论文标题
迈向乳腺癌治疗的个性化计算机模拟
Towards personalized computer simulations of breast cancer treatment
论文作者
论文摘要
癌症病理是给定个人独有的,开发个性化的诊断和治疗方案是主要问题。数学建模和模拟是一种个性化癌症医学的有前途的方法。然而,癌症的复杂性,异质性和多阶段性质带来了严重的挑战。使用数学模型预测特定患者治疗方案结果的主要障碍之一在于其初始化和参数化,以便准确反映个体的癌症特征。在这里,我们介绍了一项研究,在其中使用多元测量值在单个乳腺肿瘤上常规获取,包括组织病理学,磁共振成像(MRI)和分子分析,以个性化用化学疗法和抗雄激素治疗的乳腺癌的多例混合细胞自动机模型。我们在肿瘤组织水平上对药物的药代动力学和药效学对象进行了建模,但具有细胞和亚细胞分辨率。我们在12周的治疗方案的肿瘤部分的2D横截面中模拟了这些时空动力学,从而产生了复杂且计算密集的模拟。对于这种计算要求的系统,在实践中,直到最近在机器学习技术出现用于无可能的推理方法之后,实际上才可行地估算数据的形式统计推理方法。在这里,我们使用贝叶斯优化提供的推论进步,以适合我们的模型模拟单个患者的数据。这样,我们研究是否可以从肿瘤组织中细胞密度的一系列测量值中估算一些关键参数,以及需要进行测量以进行可靠的预测。
Cancer pathology is unique to a given individual, and developing personalized diagnostic and treatment protocols are a primary concern. Mathematical modeling and simulation is a promising approach to personalized cancer medicine. Yet, the complexity, heterogeneity and multiscale nature of cancer present severe challenges. One of the major barriers to use mathematical models to predict the outcome of therapeutic regimens in a particular patient lies in their initialization and parameterization in order to reflect individual cancer characteristics accurately. Here we present a study where we used multitype measurements acquired routinely on a single breast tumor, including histopathology, magnetic resonance imaging (MRI), and molecular profiling, to personalize a multiscale hybrid cellular automaton model of breast cancer treated with chemotherapeutic and antiangiogenic agents. We model drug pharmacokinetics and pharmacodynamics at the tumor tissue level but with cellular and subcellular resolution. We simulate those spatio-temporal dynamics in 2D cross-sections of tumor portions over 12-week therapy regimes, resulting in complex and computationally intensive simulations. For such computationally demanding systems, formal statistical inference methods to estimate individual parameters from data have not been feasible in practice to until most recently, after the emergence of machine learning techniques applied to likelihood-free inference methods. Here we use the inference advances provided by Bayesian optimization to fit our model to simulated data of individual patients. In this way, we investigate if some key parameters can be estimated from a series of measurements of cell density in the tumor tissue, as well as how often the measurements need to be taken to allow reliable predictions.