Effect of ProSpare (PS), a rectal obturator, on inter- and intrafraction prostate motion and anorectal doses in prostate radiotherapy (RT)

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Background: PS is a single use, self-insertable endorectal device designed as a daily image-guidance tool for prostate cancer RT. Rectal filling is a significant factor in prostate motion. We investigated the effect of PS on inter- and intrafraction prostate motion and its effect on anorectal dosimetry. Methods: 19 patients with localized prostate cancer were randomized to receive prostate RT with PS either in the 1st or 2nd half of treatment. For each patient two planning CT scans were acquired, without and with PS. Contours were delineated by one physician and planned with a forward multi-segment technique to a dose of 74Gy/37F. Dose surface histograms were created (VODCA). In all patients, 3 electromagnetic transponders (EM) were implanted into the prostate and daily online image-guided RT was performed using either cone-beam CT (Elekta) or Calypso–based localization with tracking. Interfraction systematic (Σ) and random (σ) errors were estimated for bone matching without and with PS using EM position as reference. CTV-PTV margins were generated using the Van Herk formula. In-house code was used to analyse intrafraction motion recorded by Calypso of the EM centroid in the RL, SI and AP planes for individual fractions. A 2-way ANOVA test (SPSS v22) was used to determine if PS had an effect on maximal intrafraction prostate displacement. Results: See Table. Conclusions: PS affects the dosimetric pattern to the anal canal and rectum and this may impact GI toxicity. Also, PS stabilizes the prostate, which could enable reduced planning margins. PS will now be assessed in post-prostatectomy RT within a randomized controlled trial, POPS. Clinical trial information: 11814. [Table: see text] [Table: see text] [Table: see text]

Heavy-resistance exercise-induced increases in jump performance are not explained by changes in neuromuscular function

Post-activation potentiation (PAP) is the increased involuntary muscle twitch response to stimulation following strong contraction. The enhancement to whole-body explosive muscular performance (PE) after heavy-resistance exercise is often attributed to modulations in neuromuscular function that are proposed to reflect PAP, but the evidence to support this is equivocal. We assessed the neuromuscular basis of PE using transcranial magnetic stimulation (TMS) of the primary motor cortex, and electrical stimulation of the femoral nerve. Eleven male athletes performed heavy-resistance exercise with measures of countermovement jump (CMJ) pre- and 8 min post-exercise. Pre-exercise and after the final CMJ, single- and paired-pulse TMS were delivered during submaximal isometric knee-extensor contractions to measure corticospinal excitability, short-interval intracortical inhibition (SICI), and intracortical facilitation (ICF), with motor evoked potentials recorded from rectus femoris. Twitch responses to motor nerve stimulation during and post maximum-knee-extensor contractions were studied to quantify voluntary activation (VA) and potentiated twitch (Q_tw,pot ). The experimental protocol successfully induced PE (+4 ± 1% change in CMJ, P = 0.01), but no changes were observed for maximum voluntary force, VA, corticospinal excitability, SICI or ICF (all P > 0.05), and Q_tw,pot declined (P < 0.001). An enhancement of muscular performance after heavy-resistance exercise was not accompanied by PAP, or changes in measures of neuromuscular function.

Quantifying parental preferences for interventions designed to improve home food preparation and home food environments during early childhood

Though preparing healthy food at home is a critical health promotion habit, few interventions have aimed to improve parental cooking skills and behaviors. We sought to understand parents' preferences and priorities regarding interventions to improve home food preparation practices and home food environments during early childhood. We administered a discrete choice experiment using maximum difference scaling. Eighty English-speaking parents of healthy 1-4 year-old children rated the relative importance of potential attributes of interventions to improve home food preparation practices and home food environments. We performed latent class analysis to identify subgroups of parents with similar preferences and tested for differences between the subgroups. Participants were mostly white or black 21-45 year-old women whose prevalence of overweight/obesity mirrored the general population. Latent class analysis revealed three distinct groups of parental preferences for intervention content: a healthy cooking group, focused on nutrition and cooking healthier food; a child persuasion group, focused on convincing toddlers to eat home-cooked food; and a creative cooking group, focused on cooking without recipes, meal planning, and time-saving strategies. Younger, lower income, 1-parent households comprised the healthy cooking group, while older, higher income, 2-parent households comprised the creative cooking group (p < 0.05). The child persuasion group was more varied with regard to age, income, and household structure but cooked dinner regularly, unlike the other two groups (p < 0.05). Discrete choice experiments using maximum difference scaling can be employed to design and tailor interventions to change health behaviors. Segmenting a diverse target population by needs and preferences enables the tailoring and optimization of future interventions to improve parental home food preparation practices. Such interventions are important for creating healthier home food environments and preventing obesity starting from early childhood.

Magnitude of observer error using cone beam CT for prostate interfraction motion estimation: effect of reducing scan length or increasing exposure

OBJECTIVE

Cone beam CT (CBCT) enables soft-tissue registration to planning CT for position verification in radiotherapy. The aim of this study was to determine the interobserver error (IOE) in prostate position verification using a standard CBCT protocol, and the effect of reducing CBCT scan length or increasing exposure, compared with standard imaging protocol.

METHODS

CBCT images were acquired using a novel 7 cm length image with standard exposure (1644 mAs) at Fraction 1 (7), standard 12 cm length image (1644 mAs) at Fraction 2 (12) and a 7 cm length image with higher exposure (2632 mAs) at Fraction 3 (7H) on 31 patients receiving radiotherapy for prostate cancer. Eight observers (two clinicians and six radiographers) registered the images. Guidelines and training were provided. The means of the IOEs were compared using a Kruzkal-Wallis test. Levene's test was used to test for differences in the variances of the IOEs and the independent prostate position.

RESULTS

No significant difference was found between the IOEs of each image protocol in any direction. Mean absolute IOE was the greatest in the anteroposterior direction. Standard deviation (SD) of the IOE was the least in the left-right direction for each of the three image protocols. The SD of the IOE was significantly less than the independent prostate motion in the anterior-posterior (AP) direction only (1.8 and 3.0 mm, respectively: p = 0.017). IOEs were within 1 SD of the independent prostate motion in 95%, 77% and 96% of the images in the RL, SI and AP direction.

CONCLUSION

Reducing CBCT scan length and increasing exposure did not have a significant effect on IOEs. To reduce imaging dose, a reduction in CBCT scan length could be considered without increasing the uncertainty in prostate registration. Precision of CBCT verification of prostate radiotherapy is affected by IOE and should be quantified prior to implementation.

ADVANCES IN KNOWLEDGE

This study shows the importance of quantifying the magnitude of IOEs prior to CBCT implementation.

A prospective study comparing radiographer- and clinician-based localization for patients with metastatic spinal cord compression (MSCC) to assess the feasibility of a radiographer-led service

OBJECTIVE

To investigate whether there was parity between treatment fields localized by radiographers and clinicians, by comparing geographical variations and hence determining the feasibility of a radiographer-led service.

METHODS

23 patients with metastatic spinal cord compression (MSCC) were prospectively sampled. Four radiographers not involved in the original planning performed localization on each patient. The 92 localizations that they determined were compared with the clinician-approved fields. Agreement was defined as ≤0.5 cm between field length, width and three isocentre co-ordinates. To be feasible, agreement was required in a minimum of 97% of the cases. The potential time saved with a radiographer-led approach was also recorded.

RESULTS

Agreement between clinicians and radiographers was 97.8%. For all field parameters, the average differences were <0.3 cm and were significantly different from the 0.5-cm median (p < 0.0001) that would establish no agreement using Wilcoxon signed-rank test. The average (range) delay awaiting clinician approval was 54 min (4-141 min).

CONCLUSION

Strong agreement between radiographer and clinician localizations was established. It was also highlighted that time could be saved in the patient's pathway by removing the need to wait for clinician approval. We believe this supports a radiographer-led service.

ADVANCES IN KNOWLEDGE

This article is novel, as it is the first known comparison between clinicians and radiographers in the localization of MSCC radiotherapy. These data show the feasibility of introducing radiographer-led practice and a methodology that could be potentially transferred to investigate the localization parity for other treatment sites.

Dense WDM transmission at 2 μm enabled by an arrayed waveguide grating

We show, for the first time, dense WDM (8×20  Gbit/s) transmission at 2 μm enabled by advanced modulation formats (4-ASK Fast-OFDM) and the development of key components, including a new arrayed waveguide grating (AWGr) at 2 μm. The AWGr shows -12.8±1.78  dB of excess loss with an 18-dB extinction ratio and a thermal tunability of 0.108 nm/°C.

Initial UK Experience of Stereotactic Body Radiotherapy for Extracranial Oligometastases: Can We Change the Therapeutic Paradigm?

AIMS

To retrospectively review the toxicity and early outcome data from patients who have received stereotactic body radiotherapy (SBRT) for extracranial oligometastases at a single UK institution.

MATERIALS AND METHODS

Eligible patients had ≤3 extracranial metastases and performance status ≤2. Prior systemic therapy and radical treatment of oligometastastic relapse with any standard treatment modality was permitted. Patients with synchronous metastatic disease were excluded unless they had evidence of controlled primary disease after radical therapy. Follow-up consisted of clinical examination, biochemical and radiological assessments in accordance with standard clinical care. Progression events were defined using RECIST. Toxicity was evaluated using CTCAE v4.0. Local control, progression-free survival (PFS), freedom from widespread distant metastasis (defined as disease not amenable to further radical salvage therapy) and overall survival were calculated.

RESULTS

Between July 2011 and April 2014, 73 patients with 87 metastases received SBRT (range 1-3 per patient). The median follow-up was 14.5 months (range 0-26.4). The median PFS was 14.5 months (1 year PFS 57%, 2 year 28%); 1 year overall survival 96%, 2 year 79.8%; 2 year local control 88%. At 2 years, 46% of patients were free from widespread distant metastases. No ≥ grade 3 acute or late toxicity was observed.

CONCLUSION

At this time point, observed toxicity is minimal with excellent local control rates. This promising treatment paradigm requires further investigation in the context of a randomised controlled trial to establish if the addition of SBRT to standard care improves survival outcomes.

CT angiography-guided single-stage release of adjacent webspaces in non-Apert syndactyly

We describe the CT angiography protocol and surgical technique utilized at our institution for single-stage release of adjacent web-spaces in non-Apert syndactyly. In a series of seven consecutive hands we analyse syndactyly anatomy, CT angiographic findings, operative details, and complications. Outcomes were assessed with a functional activity evaluation, range of motion, and a parental visual analogue scale. Seven affected hands in four patients underwent single-stage release of adjacent webspaces. In all cases, the CT angiogram correctly predicted the presence of at least one artery supplying each digit. There were no cases of digital ischemia or loss. Angiographically guided, single-stage release of adjacent webspaces is technically feasible and benefits patients by reducing the number of surgical stages and allowing complete release to be achieved at an earlier age compared with the standard multi-stage approach.

LEVEL OF EVIDENCE

IV.

10 Gb/s InP-based Mach-Zehnder modulator for operation at 2 μm wavelengths

We report on the first InP-based Mach-Zehnder modulator (MZM) employing quantum-confined Stark effect (QCSE) for operation around 2000 nm. The polarization sensitive device is based on 15 compressively strained quantum wells and achieves an electro-optic (EO) bandwidth of at least 9 GHz, with a DC extinction ratio of ~9 dB, and a V(π)L ~9.6 V.mm. We demonstrate back-to-back communication with a 10 Gb/s pseudo-random bit sequence (PRBS) of length 2(7)-1 at a wavelength around 2000 nm.

A randomised phase 2 trial of dexamethasone versus prednisolone in castration-resistant prostate cancer

BACKGROUND

Prednisolone is widely used as secondary hormonal treatment for castration-resistant prostate cancer (CRPC). We hypothesised that dexamethasone, another corticosteroid, is more active.

OBJECTIVE

To compare the activity of prednisolone and dexamethasone in CRPC.

DESIGN, SETTING, AND PARTICIPANTS

This single-centre, randomised, phase 2 trial was performed in 82 men with chemotherapy-naïve CRPC enrolled from 2006 to 2010.

INTERVENTION

Prednisolone 5mg twice daily versus dexamethasone 0.5mg once daily versus intermittent dexamethasone 8mg twice daily on days 1-3 every 3 wk.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The main end point was prostate-specific antigen (PSA) response rate. Secondary end points included time to PSA progression, radiologic response rate using Response Evaluation Criteria In Solid Tumors (RECIST), and safety.

RESULTS AND LIMITATIONS

The intermittent dexamethasone arm was dropped after no response was seen in seven patients. By intention to treat, confirmed PSA response was seen in 41% versus 22% for daily dexamethasone versus prednisolone, respectively (p=0.08). In evaluable patients, the PSA response rates were 47% versus 24% for dexamethasone and prednisolone, respectively (p=0.05). Median time to PSA progression was 9.7 mo on dexamethasone versus 5.1 mo on prednisolone (hazard ratio: 1.6; 95% confidence interval, 0.9-2.8). In 43 patients with measurable disease, the response rate by RECIST was 15% and 6% for dexamethasone and prednisolone, respectively (p=0.6). Of 23 patients who crossed over at PSA progression on prednisolone, 7 of the 19 evaluable (37%) had a confirmed PSA response to dexamethasone. Clinically significant toxicities were rare.

CONCLUSIONS

Dexamethasone may be more active than prednisolone in CRPC. In the absence of more definitive trials, dexamethasone should be used in preference to prednisolone.

PATIENT SUMMARY

We compared two different steroids used for treating men with advanced prostate cancer. Our results suggest that dexamethasone may be more effective than prednisolone and that both are well tolerated.

CLINICAL TRIAL REGISTRY

EUDRAC 2005-006018-16.

Prospective phase 1 study assessing feasibility of IMRT and IGART to deliver simultaneous integrated high-dose tumor boost (up to 70 Gy) for the radical treatment of localized muscle-invasive bladder cancer

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Background: Advances in IGART offer individualized solutions to improve target coverage and reduce normal tissue irradiation allowing opportunity to increase radiation tumour dose and spare normal bladder. Methods: A library of 3 IMRT plans were created (small, medium and large) from planning CT scans performed at 30 and 60 minutes; treating whole bladder to 52 Gy and tumour to 70 Gy in 32 fractions. Where normal tissue dose constraints were not met consideration was made to boosting tumour to lower dose (68 Gy-64 Gy). Cone beam CT (CBCT) imaging was performed prior to each fraction. Appropriate PTV was selected from the library for treatment delivery. Post treatment CBCT was acquired weekly in order to assess intra-fraction filling and coverage. Results: 22 patients have been planned using this technique. All have met tissue constraints for treatment to 70 Gy. 21 patients have completed radiotherapy, 18 completed treatment to 70 Gy; 1 patient was planned and treated to 68 Gy prior to dose escalation using this technique; 1 patient was treated to a total dose of 65.6 Gy because dose limiting toxicity occurred before dose escalation. 572 CBCTs have been evaluated. Treatment was delivered using small, medium, and large plans in 35%, 52%, and 13% cases respectively. Mean intra-fraction filling was 14 cm3 (SD 16.3, range 0.23-107.9). Mean time between pre- and post-CBCTs was 13 min (SD 2.1, range 9-18). Mean D 98% as assessed on post-radiotherapy CBCT was 98.7% (SD 1.78, range 89.9-100%). At median follow-up of 8 months (range 1-24 months), 18 patients remain alive and disease free. 2 superficial recurrences and 3 deaths from metastatic bladder cancer have occurred. No muscle invasive recurrences have occurred within this cohort. Using this technique one patient has experienced late toxicity (grade 3 cystitis) 5.3 months after radiotherapy (now resolved). Conclusions: IGART using IMRT to delivery a simultaneous integrated tumour boost is feasible with acceptable toxicity. Trial recruitment continues at 70 Gy and will be evaluated in a randomised trial (RAIDER). Clinical trial information: NCT01124682.

Comparing the microbial risks associated with household drinking water supplies used in peri-urban communities of Phnom Penh, Cambodia

Most Cambodians lack access to a safe source of drinking water. Piped distribution systems are typically limited to major urban centers in Cambodia, and the remaining population relies on a variety of surface, rain, and groundwater sources. This study examines the household water supplies available to Phnom Penh's resettled peri-urban residents through a case-study approach of two communities. A quantitative microbial risk assessment is performed to assess the level of diarrheal disease risk faced by community members due to microbial contamination of drinking water. Risk levels found in this study exceed those associated with households consuming piped water. Filtered and boiled rain and tank water stored in a kettle, bucket/cooler, bucket with spigot or a 500 mL bottle were found to provide risk levels within one order-of-magnitude to the piped water available in Phnom Penh. Two primary concerns identified are the negation of the risk reductions gained by boiling due to prevailing poor storage practices and the use of highly contaminated source water.

Retinopathy of prematurity: Risk factors and variability in Canadian neonatal intensive care units

OBJECTIVE

To identify predictors of severe retinopathy of prematurity (ROP) in a large population-based cohort and to examine risk-adjusted variations across units.

STUDY DESIGN

Retrospective analysis of Canadian Neonatal Network data on neonates with birth weight <1500 g who were screened for ROP between 2003 and 2010. Characteristics of infants with and without ROP were compared and a risk-adjusted model for severe ROP was developed. Rates of severe ROP were compared between sites.

RESULTS

1163 of 9187 (12.7%) infants developed severe ROP. Lower gestational age, male sex, small for gestational age, patent ductus arteriosus, late onset sepsis, more than two blood transfusions, inotrope use, and outborn status were associated with an increased risk of severe ROP. Severe ROP rates varied significantly between units.

CONCLUSION

Younger, smaller and sicker male infants had higher adjusted risks of severe ROP and rates varied significantly among sites.

Investigating the influence of flip angle and k-space sampling on dynamic contrast-enhanced MRI breast examinations

RATIONALE AND OBJECTIVES

To retrospectively investigate the effect of flip angle (FA) and k-space sampling on the performance of dynamic contrast-enhanced (DCE-) magnetic resonance imaging (MRI) breast sequences.

MATERIALS AND METHODS

Five DCE-MRI breast sequences were evaluated (10°, 14°, and 18° FAs; radial or linear k-space sampling), with 7-10 patients in each group (n = 45). All sequences were compliant with current technical breast screening guidelines. Contrast agent (CA) uptake curves were constructed from the right mammary artery for each examination. Maximum relative enhancement, E(max), and time-to-peak enhancement, T(max), were measured and compared between protocols (analysis of variance and Mann-Whitney). For each sequence, calculated values of maximum relative enhancement, E(calc), were derived from the Bloch equations and compared to E(max). Fat suppression performance (residual bright fat and chemical shift artifact) was rated for each examination and compared between sequences (Fisher exact tests).

RESULTS

Significant differences were identified between DCE-MRI sequences. E(max) increased significantly at higher FAs and with linear k-space sampling (P < .0001; P = .001). Radial protocols exhibited greater T(max) than linear protocols at FAs of both 14° (P = .025) and 18° (P < .0001), suggesting artificially flattened uptake curves. Good correlation was observed between E(calc) and E(max) (r = 0.86). Fat suppression failure was more pronounced at an FA of 18° (P = .008).

CONCLUSIONS

This retrospective approach is validated as a tool to compare and optimize breast DCE-MRI sequences. Alterations in FA and k-space sampling result in significant differences in CA uptake curve shape which could potentially affect diagnostic interpretation. These results emphasize the need for careful parameter selection and greater standardization of breast DCE-MRI sequences.

A randomized clinical trial of high-dosage coenzyme Q10 in early Parkinson disease: no evidence of benefit

IMPORTANCE

Coenzyme Q10 (CoQ10), an antioxidant that supports mitochondrial function, has been shown in preclinical Parkinson disease (PD) models to reduce the loss of dopamine neurons, and was safe and well tolerated in early-phase human studies. A previous phase II study suggested possible clinical benefit.

OBJECTIVE

To examine whether CoQ10 could slow disease progression in early PD.

DESIGN, SETTING, AND PARTICIPANTS

A phase III randomized, placebo-controlled, double-blind clinical trial at 67 North American sites consisting of participants 30 years of age or older who received a diagnosis of PD within 5 years and who had the following inclusion criteria: the presence of a rest tremor, bradykinesia, and rigidity; a modified Hoehn and Yahr stage of 2.5 or less; and no anticipated need for dopaminergic therapy within 3 months. Exclusion criteria included the use of any PD medication within 60 days, the use of any symptomatic PD medication for more than 90 days, atypical or drug-induced parkinsonism, a Unified Parkinson's Disease Rating Scale (UPDRS) rest tremor score of 3 or greater for any limb, a Mini-Mental State Examination score of 25 or less, a history of stroke, the use of certain supplements, and substantial recent exposure to CoQ10. Of 696 participants screened, 78 were found to be ineligible, and 18 declined participation.

INTERVENTIONS

The remaining 600 participants were randomly assigned to receive placebo, 1200 mg/d of CoQ10, or 2400 mg/d of CoQ10; all participants received 1200 IU/d of vitamin E.

MAIN OUTCOMES AND MEASURES

Participants were observed for 16 months or until a disability requiring dopaminergic treatment. The prospectively defined primary outcome measure was the change in total UPDRS score (Parts I-III) from baseline to final visit. The study was powered to detect a 3-point difference between an active treatment and placebo.

RESULTS

The baseline characteristics of the participants were well balanced, the mean age was 62.5 years, 66% of participants were male, and the mean baseline total UPDRS score was 22.7. A total of 267 participants required treatment (94 received placebo, 87 received 1200 mg/d of CoQ10, and 86 received 2400 mg/d of CoQ10), and 65 participants (29 who received placebo, 19 who received 1200 mg/d of CoQ10, and 17 who received 2400 mg/d of CoQ10) withdrew prematurely. Treatments were well tolerated with no safety concerns. The study was terminated after a prespecified futility criterion was reached. At study termination, both active treatment groups showed slight adverse trends relative to placebo. Adjusted mean changes (worsening) in total UPDRS scores from baseline to final visit were 6.9 points (placebo), 7.5 points (1200 mg/d of CoQ10; P = .49 relative to placebo), and 8.0 points (2400 mg/d of CoQ10; P = .21 relative to placebo).

CONCLUSIONS AND RELEVANCE

Coenzyme Q10 was safe and well tolerated in this population, but showed no evidence of clinical benefit.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00740714.

Chromosomal location of blaCTX-M genes in clinical isolates of Escherichia coli from Germany, The Netherlands and the UK

This study aimed to detect and characterise clinical Escherichia coli isolates suspected of carrying chromosomally encoded CTX-M enzymes. Escherichia coli (n=356) obtained in Germany, The Netherlands and the UK (2005-2009) and resistant to third-generation cephalosporins were analysed for the presence of ESBL-/AmpC-encoding genes within the European SAFEFOODERA-ESBL project. β-Lactamases and their association with IS26 and ISEcp1 were investigated by PCR. Isolates were typed by phylogenetic grouping, MLST and PFGE. Plasmids were visualised by S1 nuclease PFGE, and the location of blaCTX-M genes was determined by Southern hybridisation of XbaI-, S1- and I-CeuI-digested DNA. ESBL enzymes could not be located on plasmids in 17/356 isolates (4.8%). These 17 isolates, from different countries and years, were ascribed to phylogenetic groups D (9), B2 (6) and B1 (2), and to seven sequence types, with ST38 being the most frequent (7 phylogroup D isolates). Eleven isolates produced CTX-M-15. blaCTX-M-15 genes were associated with ISEcp1. The remaining isolates expressed the CTX-M group 9 β-lactamases CTX-M-14 (4), CTX-M-9 (1) and CTX-M-51 (1). blaCTX-M probes hybridised with I-CeuI- and/or XbaI-digested DNA, but not with S1-digested DNA, corroborating their chromosomal location. To summarise, only 4.8% of a large collection of ESBL-producing E. coli isolates harboured chromosomal blaCTX-M genes. These isolates were of human origin and belonged predominantly to ST38 and ST131, which possibly indicates the role of these sequence types in this phenomenon. However, heterogeneity among isolates was found, suggesting that their spread is not only due to the dispersion of successful E. coli clones.

Experiences and attitudes towards evidence-informed policy-making among research and policy stakeholders in the Canadian agri-food public health sector

Policy-makers working at the interface of agri-food and public health often deal with complex and cross-cutting issues that have broad health impacts and socio-economic implications. They have a responsibility to ensure that policy-making based on these issues is accountable and informed by the best available scientific evidence. We conducted a qualitative descriptive study of agri-food public health policy-makers and research and policy analysts in Ontario, Canada, to understand their perspectives on how the policy-making process is currently informed by scientific evidence and how to facilitate this process. Five focus groups of 3-7 participants and five-one-to-one interviews were held in 2012 with participants from federal and provincial government departments and industry organizations in the agri-food public health sector. We conducted a thematic analysis of the focus group and interview transcripts to identify overarching themes. Participants indicated that the following six key principles are necessary to enable and demonstrate evidence-informed policy-making (EIPM) in this sector: (i) establish and clarify the policy objectives and context; (ii) support policy-making with credible scientific evidence from different sources; (iii) integrate scientific evidence with other diverse policy inputs (e.g. economics, local applicability and stakeholder interests); (iv) ensure that scientific evidence is communicated by research and policy stakeholders in relevant and user-friendly formats; (V) create and foster interdisciplinary relationships and networks across research and policy communities; and (VI) enhance organizational capacity and individual skills for EIPM. Ongoing and planned efforts in these areas, a supportive culture, and additional education and training in both research and policy realms are important to facilitate evidence-informed policy-making in this sector. Future research should explore these findings further in other countries and contexts.

Phase I dose-escalated image-guided adaptive bladder radiotherapy study: Results of first dose cohort (68Gy)

291

Background: Prospective study assessing the safety of dose escalation in the treatment of localised muscle-invasive bladder cancer using image-guided adaptive radiotherapy (RT) with a reduced high-dose tumour volume. Methods: Radical RT was planned and delivered in 3 phases. Phase I was delivered to the empty whole bladder (10Gy 5#). Bladder variation assessed on phase I daily imaging was used to determine the adaptive approach for phase III (composite volume or plan of the day). Phase II was delivered to a tumour boost volume on a partially filled bladder (18Gy 9# if normal tissue dose-constraints were met, or to 14Gy 7# if they were not). The adaptive phase III (40Gy 20#) was delivered to the empty whole bladder. The primary endpoint was late RTOG toxicity. Results: Of the twenty-six patients recruited to 68Gy, 20 patients met the normal tissue constraints for dose escalation. For the phase III adaptive technique, 14 patients were treated with a composite volume approach and 12 with a plan of the day. At median follow-up of 24 months, 13 (65%) dose escalated patients remain alive and disease free. Within this dose cohort there has been 1 muscle invasive local recurrence, 1 superficial recurrence and 1 patient has developed metastases. 5 patients in the dose-escalated group have died; 3 from cardiac events, 1 from hospital acquired pneumonia and 1 from metastatic bladder cancer. 1 patient in the dose-escalated group has experienced grade 3 late toxicity (cystitis) occurring 24.6 months after the end of radiotherapy. Conclusions: Image-guided adaptive RT techniques with reduced high-dose volume allow tumour dose-escalation. Toxicity data to date suggest tolerability of 68Gy. Local disease control rates are promising. Trial recruitment continues at 70Gy using intensity modulated radiotherapy technique to deliver a simultaneous integrated boost. Clinical trial information: 7653.

Evaluation of the prostate health index (phi) as a novel biomarker in active surveillance of prostate cancer

81

Background: Phi is calculated from serum PSA, free/total (f/t) PSA and [-2]proPSA using the Beckman Coulter assay kit, and has been approved for use in patient selection for diagnostic prostate biopsy. We hypothesized that phi might also predict outcome of active surveillance. Methods: From 2002, we have done a prospective cohort study of active surveillance for men with T1/2, Gleason <= 3+4, PSA < 15ng/ml prostate cancer. Serum was banked at baseline. Monitoring included 6 monthly PSA and 2-yearly repeat biopsy. Treatment was indicated for PSA velocity > 1ng/ml/yr or Gleason >= 4+3 on repeat biopsy. We analyzed baseline phi with respect to time to treatment. A multivariate model was fitted using total PSA, PSA velocity, PSA density, Gleason score, % biopsy cores positive, T stage, and maximum % cancer in any biopsy core. The fit of this model was then compared with the addition of % f/t PSA and phi. Results: 370 patients were evaluable with a median follow-up of 5 years. The table shows the association between baseline phiand time to treatment. On multivariate analysis, the model with % f/t PSA was a significant improvement over base model (change in fit 41.1, p<0.001), and the model with % f/t PSA and phi was a significantly better fit than % f/t PSA alone (change in fit 11.1, p=0.001). Conclusions: In men with favorable risk prostate cancer, phi at diagnosis was a significant predictor of the outcome of active surveillance. The data require validation, but suggest that active surveillance is particularly attractive to men with a low phi. [Table: see text]

Catalytic activation of OKO zeolite with intersecting pores of 10- and 12-membered rings using atomic layer deposition of aluminium

Atomic layer deposition of aluminium transforms the all-silica interrupted -COK-14 zeolite into an acid catalyst with a fully connected OKO framework.