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Dive into the research topics where M.V. Williams is active.

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Featured researches published by M.V. Williams.


Clinical Oncology | 2009

Geographical Variation in Radiotherapy Services Across the UK in 2007 and the Effect of Deprivation

M.V. Williams; K. Drinkwater

AIMSnModelling of demand has shown substantial underprovision of radiotherapy in the UK. We used national audit data to study geographical differences in radiotherapy waiting times, access and dose fractionation across the four countries of the UK and between English strategic health authorities.nnnMATERIALS AND METHODSnWe used a web-based tool to collect data on diagnosis, dose fractionation and waiting times on all National Health Service patients in the UK starting a course of radiotherapy in the week commencing 24 September 2007. Cancer incidence for the four countries of the UK and for England by primary care trust was used to model demand for radiotherapy aggregated by country and by strategic health authority.nnnRESULTSnAcross the UK, excluding skin cancer, 2504 patients were prescribed 33 454 fractions in the audit week. Waits for radical radiotherapy exceeded the recommended 4 week maximum for 31% of patients (range 0-62%). Fractions per million per year ranged from 17 678 to 36 426 and radical fractions per incident cancer ranged from 3.0 to 6.7. Patients who were treated received similar treatment in terms of fractions per radical course of radiotherapy (18.2-23.0). Access rates ranged from 25.2 to 48.8%, nearing the modelled optimum of 50.7% in three regions. Fractions per million prescribed as a first course of treatment varied from 43.9 to 90.3% of modelled demand. The percentage of patients failing to meet the 4 week Joint Council for Clinical Oncology target for radical radiotherapy rose as activity rates increased (r=0.834), indicating a mismatch of demand and capacity. In England, a comparison between strategic health authorities showed that increasing deprivation was correlated with lower rates of access to radiotherapy (r=-0.820).nnnCONCLUSIONSnThere are substantial differences across the UK in the radiotherapy provided to patients and its timeliness. Radiotherapy capacity does not reflect regional variations in cancer incidence across the UK (3618-5800 cases per million per year). In addition, deprivation is a major unrecognised influence on radiotherapy access rates. In regions with higher levels of deprivation, fewer patients with cancer receive radiotherapy and the proportion treated radically is lower. This probably reflects late presentation with advanced disease, poor performance status and co-morbid illness. To provide an equitable, evidence-based service, the needs of the local population should be assessed using demand modelling based on local cancer incidence. Ideally this should include data on deprivation, performance status and stage at presentation. The results should be compared with local radiotherapy activity data to understand waits, access and dose fractionation in order to plan adequate provision for the future. The development of a mandatory radiotherapy data set in England will facilitate this, but to assist change it is essential that the results are analysed and fed back to clinicians and commissioners.


Clinical Oncology | 2009

Radiotherapy in England in 2007: Modelled Demand and Audited Activity

M.V. Williams; K. Drinkwater

AIMSnModelling of demand has indicated substantial underprovision of radiotherapy in England. We have used national audit data to understand the differences between theory and practice.nnnMATERIALS AND METHODSnWe used a web-based tool to collect data on all National Health Service patients in England starting a course of radiotherapy in the week commencing 24 September 2007. We also collected information on cancer site, so that patients could be triaged into the 22 categories used by the National Radiotherapy Advisory Group (NRAG).nnnRESULTSnIn England, excluding skin cancer other than melanoma, 2114 patients were prescribed 27,420 fractions during that week. Comparison of the audit data with the NRAG model showed that the shortfall in provision was a mixture of a lack of access (67%) and reduced fractionation (33%). The largest contributions to the overall gap were seen in the treatment of cancers of the breast (6%) (modelled at 15 fractions), head and neck (10%), lung (28%) and prostate (14%), together accounting for 58% of the difference. Others (including sarcoma and unknown primary) accounted for 19% of the difference. Limited access to radiotherapy for patients with stomach and pancreatic cancer contributed 10% and reduced fractionation for oesophageal cancer accounted for 6% of the overall gap. Fewer patients than expected were treated for rectal cancer, but they received 25 fraction regimens rather than short-course preoperative treatment. Patients with leukaemia and cancers of the brain, colon, corpus uteri and ovary received radiotherapy more often than expected, but because they are relatively rare none of these had an overall impact exceeding 1.2% of the gap in provision.nnnCONCLUSIONSnThis audit confirms the underprovision of radiotherapy in England and shows that it is largely accounted for by low access rates of 37% rather than the 50% accepted in the literature. In consequence we estimate that 33 881 patients (13.9%) of the 243 748 patients diagnosed with cancer in England during 2006/2007 did not receive the radiotherapy we would have expected. Some of this gap in provision may be accounted for by differences in stage and performance status, which limit treatment options, for example in lung cancer. The NRAG model should be updated to take account of new data from this and other national audits, to ensure that it describes the stage and performance status of English patients and is sensitive to the range of professional opinion about treatment options. This will be essential for long-term planning as cancer incidence increases over the next decade, but it does not weaken the conclusion that there is a substantial current shortfall to be addressed immediately to improve timely access to treatment and thus the outcomes of therapy. As more resource becomes available, it should be possible to consider changing dose fractionation to comply with evidence-based practice and national guidelines from the National Institute for Health and Clinical Excellence and other bodies without disadvantaging patients by increasing waiting times.


Clinical Oncology | 2010

The Implementation of Intensity-modulated Radiotherapy in the UK

M.V. Williams; T. Cooper; R. Mackay; John Nicholas Staffurth; D. Routsis; N.G. Burnet

Radiotherapy in the UK lags behind that in much of Europe in terms of both the low proportion of cancer patients gaining access to treatment and the long waiting times [1] and [2]. The technical quality of radiotherapy is also a cause for concern. The National Radiotherapy Advisory Group (NRAG) report published in May 2007 had an overall aim of developing world class radiotherapy [3]. The NRAG technology subgroup report envisaged that within 10 years 50% of patients would be treated by four-dimensional image-guided, adaptive radiotherapy, of which intensity-modulated radiotherapy [IMRT] is a vital component [4]. This paper summarises the work of the National Radiotherapy Implementation Group (NRIG) in supporting the implementation of IMRT.


Clinical Oncology | 2012

The Management of Lung Cancer: A UK Survey of Oncologists

S.L. Prewett; S. Aslam; M.V. Williams; David Gilligan

AIMSnThis report reviews current radiotherapy practice across the UK in the management of lung cancer, and the way new treatments and technologies are being introduced, where improvements have occurred, and where work is still required. We wanted to determine adherence to both National Radiotherapy Advisory Group and National Institute for Health and Clinical Excellence (NICE) guidance. This survey was conducted on behalf of the Department of Health Lung Cancer & Mesothelioma Advisory Group.nnnMATERIALS AND METHODSnWe sent a questionnaire to all UK radiotherapy departments. It covered radical radiotherapy dose fractionation, the use of concurrent or sequential chemotherapy for both non-small cell and small cell lung cancers, the use of continuous hyperfractionated accelerated radiotherapy, new radiotherapy techniques, the use of positron emission tomography/computed tomography for planning purposes and patient accrual into current National Cancer Research Network UK trials.nnnRESULTSnThis UK-wide survey of radiotherapy practice for lung cancer showed broad compliance with NICE clinical guidance, but highlighted significant variation in fractionation schedules and the use of concomitant chemoradiotherapy. Clinical trial entry into lung cancer radiotherapy trials was variable and many centres are not fully participating in recruitment into these trials.nnnCONCLUSIONSnThis report has shown the variability of radiotherapy provision nationally. Current practice is largely consistent with current and updated NICE recommendations and best practice and should be recognised as such. It has also highlighted areas where improvements are still needed, particularly fractionation and new technologies. One particular aspect of concern is the poor recruitment to current UK-based clinical trials in lung cancer.


Clinical Oncology | 1990

Problems in the management of testicular seminoma associated with a horseshoe kidney.

S.A.G. Elyan; D.H. Reed; M.J. Ostrowski; M.V. Williams; Adrian K. Dixon

Four patients with seminoma of the testis and coexisting horseshoe kidney are presented. Three patients had stage one disease, which would conventionally be managed by abdominal nodal irradiation. However, because of the risk of radiation nephritis, a surveillance policy was adopted with regular computed tomography (CT). Two of these three patients have relapsed and are disease free after chemotherapy. The fourth patient had Stage IIC disease which initially responded to combined radiotherapy and chemotherapy. This patients disease relapsed and he died despite further treatment. Because of the altered retroperitoneal anatomy, CT interpretation must be made with special care.


Clinical Oncology | 2012

Progress with Intensity-modulated Radiotherapy Implementation in the UK

W. P. M. Mayles; T. Cooper; R. Mackay; John Nicholas Staffurth; M.V. Williams

The evidence for the benefits of intensity-modulated radiotherapy (IMRT) in reducing toxicity [1e6] and allowing safe dose escalation with an expectation of improved cure rates [1,7] is rapidly growing. Two previous surveys [8,9] of the availability of inverse planned IMRT in the UK showed slow uptake of this advanced form of radiotherapy, resulting in unequal access, with only 2% of patients being treated in 2008. In England, the National Radiotherapy Implementation Group set out to increase this number, as described by Cooper and Williams in a separate editorial [10]. A target of achieving 33% of radical radiotherapy patients being treated with IMRT was set. The 33% target comprised 9% being treated with forward planned IMRT for breast cancer, with the remaining 24% being inverse planned treatments to other body sites. A review of these recommendations carried out in November 2011 reiterated these figures. This would compare with up to 50% of patients reportedly being treated with IMRT in the USA and in private centres in the UK [11], although the figures for private centres may not be entirely comparable because of the different case mix.


Clinical Oncology | 2013

The Malthus Programme: Developing Radiotherapy Demand Models for Breast and Prostate Cancer at the Local, Regional and National Level

C. Round; T. Mee; N.F. Kirkby; T. Cooper; M.V. Williams; R. Jena

AIMSnThe Malthus Programme has delivered a tool for modelling radiotherapy demand in England. The model is capable of simulating demand at the local level. This article investigates the local and regional level variation in predicted demand with respect to Breast and Prostate cancer, the two tumour types responsible for the majority of radiotherapy treatment workload in England.nnnMATERIALS AND METHODSnSimulations were performed using the Malthus model, using base population incidence data for the period from 2007-2009. Simulations were carried out at the level of Primary Care Trusts, Cancer Networks, and nationwide, with annual projections for 2012, 2016 and 2020. Benchmarking was undertaken against previously published models from the UK, Canada and Australia.nnnRESULTSnFor breast cancer, the fraction burden for 2012 varied from 5537 fractions per million in Tower Hamlets PCT to 18 896 fractions per million in Devon PCT (national mean - 13 592 fractions per million). For prostate cancer, the fraction burden for 2012 varied from 4874 fractions per million in Tower Hamlets PCT to 23 181 fractions per million in Lincolnshire PCT (national mean - 15 087 fractions per million). Predictions of population growth by age cohort for 2016 and 2020 result in the regional differences in radiotherapy demand becoming greater over time. Similar effects were also observed at the level of the cancer network.nnnCONCLUSIONSnOur model shows the importance of local population demographics and cancer incidence rates when commissioning radiotherapy services.


Clinical Oncology | 2003

Lessons Learned from Raltitrexed – Quality Assurance, Patient Education and Intensive Supportive Drugs to Optimise Tolerability

R.J Thomas; M.V. Williams; J Garcia-Vargas

Although recent trials have raised concerns about the toxicity of raltitrexed monotherapy in patients with advanced colorectal cancer (aCRC), similar concerns have also been raised with other chemotherapy regimens in aCRC. The lessons learnt form our previous experiences with raltitrexed are, therefore, still important as they offer practical guidances to optimise tolerability of chemotherapy for CRC in general. The aims of the study were to report the low-toxicity profile in 58 patients receiving raltitrexed when a rigorous patient information and education strategy was implemented together with an intensive supportive adjuvant drugs regimen from the start. After a discussion with the consultant, all patients received a further consultation with a specialist nurse, a series of bespoke information tools, including an information video and written guidelines on how to avoid, prevent and deal promptly with the side-effects of raltitrexed. They all received intravenous adjuvant ondansetron and dexamethasone, then oral domperidone, ranitidine and nystatin from cycle one. The dose intensity was 98% over 307 cycles. Toxicity associated with raltitrexed comprised grade 1/2 diarrhoea (31.6% of treatment cycles), nausea (12.4%) and vomiting (8.4%), with no grade 3/4 events; grade 1/2 alopecia (17.9%); grade 1 (only) stomatitis (2.3%) and grade 1/2/3 lethargy (70.3%, only 2.3% grade 3), anaemia (14.3%, only 0.3% grade 3) and neutropenia (3.3%, only 0.3% grade 3). There were no treatment-related deaths. The low toxicity, despite high-dose intensity, suggests that intensive supportive education and drugs should have a role in the future design of regimens containing raltitrexed and other chemotherapy regimens for colorectal carcinoma.


Clinical Oncology | 2015

Quantifying uncertainty in radiotherapy demand at the local and national level using the Malthus model.

R. Jena; T. Mee; N.F. Kirkby; M.V. Williams

The Malthus programme produces a model for the local and national level of radiotherapy demand for use by commissioners and radiotherapy service leads in England. The accuracy of simulation is dependent on the population cancer incidence, stage distribution and clinical decision data used by the model. In order to quantify uncertainty in the model, a global sensitivity analysis of the Malthus model was undertaken. As predicted, key decision points in the model relating to stage distribution and indications for surgical or non-surgical initial management of disease were observed to yield the strongest effect on simulated radiotherapy demand. The proportion of non-small cell lung cancer patients presenting with stage IIIB/IV disease had the largest effect on fraction burden in the four most common cancer types treated with radiotherapy, where a 1% change in stage IIIb/IV disease yielded a 1.3% change in fraction burden for lung cancer patients. A 1% change in mastectomy rate yielded a 0.37% change in fraction burden for breast cancer patients. The model is also highly sensitive to changes in the radiotherapy indications in colon and gastric cancer. Broadly, the findings of the sensitivity analysis mirror those previously published by other groups. Sensitivity analysis of the local-level population and cancer incidence data revealed that the cancer registration rate in the 50-64 year female population had the highest effect on simulation results. The analysis reveals where additional effort should be undertaken to provide accurate estimates of important parameters used in radiotherapy demand models.


Clinical Oncology | 2017

Highly Conformal Craniospinal Radiotherapy Techniques Can Underdose the Cranial Clinical Target Volume if Leptomeningeal Extension through Skull Base Exit Foramina is not Contoured

D.J. Noble; T. Ajithkumar; J Lambert; I Gleeson; M.V. Williams; S.J. Jefferies

Aims Craniospinal irradiation (CSI) remains a crucial treatment for patients with medulloblastoma. There is uncertainty about how to manage meningeal surfaces and cerebrospinal fluid (CSF) that follows cranial nerves exiting skull base foramina. The purpose of this study was to assess plan quality and dose coverage of posterior cranial fossa foramina with both photon and proton therapy. Materials and methods We analysed the radiotherapy plans of seven patients treated with CSI for medulloblastoma and primitive neuro-ectodermal tumours and three with ependymoma (total n = 10). Four had been treated with a field-based technique and six with TomoTherapy™. The internal acoustic meatus (IAM), jugular foramen (JF) and hypoglossal canal (HC) were contoured and added to the original treatment clinical target volume (Plan_CTV) to create a Test_CTV. This was grown to a test planning target volume (Test_PTV) for comparison with a Plan_PTV. Using Plan_CTV and Plan_PTV, proton plans were generated for all 10 cases. The following dosimetry data were recorded: conformity (dice similarity coefficient) and homogeneity index (D2 − D98/D50) as well as median and maximum dose (D2%) to Plan_PTV, V95% and minimum dose (D99.9%) to Plan_CTV and Test_CTV and Plan_PTV and Test_PTV, V95% and minimum dose (D98%) to foramina PTVs. Results Proton and TomoTherapy™ plans were more conformal (0.87, 0.86) and homogeneous (0.07, 0.04) than field-photon plans (0.79, 0.17). However, field-photon plans covered the IAM, JF and HC PTVs better than proton plans (P = 0.002, 0.004, 0.003, respectively). TomoTherapy™ plans covered the IAM and JF better than proton plans (P = 0.000, 0.002, respectively) but the result for the HC was not significant. Adding foramen CTVs/PTVs made no difference for field plans. The mean Dmin dropped 3.4% from Plan_PTV to Test_PTV for TomoTherapy™ (not significant) and 14.8% for protons (P = 0.001). Conclusions Highly conformal CSI techniques may underdose meninges and CSF in the dural reflections of posterior fossa cranial nerves unless these structures are specifically included in the CTV.

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Dive into the M.V. Williams's collaboration.

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K. Drinkwater

Royal College of Radiologists

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R. Jena

University of Cambridge

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T. Mee

University of Surrey

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C. Round

University of Cambridge

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D. Routsis

University of Cambridge

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D.H. Reed

University of Cambridge

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D.J. Noble

University of Cambridge

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