Aims

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.

Materials and methods

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.

Results

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.

Conclusions

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.

中文翻译：

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英国放射治疗利用马尔萨斯模型的更新

宗旨

Malthus 计划通过将癌症发病率数据与详细说明放疗适应症和适当剂量分割的决策树相结合来预测国家和地方放疗需求。自 2017 年上一次模型更新以来，技术进步和 COVID-19 大流行导致放射治疗计划的大分割增加。放射治疗的适应症也有所发展，特别是在寡转移性疾病的情况下。在这里，我们对 2021 年的模型进行了简要更新。我们更新了乳腺癌、前列腺癌、肺癌和头颈癌的决策树，并将最近的癌症发病率数据纳入我们的模型，生成了这四种癌症的当前需求估计值英格兰各地的癌症研究中心。

材料和方法

决策树更新基于改变实践的随机对照试验、已发布指南、审计数据和专家意见的证据。特定地点和特定阶段的发病率数据取自国家疾病登记服务中心。我们使用更新后的模型来估计 2021 年在国家和临床委托组层面接受放射治疗的患者比例（适当的放射治疗率）和每百万人口的需求分数。

结果

与 2017 年版本相比，我们新模型中所有四个癌症部位的总预测分数需求下降了 11.4%。这种减少主要是由于更多地使用大分割治疗（包括立体定向消融放疗）和向早期表现的转变。适当放疗率的唯一大变化是肺癌绝对下降 3%。

结论

与我们之前的模型相比，当前版本预测整个英格兰的分数需求会减少。这主要是由放射治疗方案的大分割驱动的，使用的技术需要越来越复杂的规划。在将分数负担转化为直线加速器需求或吞吐量时，需要考虑处理复杂性和本地服务因素。