Estimating the Impact of Randomised Control Trial Results on Clinical Practice: Results from a Survey and Modelling Study of Androgen Deprivation Therapy plus Radiotherapy for Locally Advanced Prostate Cancer

Abstract

BackgroundRecent trials have shown that the addition of external beam radiotherapy (EBRT) to androgen deprivation therapy (ADT) improves survival among men with locally advanced prostate cancer.ObjectiveTo examine the potential impact of these trials on changes in clinical practice and life-years saved.Design, setting, and participantsA model was developed to examine the impact of changes in clinical practice in the UK. A survey of clinicians who treat men with prostate cancer in the UK and Canada was performed.MeasurementsOutcomes of interest were the proportion of patients treated with different approaches and the predicted number of life-years saved due to changes in clinical practice. Survey data were cross-tabulated and Pearson's χ2 tests were applied.Results and limitationsThe survey was completed by 193 clinicians (105 from the UK, 80 from Canada), of whom 70% were clinical/radiation oncologists, 8% were medical oncologists, and 15% were urologists. UK respondents were more likely to report a change in practice in response to the results (44% UK vs 21% Canada). Canadians were more likely to have already been using ADT plus radiotherapy (77% Canada vs 56% UK). The increase in the proportion of patients in the UK treated with ADT + EBRT could result in around 3730–5177 extra life-years at 15 yr from a cohort of 7930 men diagnosed in a single calendar year, compared to if all had been treated with ADT alone.ConclusionsTrial findings have changed clinical practice, meaning that men with locally advanced prostate cancer are likely to survive longer.Patient summaryDoctors in the UK have changed practice in response to evidence on the superiority of hormone therapy plus radiotherapy to hormone therapy alone. These changes will improve the survival of men with locally advanced prostate cancer. Further reductions in the use of hormone therapy alone could further improve survival.

Impact of androgen deprivation therapy on apparent diffusion coefficient and T2w MRI for histogram and texture analysis with respect to focal radiotherapy of prostate cancer

“…Numerous independent studies found that prescribing androgen deprivation therapy (ADT) in addition to EBRT is associated with improved survival for patients with intermediate-risk and high-risk disease [ 13 ]. In today’s clinical practice, the combination of ADT and radiotherapy is considered as gold-standard treatment [ 14 , 15 ]. This has, however, a drawback with regard to imaging, since ADT leads to an increase in tumor apparent diffusion coefficient (ADC) and thus a decreased prostate cancer conspicuity [ 16 – 19 ].…”

Evaluating cancer research impact: lessons and examples from existing reviews on approaches to research impact assessment

“…This approach was taken because of the anticipated challenge of conducting a primary review of empirical examples of cancer research impact evaluation, and to allow a critique of empirical studies in the context of lessons learnt from the wider literature. A primary review would have been difficult because examples of cancer research impact evaluation, for example, the assessment of research impact on clinical guidelines [ 13 ], or clinical practice [ 14 – 16 ], are often not categorised in publication databases under the umbrella term of research impact. Reasons for this are the lack of medical subject heading (MeSH) search term relating to research impact assessment and the differing definitions for research impact.…”