and web searches for audit standards were undertaken, and experts in the field were contacted. No comprehensive audit standards for outbreaks of communicable diseases were found. This article describes an approach to developing audit standards for outbreaks of communicable diseases.

METHODS

Audit standards were developed based on the memorandum of understanding between the National Health Service (NHS) and Health Protection Agency. The audit was undertaken involving 25 staff.

RESULTS

The audit standards developed identified many areas for improvement including training, strategic co-ordination, inter-organizational communication, consistency and timeliness of communication. Conducting the audit was problematic because there were not pre-defined audit standards.

CONCLUSIONS

Audit standards should be developed, which include issues relating to the structure, process and outcome of responses to outbreaks. The development of audit standards for the management of outbreaks is crucial to evaluate outbreak control and make necessary improvements.

Intramuscular injections into the buttocks: Are they truly intramuscular?

AIM

To radiologically determine if intramuscular (IM) injections into the buttocks are truly intramuscular.

MATERIALS AND METHODS

This was a prospective study conducted during a 6 month period beginning in October 2004. Fifty inpatients were recruited from a single tertiary referral hospital. Approval was obtained from the hospital research ethics committee and informed written consent was acquired from all participants. Prior to computerised tomography (CT), each patient received an IM injection of their prescribed medication along with 1 mL of air into the upper outer quadrant of the buttocks. CT images were subsequently analyzed by two radiologists to determine the position of the injected air bubble and to assess whether it was intramuscular or subcutaneous in position. Body mass index (BMI), distance to injection site, subcutaneous fat and muscle thickness were also measured.

RESULTS

Overall, only 32% (n=16/50) of patients had intramuscular injections, with the majority of injections (68%, n=34/50) being subcutaneous. When analysed by gender, 56% (n=14/25) of males had intramuscular injections while in females, the efficacy rate was significantly lower at 8% (n=2/25).

CONCLUSION

The majority of assumed intramuscular injections are actually subcutaneous.