Prostate brachytherapy post implant dosimetry: Timing matters

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Background: Permanent seed implant (PSI) brachytherapy is a common treatment modality for low-risk prostate cancer. Post implant dosimetry (PID) is utilized to asses the quality of the implant. Significant prostate swelling occurs as a result of the implant procedure, and this swelling subsides over time. PID completed on Day 0 after the implant procedure captures the prostate swelling from the procedure. Conversely, PID completed one month later does not have this swelling. PID can therefore show great variation, depending on the timing of the analysis. It is hypothesized that PID completed on Day 0 demonstrates lower dosimetric parameters than PID completed one month later. Methods: Thirteen low risk prostate cancer patients, (Stage ≤ T2, PSA < 13.9, Gleason Score ≤7) were implanted with 125Iodine seeds, with a prescription dose of 145Gy to the prostate plus a 5mm margin. Computed Tomography (CT) PID was completed for each patient on day 0 and on average 33 days following the implant. The prostate was contoured on each axial CT image and the data was analyzed using commercially available PSI planning software. The dose which encompassed 90% of the prostate volume (D90) was calculated for day 0 and day 33 PID. Results: On average, the prostate volume contoured was larger on day 0 PID (Avg. 44.9 cc; range 19–97 cc) compared to day 33 PID (Avg. 38.9 cc; range 18–59 cc) (P = 0.068). The D90 values however, were significantly higher on day 33 PID (Avg.163.7 Gy; range 125–212 Gy) than on day 0 PID (Avg.149 Gy; range 112–166 Gy) (P = 0.003). This D90 relationship was even demonstrated paradoxically in two patients whose contoured prostate volume was larger on the day 33 PID as compared to the day 0 PID. Conclusions: Timing does matter in the analysis of post implant dosimetry for PSI brachytherapy. The D90 values were significantly greater on day 33 PID compared to Day 0 PID while the contoured prostate volumes were not. Future studies which use PID planning to evaluate implant quality should specify the timing of the PID, as this would facilitate cross study comparison.

No significant financial relationships to disclose.

Patients' preference for administration of endocrine treatments by injection or tablets: results from a study of women with breast cancer

BACKGROUND

Endocrine therapies for advanced breast cancer include tablets and intramuscular injections. When treatments have similar efficacy and tolerability profiles, addressing preferences about routes of administration is important.

PATIENTS AND METHODS

Two hundred and eight women>2 years post-breast cancer diagnosis were interviewed about their preferences for daily tablets or monthly intramuscular injections. Health-care professionals treating the women estimated patients' preferences.

RESULTS

Sixty-three per cent of patients preferred tablets, 24.5% preferred the injection and 12.5% had no preference. The most cited reasons for tablet preference were convenience and dislike of needles; for injection preference, adherence and convenience. Variables associated with preferences were body mass index, educational level, attitudes towards injections and efficacy perceptions. Estimates about patients' preferences by health-care professionals varied widely. When asked to imagine scenarios where injections produced fewer hot flushes, or where two injections monthly improved efficacy, injection preference increased to 60.6% and 74.5%, respectively. Disturbingly, approximately 50% of patients admitted they sometimes forgot or chose not to take their current oral medication.

CONCLUSIONS

The majority of breast cancer patients preferred hormone therapy via daily tablets rather than monthly injections. Information about side-effects or improved efficacy altered these preferences. Adherence to treatment cannot be assumed; patients' preferences about drug administration may influence this.

C1 inhibitor deficiency: consensus document

We present a consensus document on the diagnosis and management of C1 inhibitor deficiency, a syndrome characterized clinically by recurrent episodes of angio-oedema. In hereditary angio-oedema, a rare autosomal dominant condition, C1 inhibitor function is reduced due to impaired transcription or production of non-functional protein. The diagnosis is confirmed by the presence of a low serum C4 and absent or greatly reduced C1 inhibitor level or function. The condition can cause fatal laryngeal oedema and features indistinguishable from gastrointestinal tract obstruction. Attacks can be precipitated by trauma, infection and other stimulants. Treatment is graded according to response and the clinical site of swelling. Acute treatment for severe attack is by infusion of C1 inhibitor concentrate and for minor attack attenuated androgens and/or tranexamic acid. Prophylactic treatment is by attenuated androgens and/or tranexamic acid. There are a number of new products in trial, including genetically engineered C1 esterase inhibitor, kallikrein inhibitor and bradykinin B2 receptor antagonist. Individual sections provide special advice with respect to diagnosis, management (prophylaxis and emergency care), special situations (childhood, pregnancy, contraception, travel and dental care) and service specification.

Spatial and temporal structure of edge-localized modes

This Letter provides information on the spatial and temporal structure of periodic eruptions observed in magnetically confined laboratory fusion plasmas, called edge-localized modes (ELMs), and highlights similarities with solar eruptions. Taken together, the observations presented in this Letter provide strong evidence for ELMs being associated with a filamentlike structure. These filaments are extended along a field line, are generated on a 100 micros time scale, erupt from the outboard side, and connect back into the plasma. Such structures are predicted by a theoretical model based on the "ballooning" instability, developed for both solar and tokamak applications.

Protecting the terminus: t-loops and telomere end-binding proteins

Telomeric DNA is composed of a region of duplex telomeric tract followed by a single-strand overhang on the 3' G-rich strand. The DNA is packaged by proteins that associate directly with the single- and double-strand regions of the telomeric tract and by their associated proteins. This review discusses the evidence that G-strand overhangs are present on both ends of eukaryotic chromosomes and the steps needed to generate these overhangs. The overhangs are protected by specialized G-overhang-binding protein and/or invasion by the overhang of the duplex region of the telomeric tract to form a structure called a 't-loop'. The G-overhang-binding proteins identified from different species are described, and their properties compared. The data supporting the existence of t-loops at native telomeres is discussed, and the conditions required to promote their in vitro formation are presented.

A Markov model of treatment of newly diagnosed epilepsy in the UK. An initial assessment of cost-effectiveness of topiramate

Long-term comparative trials among newer antiepileptic drugs are lacking; therefore decision models are needed to guide treatment decisions. The goal of this study was to develop an economic model of newly diagnosed epilepsy in the UK and to provide the first assessment of topiramate. A Markov model was developed combining data from clinical trials, cost-of illness, mortality, and utility studies. Expected costs and utilities associated with treatment strategies (first- and second-line treatments) were compared to find the cost-effectiveness frontier. First- and second-line monotherapy with topiramate or carbamazepine in partial seizures was less costly and more effective than other scenarios. In generalised seizures first-line topiramate was cost-effective with valproate or lamotrigine as second-line treatments depending on the set of utilities used. Models provide a relevant framework within which costs and health gains of antiepileptic drugs treatment options can be studied. Our findings are further evidence of the promising role of topiramate for patients with newly diagnosed epilepsy.

Attitudes to Prophylactic Surgery and Chemoprevention in Australian Women at Increased Risk for Breast Cancer

BACKGROUND

Because of the uncertain efficacy of breast cancer screening in women at increased risk of developing breast cancer, bilateral prophylactic oophorectomy and mastectomy are considered management options for high-risk women. Data on the attitudes to prophylactic strategies of high-risk women who have not attended specialist clinics are needed to ascertain the need for patient education and provide the basis for planning of support services.

METHODS

Three hundred seventy-one women unaffected by cancer and with unknown mutation status from families with a dominantly inherited susceptibility to breast cancer, recruited through a large Australian population-based, epidemiological study, were assessed using a mailed self-administered questionnaire with validated measures of psychological outcome.

RESULTS

Sixteen percent of women reported considering prophylactic mastectomy, and 1% had already had the procedure. Among women with a family history of breast/ovarian cancer, 33% had considered and 5% had already had a prophylactic oophorectomy. Twenty-three percent of women reported considering taking tamoxifen if it were shown to prevent breast cancer. Consideration of prophylactic oophorectomy (OR = 1.51 for a 10% change in perceived risk, 95% CI 1.14-1.99, p = 0.0045) and tamoxifen (OR = 1.14 for a 10% change in perceived risk, 95% CI 1.002-1.30, p = 0.047) were positively associated with perceived cancer risk.

CONCLUSIONS

Attitudes to prophylactic surgery and psychological distress levels in high-risk women participating in an epidemiological study appear to be comparable to those of women attending familial cancer clinics and indicate that women attending high-risk clinics may be representative of the larger population of women at increased risk.

Extended formulary nurse prescribing--another saliva substitute roadblock

United Kingdom family physicians, General Practitioners (GPs), are allowed to prescribe from a Department of Health-approved list of non-medicines (the 'ACBS' list) which includes a majority of proprietary saliva substitutes. Independent nurse prescribing, introduced in 2001, has improved patient access to effective remedies for a wide range of common medical problems. Further qualified 'extended formulary nurse prescribers' have access to a limited range of prescription medicines, and all non-prescription medicines that GPs may currently prescribe. Despite their specified role in the management of oral complications encountered in palliative care, a similar anomaly in NHS rules that prevents dental practitioners from prescribing ACBS listed saliva substitutes also prevents nurses from prescribing them. Sadly, patients are suffering poorer access to simple and effective remedies to conditions such as xerostomia - a condition that has recognised impact on their quality of life.

Measuring costs and consequences in economic evaluation in asthma

Formal economic evaluation is playing an increasingly important role in health-care decision-making. This is shown by the requirement to present economic data to support applications for public reimbursement for new pharmaceuticals in Australia and the provinces of Canada, and by the appraisal process initiated by the National Institute for Clinical Excellence in the U.K. This growing role of economic analysis applies as much to the field of asthma as anywhere. This paper provides a detailed review of applied economic studies in asthma. The review is used to explore a range of methodological issues in the field including the choice of perspective and maximand, whether to use disease-specific or generic measures of outcome and whether decision-makers should receive disaggregated cost and consequence data or results that focus on an incremental cost-effectiveness ratio. It is concluded that, given the heterogeneity in decision-makers' objectives and constraints, economic studies should be planned and executed in such a way as to maximize flexibility in how results are presented.

Use of videotape to assess mobility in a controlled randomized crossover trial of physiotherapy in chronic multiple sclerosis

OBJECTIVES

To determine to what degree assessment of mobility based on comparison of videotape recordings before and after courses of physiotherapy in patients with chronic multiple sclerosis (MS) is reliable, correlates with 'live' assessments and indicates benefit.

DESIGN

Prospective data collection within a randomized crossover controlled trial of physiotherapy at home, as an outpatient, or 'no therapy' in 40 patients.

SETTING

Hospital outpatients: outpatient and home physiotherapy.

OUTCOMES

Mobility change based on a comparison of short video recordings before and after each treatment period was scored independently by two physiotherapists blinded to therapy type and other measures of outcome. Scores were compared with changes in the Rivermead Mobility Index (RMI) and other indices assessed by a physiotherapist in the patient's home.

RESULTS

The two video observers agreed substantially on patient outcome. Changes in walking based on video correlated with RMI for home treatment (r = 0.41, p = 0.008) but not for hospital or no treatment periods (r = 0.14 and 0.15): video changes correlated with the 'live' assessor's global change score inconsistently ('no therapy' r = 0.48, p = 0.002, hospital r = 0.30, p = 0.06 and home r = 0.17, p = 0.30 treatment periods). Based on video data alone, improved mobility was evident following home therapy for only one observer but not for the other or the averaged scores of both.

CONCLUSION

There was substantial agreement between two observers deciding on change in mobility based on independent blinded evaluation of short video sequences. However the correlations of these with 'live' assessments were variable. Physiotherapy had a less clear benefit on mobility based on video analysis alone compared with 'live' assessments. The study highlights the need for more objective measures of habitual mobility over longer periods.

Xenoendocrine disrupters-tiered screening and testing: filling key data gaps

The US Environmental Protection Agency (EPA) is developing a screening and testing program for endocrine disrupting chemicals (EDCs) to detect alterations of hypothalamic-pituitary-gonadal (HPG) function, estrogen (ER), androgen (AR) and thyroid hormone synthesis and AR and ER receptor-mediated effects in mammals and other animals. High priority chemicals would be evaluated in the Tier 1 Screening (T1S) battery and chemicals positive in T1S would then be tested (Tier 2). T1S includes in vitro ER and AR receptor binding and/or gene expression, an assessment of steroidogenesis and mammalian (rat) and nonmammalian in vivo assays (Table 1). In vivo, the uterotropic assay detects estrogens and antiestrogens, while steroidogenesis, antithyroid activity, (anti)estrogenicity and HPG function are assessed in a 'Pubertal Female Assay'. (Anti-) androgens are detected in the Hershberger Assay (weight of AR-dependent tissues in castrate-immature-male rats). Fish and amphibian assays also are being developed. The fathead minnow assay can identify EDCs displaying several mechanisms of concern, including AR and ER receptor agonists and antagonists and inhibitors of steroid hormone synthesis. An amphibian metamorphosis assay is being developed to detect thyroid-active substances. Several alternative mammalian in vivo assays have been proposed. Of these, a short-term pubertal male rat assay appears most promising. An in utero-lactational screening protocol also is being evaluated. For Tier 2, the numbers of endocrine sensitive endpoints and offspring (F1) examined in multigenerational tests need to be expanded for EDCs. Consideration should be given to tailoring T2, based on the results of T1S. Tier 1 and 2 also should examine relevant mixtures of EDCs. Toxicants that induce malformations in AR-dependent tissues produce cumulative effects even when two chemicals act via different mechanisms of action.

How many years do students study before graduating in medicine?

OBJECTIVES

The Faculty of Health Sciences at the University of the Witwatersrand is considering changing from a 6-year medical degree to a mainly graduate-entry 4-year degree. The objective of this study was to determine how long students currently take to qualify and how many years are spent studying for each medical graduate produced.

DESIGN

A retrospective study of 691 students registered in medicine at the University of the Witwatersrand in 1988, 1989 and 1990 was conducted by examining student progress records.

RESULTS

The study found that an average of 7.89 years was spent studying for each graduate produced, including tertiary studies before medicine, repeated years and intercalated science degrees. Five hundred and eighty-nine students (85%) graduated and 102 (15%) did not. Forty-eight per cent studied for 7 or more years before graduating, 21% completed degrees before or during their medical studies, and 21% of students repeated years.

CONCLUSION

The costs to the individual and society of the new 3 + 4-year degree structure would not be very different from those of the current 6-year structure.

Who needs sustainability?

Three inescapable factors face us at the turn of the century. First, the climate, and with it the supply of water, is becoming more variable. Regardless of whether this variability is the result of man-made global warming, it seems to be with us. Secondly, demand for water will increase; in many countries domestic water use is currently less than 25 1/personday and needs to increase if living conditions are to improve. In Great Britain, per capita use of water is low compared with many other western countries — including those that pay for water on a metered basis — and it is certain to rise as living standards improve. Thirdly, concern for the environment is likely to increase. We can counter the first problem only by ensuring that we have adequate water storage; most water storage in Great Britain and the rest of the world is in the ground. We need to counter the second by recognizing that the vast majority of public water use is non-consumptive, but that very little waste water is re-used efficiently. We need to counter the third by welcoming the concern but ensuring that the response is sensible. We must be prepared to question some of the accepted wisdom of the environmental movement, and remember that many of the developments in human history were non-sustainable. Do they represent environmental disasters, or human progress?

Budget impact model for determining the costs of introducing inhaled salmeterol/fluticasone propionate combination for the management of persistent asthma in France

A budget impact model was used to estimate the effect of introducing inhaled salmeterol/fluticasone propionate combination on asthma drug-related costs in France. The model is based on disease prevalence, drug use, drug acquisition cost and sales forecasting data specific to France. It takes the perspective of social security and has a time horizon of 1 year. All drug acquisition costs are adjusted for the average rate of reimbursement of asthma medications in France (77.3%). All costs are expressed in euros. The model shows that if patients receiving concurrent salmeterol plus fluticasone propionate (or budesonide plus formoterol switch to combined salmeterol/fluticasone propionate, the anticipated annual savings would be 2,691,580 and 1,916,966 euros, respectively. On a fixed budget 4067 additional patients could be treated if salmeterol/fluticasone propionate is substituted for concurrent salmeterol plus fluticasone propionate and an additional 2939 patients if the combination is used to replace concurrent budesonide plus formoterol. Overall, using sales forecasting data to estimate how many patients will switch to the new combination from their current therapy, it is estimated that the introduction of salmeterol/fluticasone propionate will increase the national expenditure in France on asthma medications by a maximum of 3%. This budget impact model shows that the introduction of inhaled salmeterol/fluticasone propionate combination is likely to have minimal impact on asthma-related medication costs in France. Moreover, the available data on the salmeterol/fluticasone propionate combination suggest that it is clinically effective, cost-effective and affordable to the French healthcare system.

Questionnaire survey of the views of the delegates at the European Cervical Spine Research Society meeting on the administration of methylprednisolone for acute traumatic spinal cord injury

STUDY DESIGN

A questionnaire survey.

OBJECTIVES

To collate and analyze the views of the delegates who attended the European Cervical Spine Research Society (CSRS) meeting on the use of methylprednisolone for acute traumatic spinal cord injury.

SUMMARY OF BACKGROUND DATA

The NASCIS II and III studies reported improved neurologic recovery in patients who were treated with methylprednisolone within 8 hours of their acute traumatic spinal cord injury. A number of reported commentaries have criticized these trials. A recent audit in the authors' regional spinal injuries unit in the United Kingdom found that a large percentage of patients were not receiving methylprednisolone. The authors decided to collate the views of the delegates at the CSRS regarding the use of steroids for acute traumatic spinal cord injury.

METHODOLOGY

A questionnaire was created that took into account the positive reported findings as well as the criticisms of the NASCIS studies. Delegates who attended the European CSRS meeting completed this questionnaire.

RESULTS

Seventy-five percent of the delegates answered that they used or recommended methylprednisolone in the treatment of acute traumatic spinal cord injury. Nevertheless, the delegates had an average of 1.5 reservations about administering methylprednisolone. The most common reservation was that they did not think the improvement conferred to the patients by administering methylprednisolone had been clinically or functionally proven. There were reservations about the validity of the statistical analysis used in the NASCIS studies and by the omission of a placebo group in NASCIS III. The majority of the delegates thought it was not medicolegally negligent to withhold the administration of methylprednisolone in the treatment of acute traumatic spinal cord injury.

CONCLUSION

The use of methylprednisolone in the treatment of acute traumatic spinal cord injury is still controversial. It would appear from a recent prospective audit at the authors' spinal injuries unit that a large percentage of patients in the United Kingdom are not receiving methylprednisolone. Because so much doubt exists, the NASCIS studies should be repeated.