School of Clinical Medicine, University of Cambridge, Cambridge, UK.
Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK; The Christie NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK.
Clin Oncol (R Coll Radiol). 2023 Jan;35(1):e1-e9. doi: 10.1016/j.clon.2022.06.006. Epub 2022 Jul 11.
The Malthus Programme predicts national and local radiotherapy demand by combining cancer incidence data with decision trees detailing the indications, and appropriate dose fractionation, for radiotherapy. Since the last model update in 2017, technological advancements and the COVID-19 pandemic have led to increasing hypofractionation of radiotherapy schedules. Indications for radiotherapy have also evolved, particularly in the context of oligometastatic disease. Here we present a brief update on the model for 2021. We have updated the decision trees for breast, prostate, lung and head and neck cancers, and incorporated recent cancer incidence data into our model, generating a current estimate of fraction demand for these four cancer sites across England.
The decision tree update was based on evidence from practice-changing randomised controlled trials, published guidelines, audit data and expert opinion. Site- and stage-specific incidence data were taken from the National Disease Registration Service. We used the updated model to estimate the proportion of patients who would receive radiotherapy (appropriate rate of radiotherapy) and the fraction demand per million population at a national and Clinical Commissioning Group level in 2021.
The total predicted fraction demand has decreased by 11.4% across all four cancer sites in our new model, compared with the 2017 version. This reduction can be explained primarily by greater use of hypofractionated treatments (including stereotactic ablative radiotherapy) and a shift towards earlier stage presentation. The only large change in appropriate rate of radiotherapy was an absolute decrease of 3% for lung cancer.
Compared with our previous model, the current version predicts a reduction in fraction demand across England. This is driven principally by hypofractionation of radiotherapy regimens, using technology that requires increasingly complex planning. Treatment complexity and local service factors need to be taken into account when translating fraction burden into linear accelerator demand or throughput.
马尔萨斯计划通过结合癌症发病率数据和详细说明放疗适应症和适当剂量分割的决策树来预测国家和局部放疗需求。自 2017 年最后一次模型更新以来，技术进步和 COVID-19 大流行导致放疗计划的分割越来越少。放疗适应症也发生了变化，特别是在寡转移疾病的背景下。在这里，我们简要介绍一下 2021 年的模型更新。我们更新了乳腺癌、前列腺癌、肺癌和头颈部癌症的决策树，并将最近的癌症发病率数据纳入我们的模型，生成了这四个癌症部位在英格兰的当前分割需求估计。
决策树更新基于改变实践的随机对照试验、已发表的指南、审计数据和专家意见的证据。特定部位和阶段的发病率数据来自国家疾病登记处。我们使用更新后的模型来估计 2021 年全国和临床委托组层面上接受放疗的患者比例（适当放疗率）和每百万人口的分割需求。
与 2017 年的版本相比，我们新模型中所有四个癌症部位的总预测分割需求减少了 11.4%。这种减少主要可以解释为更广泛地使用分割放疗（包括立体定向消融放疗）和更早的分期表现。唯一放疗适当率的大幅变化是肺癌绝对减少了 3%。
与我们之前的模型相比，当前版本预测英格兰的分割需求减少。这主要是由放疗方案的分割减少驱动的，使用了需要越来越复杂规划的技术。在将分割负担转化为直线加速器需求或吞吐量时，需要考虑治疗的复杂性和当地服务因素。
