MICRODOSIMETRIC APPLICATIONS IN PROTON AND HEAVY ION THERAPY USING SILICON MICRODOSIMETERS

Using the CMRP 'bridge' μ+ probe, microdosimetric measurements were undertaken out-of-field using a therapeutic scanning proton pencil beam and in-field using a 12C ion therapy field. These measurements were undertaken at Mayo Clinic, Rochester, USA and at HIMAC, Chiba, Japan, respectively. For a typical proton field used in the treatment of deep-seated tumors, we observed dose-equivalent values ranging from 0.62 to 0.99 mSv/Gy at locations downstream of the distal edge. Lateral measurements at depths close to the entrance and along the SOBP plateau were found to reach maximum values of 3.1 mSv/Gy and 5.3 mSv/Gy at 10 mm from the field edge, respectively, and decreased to ~0.04 mSv/Gy 120 mm from the field edge. The ability to measure the dose-equivalent with high spatial resolution is particularly relevant to healthy tissue dose calculations in hadron therapy treatments. We have also shown qualitatively and quantitively the effects critical organ motion would have in treatment using microdosimetric spectra. Large differences in spectra and RBE10 were observed for treatments where miscalculations of 12C ion range would result in critical structures being irradiated, showing the importance of motion management.

Correlation between gonial angle and dynamic tongue collapse in children with snoring/sleep disordered breathing - an exploratory pilot study

BACKGROUND

Drug induced sleep endoscopy (DISE) is hoped to identify reasons of failure of adenotonsillectomy (AT) in treating pediatric sleep disordered breathing (SDB). Maxillomandibular disproportion has been studied as another association which may explain alternative pathogenesis of SDB. We aimed to explore the relation between the size of the gonial angle and inclination of the epiglottis measured from cone beam CT (CBCT) and tongue base collapse based on DISE in children with SDB.

METHOD

A retrospective chart review was conducted at a tertiary pediatric center. Children (6-17 years old) assessed at a multi-disciplinary Upper Airway Clinic, diagnosed with SDB and maxillo-mandibular disproportion (MMD), and who underwent DISE were eligible. Variables obtained from the electronic medical records of the clinic and prospective database included demographics, comorbidities, surgeries performed, investigations, DISE findings and CBCT findings. The gonial angle of subjects with and without tongue base collapse (TBC) on SNP were compared.

RESULTS

In total 29 patients (13 male, 8 female) age 6-17 (median= 9) were eligible for the study from January 2009 - July 2016. We included 11 subjects, and 10 comparators. The mean gonial angle of the TBC group was 139.3°± 7.6°, while that of the comparison group was 129.4°±3.5 (mean difference -9.937, 95% CI of -15.454 to - 4.421, P = 0.001, power of test 0.95). Additionally, the mean inclination of the epiglottis had a mild positive correlation (r=0.32, p<0.05) with the gonial angle, in the whole cohort.

CONCLUSIONS

This pilot study suggests that TBC may be mediated by a wider gonial angle in children with SDB patients. The posterior tilt of the epiglottis on CBCT may be a surrogate sign of TBC.

Completing the cervical screening pathway: Factors that facilitate the increase of self-collection uptake among under-screened and never-screened women, an Australian pilot study

Objectives

To examine factors that enhance under-screened and never-screened women's completion of the self-collection alternative pathway of the Renewed National Cervical Screening Program (ncsp) in Victoria, Australia.

Background

With the Australian ncsp changing, starting on 1 December 2017, the Medical Services Advisory Committee (msac) recommended implementing human papillomavirus (hpv) testing using a self-collected sample for under-screened and never-screened populations. In response, a multi-agency group implemented an hpv self-collection pilot project to trial self-collection screening pathways for eligible women.

Methods

Quantitative data were collected on participation rates and compliance rates with follow-up procedures across three primary health care settings. Forty women who self-collected were interviewed in a semi-structured format, and seven agency staff completed in-depth interviews. Qualitative data were used to identify and understand clinical and personal enablers that assisted women to complete self-collection cervical screening pathways successfully.

Results

Eighty-five per cent (10 women) of participants who tested positive for hpv successfully received their results and completed follow-up procedures as required. Two remaining participants also received hpv-positive results. However, agencies were unable to engage them in follow-up services and procedures. The overall participation rate in screening (self-collection or Pap test) was 85.7% (84 women), with 79 women self-collecting. Qualitative data indicated that clear explanations on self-collection, development of trusting, empathetic relationships with health professionals, and recognition of participants' past experiences were critical to the successful completion of the self-collection pathway. When asked about possible inhibitors to screening and to following up on results and appointments, women cited poor physical and mental health, as well as financial and other structural barriers.

Conclusion

A well-implemented process, led by trusted, knowledgeable, and engaged health care professionals who can provide appropriate support and information, can assist under-screened and never-screened women to complete the hpv self-collection pathway successfully.

Self-collection for under-screened women in a National Cervical Screening Program: pilot study

BACKGROUND

Commencing 1 December 2017, Australia introduced human papillomavirus (hpv)-based cervical screening. As part of this Australian renewed National Cervical Screening Program (ncsp) women who are either never- or under-screened and who refuse a practitioner collected sample will be able to collect their own sample for cervical screening. The aim of this study is to examine the quantitative results of a pilot study into the acceptability of the self-collection alternative pathway.

METHODS

Eligible participants were offered the opportunity to collect their own sample. Those who agreed were given a flocked swab and an instruction sheet and took their own sample in an area of the health care clinic that afforded them adequate privacy. These samples were then given to clinic staff who returned them to Victorian Cytology Service (vcs) Pathology for hpv nucleic acid testing.

RESULTS

Of 98 eligible women, seventy-nine undertook self-collection for hpv-based cervical screening. Seventy-seven produced valid results, 14 were positive for oncogenic hpv, with 10 undertaking follow-up. Three women were found to have cervical squamous abnormalities with two of those being high-grade intraepithelial squamous lesions.

CONCLUSION

The pilot study for self-collection for cervical screening produced quantitative data that were similar to that already reported in the literature, but had a much higher rate of acceptance compared with self-collection programs based in the home.

Utilisation of anti-TNF levels in a UK tertiary IBD centre

OBJECTIVE

To ascertain how anti-tumour necrosis factor (TNF) drug and anti-drug antibody levels testing is used in a 'real-world' setting to optimise inflammatory bowel disease (IBD) treatment.

DESIGN

Retrospective cohort study of prospectively collected patient data.

SETTING

Tertiary IBD centre in London, UK.

PATIENTS

All patients at Guy's and St Thomas' Hospitals on anti-TNF who had levels measured between the start of testing in 2012 and October 2014.

INTERVENTIONS

Anti-TNF drug and anti-drug antibody levels as part of routine monitoring.

MAIN OUTCOME MEASURES

Indication for measuring levels and changes in management made as a result of the levels.

RESULTS

330 infliximab levels were carried out in 199 patients and 143 adalimumab levels were carried out in 103 patients. Levels were primarily done in those with evidence of loss of response; 37% of infliximab levels and 52% of adalimumab levels. Levels resulted in a change in management in 26% of patients in infliximab group and 25% of patients in adalimumab group; however, this was greater in those with loss of response, 62% and 61% respectively. Anti-drug antibodies were detected in 7% of patients.

CONCLUSIONS

Our early experience has demonstrated that measuring anti-TNF drug and anti-drug antibody levels can be useful in the optimisation of IBD management. In an increasing number of patients, particularly those with evidence of loss of response, it allows early decisions to be made regarding changing therapy. It also offers the potential for significant cost-saving by preventing pointless dose escalation in the context of therapeutic levels or when high-level anti-drug antibodies are present.

Condoms and sexual health education as evidence: impact of criminalization of in-call venues and managers on migrant sex workers access to HIV/STI prevention in a Canadian setting

Background

Despite a large body of evidence globally demonstrating that the criminalization of sex workers increases HIV/STI risks, we know far less about the impact of criminalization and policing of managers and in-call establishments on HIV/STI prevention among sex workers, and even less so among migrant sex workers.

Methods

Analysis draws on ethnographic fieldwork and 46 qualitative interviews with migrant sex workers, managers and business owners of in-call sex work venues in Metro Vancouver, Canada.

Results

The criminalization of in-call venues and third parties explicitly limits sex workers’ access to HIV/STI prevention, including manager restrictions on condoms and limited onsite access to sexual health information and HIV/STI testing. With limited labour protections and socio-cultural barriers, criminalization and policing undermine the health and human rights of migrant sex workers working in –call venues.

Conclusions

This research supports growing evidence-based calls for decriminalization of sex work, including the removal of criminal sanctions targeting third parties and in-call venues, alongside programs and policies that better protect the working conditions of migrant sex workers as critical to HIV/STI prevention and human rights.

Percutaneous transcatheter renal embolization with absolute ethanol for uncontrolled nephrotic syndrome: Case reports

Purpose: To retrospectively evaluate renal ethanol embolization in 2 patients with uncontrolled nephrotic syndrome.

Material and Methods: Three kidneys in 2 patients with uncontrolled nephrotic syndrome were embolized with absolute ethanol. The embolization technique, patient outcome and complications were analyzed retrospectively.

Results: The treatment was successful in both patients, with angiography-verified exclusion of blood flow to the renal arteries. Elimination of proteinuria was achieved in both patients and their body weight decreased by 25 and 10 kg, respectively. Hospitalization and protein substitution were no longer needed. No complications occurred.

Conclusion: Permanent bilateral ethanol embolization of the renal arteries is a feasible method of managing a treatment-resistant nephrotic syndrome in selected patients. Non-target embolization can be avoided by using a balloon occlusion catheter.

Centralized medical monitoring in phase III clinical trials: the National Surgical Adjuvant Breast and Bowel Project (NSABP) experience

Background There is a need for data quality assurance procedures in phase III cancer trials. At the National Surgical Adjuvant Breast and Bowel Project (NSABP) ‘real-time’ systems have been developed for quality assurance and study monitoring: (1) manual review and triage of data forms by data managers at the time of submission; (2) computerized edit checking of all submitted data forms; (3) systematic review of eligibility, treatment compliance and toxicity in the first 100 patients of a new protocol; (4) prospective centralized medical review of all reported serious adverse events, treatment failures, second primary cancers and deaths; (5) quarterly review and approval of study summary data files by project statistician; and (6) on-site auditing.

Purpose To assess the utility of an additional final comprehensive review of all patient records to confirm eligibility, disease status and vital status prior to manuscript submission.

Methods Four phase III NSABP studies, which had been monitored using the triagebased quality assurance program described above, were selected for analysis ( n = 7972). Charts for 5965 patients were identified that had not been previously medically reviewed for protocol events of recurrence, second primary cancer or death. Submitted source documents and data forms of these 5965 NSABP patient records underwent medical review to verify patient eligibility, disease status and vital status.

Results This final comprehensive review found no additional treatment failures or deaths, identified seven additional cases of ineligibility, was time-intensive requiring enormous use of expensive resources, and was therefore judged not to add significantly to the integrity of the database.

Limitations Our findings are influenced by the procedures the NSABP employs for quality assurance and study monitoring for Phase III clinical trials and may have limited generalizability to other settings.

Conclusion In the presence of multiple quality assurance and data monitoring systems, the rare discrepancies found between the data forms and source documentation does not support the routine use of a final comprehensive chart review for phase III trials at the NSABP Biostatistical Center.

The measurement of adult blood pressure and management of hypertension before elective surgery: Joint Guidelines from the Association of Anaesthetists of Great Britain and Ireland and the British Hypertension Society

This guideline aims to ensure that patients admitted to hospital for elective surgery are known to have blood pressures below 160 mmHg systolic and 100 mmHg diastolic in primary care. The objective for primary care is to fulfil this criterion before referral to secondary care for elective surgery. The objective for secondary care is to avoid spurious hypertensive measurements. Secondary care should not attempt to diagnose hypertension in patients who are normotensive in primary care. Patients who present to pre-operative assessment clinics without documented primary care blood pressures should proceed to elective surgery if clinic blood pressures are below 180 mmHg systolic and 110 mmHg diastolic.

Genetic Diversity and Protective Efficacy of the RTS,S/AS01 Malaria Vaccine

BACKGROUND

The RTS,S/AS01 vaccine targets the circumsporozoite protein of Plasmodium falciparum and has partial protective efficacy against clinical and severe malaria disease in infants and children. We investigated whether the vaccine efficacy was specific to certain parasite genotypes at the circumsporozoite protein locus.

METHODS

We used polymerase chain reaction-based next-generation sequencing of DNA extracted from samples from 4985 participants to survey circumsporozoite protein polymorphisms. We evaluated the effect that polymorphic positions and haplotypic regions within the circumsporozoite protein had on vaccine efficacy against first episodes of clinical malaria within 1 year after vaccination.

RESULTS

In the per-protocol group of 4577 RTS,S/AS01-vaccinated participants and 2335 control-vaccinated participants who were 5 to 17 months of age, the 1-year cumulative vaccine efficacy was 50.3% (95% confidence interval [CI], 34.6 to 62.3) against clinical malaria in which parasites matched the vaccine in the entire circumsporozoite protein C-terminal (139 infections), as compared with 33.4% (95% CI, 29.3 to 37.2) against mismatched malaria (1951 infections) (P=0.04 for differential vaccine efficacy). The vaccine efficacy based on the hazard ratio was 62.7% (95% CI, 51.6 to 71.3) against matched infections versus 54.2% (95% CI, 49.9 to 58.1) against mismatched infections (P=0.06). In the group of infants 6 to 12 weeks of age, there was no evidence of differential allele-specific vaccine efficacy.

CONCLUSIONS

These results suggest that among children 5 to 17 months of age, the RTS,S vaccine has greater activity against malaria parasites with the matched circumsporozoite protein allele than against mismatched malaria. The overall vaccine efficacy in this age category will depend on the proportion of matched alleles in the local parasite population; in this trial, less than 10% of parasites had matched alleles. (Funded by the National Institutes of Health and others.).