Radiotherapy for treatment of early prostate cancer
Prostate Scotland Statement 30th September 2023
Radiotherapy for treatment of early prostate cancer
Following the announcement by the Royal Marsden Foundation Trust Hospital that a major international trial -the PACE B trial- looking at the comparative impacts of stereotactic body radiotherapy (SBRT) and external beam radiotherapy (EBRT) for treatment of low/intermediate risk early prostate cancer that SBRT can shorten time treatment time and reduce hospital attendances[i] Prostate Scotland stated:
‘It is very encouraging news that men with early prostate cancer can be effectively and safely given higher doses of radiotherapy as a treatment over a shorter time period, but with less overall radiotherapy. This gives the potential in the future for men with early prostate cancer who choose radiotherapy to be given the option of shorter radiotherapy treatment and reduced attendances at hospital. Shorter treatment times are also likely to also have benefits for the health service. Provision of this higher dose Stereotactic Body Radiation Therapy (SBRT) for early prostate cancer is already available in one centre in Scotland as part of a clinical trial’.
Notes to Editors:
For further information please contact Prostate Scotland at info@prostatescotland.org.uk or 0131 603 8660
External Beam Radiotherapy (EBRT) is currently used for radiotherapy treatment for early prostate cancer. It involves a special machine called a linear accelerator producing high energy x-raybeams which are then very carefully and accurately focused on the prostate. As all the organs inside the body lie quite close to each other, the beam is shaped by the use of multi-leaf collimators within the head of the linear accelerator. This beam is shaped to fit the anatomy and surrounding areas (prostate, bladder, back passage, hips) so the prostate can be accurately targeted and reduce the dose to the healthy surrounding normal tissues of the bladder and bowel. Although there may be variations in the treatment centre attained, usually there are in the region of between 20 to 40 treatments carried out over 4 to 8 weeks. It is becoming more common for men with low or intermediate risk to be given higher doses over a shorter period of time, often 20 fractions.
Stereotactic Body Radiation Therapy (SBRT) is an advanced form of radiotherapy treatment that is a type of external beam radiation treatment that delivers very precise and higher doses of radiation from outside the body. This works in the same way as other radiotherapy treatments to damage the cancer cells. Very sophisticated equipment is used to pinpoint the exact position of the tumour within the prostate and then delivers SBRT. To deliver SBRT, changes are made in the way that the LINAC machine is used; the dose rate is increased, and the beam is delivered without a flattening filter. In this way the direction of the radiation beams can be very precisely adjusted and corrected to the tumour site, supported by the use of a tumour tracking system. This allows for any movements or slight changes of position made by the patient. The dose of each fraction of radiotherapy is larger than with traditional EBRT. As a result, the treatment dose is delivered in 5 large doses of radiotherapy over 5 days.
The recent PACE trial data has showed that five year biochemical cure rates for men on the trial were high—96% of men on SBRT and 95% for those men on External Beam radiotherapy (EBRT) the current standard of care
Prostate Cancer In many cases where the prostate cancer has not spread, men will be offered surgery or radiotherapy treatments, with a curative intent. Prostate cancer is the most common cancer amongst men in Scotland, with a lifetime chance of one in ten men developing it[ii]. There were over 37,009 new registrations of men with prostate cancer between 2008 and 2018 and 9,782 deaths of men in Scotland from prostate cancer during that period [iii]. The most recent figures for Scotland prior to the pandemic show that 4066 men in Scotland were diagnosed with prostate cancer in 2019 and in 2021 4265 were diagnosed [iv]. 1066 men died from prostate cancer in 2021[iv]. Survival rates amongst men with prostate cancer have encouragingly doubled over the past two decades with 84% of men with prostate cancer now surviving it[v]. Projections by the NHS show that the diagnosis of men with prostate cancer is likely to rise by up to 35% over the decade to 2027[vi].
Prostate Scotland is a registered Scottish charity no SC037494. It was set up in 2006 as a Scottish charity to develop awareness of prostate disease, to support men and their families/ partners with the disease through providing advice and information and to advance treatment and research into prostate disease. Its aim is to reach out across Scotland to create greater awareness amongst men and their families/partners about prostate disease and to advance treatment. It has established an award winning website www.prostatescotland.org.uk providing a wide range of information about prostate disease and treatments, as well as providing information and advice about prostate disease to men and their families across Scotland. In 2010 the charity won a national award for its impact on community health and in 2013 and 2015 was commended in the British Medical Association Patient information Awards, and in 2017 was awarded Scottish health charity of the year.
Footnotes
[i] Alison C Tree et al The Lancet Sept 13, 2022 DOI: https://doi.org/10.1016/S1470-2045(22)00517-4
[ii] See Cancer Incidence in Scotland 2018 Public Health Scotland April 2020, Cancer mortality in Scotland 2018 Public Health Scotland October 2019
[iii] See Cancer in Scotland Public Health Scotland April 2020 and Scottish cancer registry Cancer mortality in Scotland 2018 Public Health Scotland October 2019 p8 and ISD Cancer in Scotland April 2019 Information Services Division, NHS National Services Scotland and PHS Scotland April 2020 and 20221 and Cancer Mortality in Scotland 2021 -PHS Scotland 2022
[iv] Cancer Incidence and Prevalence in Scotland to December 2021- Public Health Scotland 13 June 2023
[v] Cancer in Scotland: ISD, NHS National Services Scotland, October 2018 pp 16-2
[vi] See Scottish Cancer Registry May 2016 and Cancer Incidence in Scotland (2014), and Information Services Division NHS National Services Scotland November 2015
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