Isaeva2009 - Different strategies for cancer treatment

We formulate and analyse a mathematical model describing immune response to avasculartumour under the influence of immunotherapy and chemotherapy and their combinations aswell as vaccine treatments. The effect of vaccine therapy is considered as a parametricperturbation of the model. In the case of a weak immune response, neither immunotherapy norchemotherapy is found to cause tumour regression to a small size, which would be below theclinically detectable threshold. Numerical simulations show that the efficiency of vaccinetherapy depends on both the tumour size and the condition of immune system as well as on theresponse of the organism to vaccination. In particular, we found that vaccine therapy becomesmore effective when used without time delay from a prescribed date of vaccination after surgeryand is ineffective without preliminary treatment. For a strong immune response, our modelpredicts the tumour remission under vaccine therapy. Our study of successive chemo/immuno,immuno/chemo and concurrent chemoimmunotherapy shows that the chemo/immunosequence is more effective while concurrent chemoimmunotherapy is more sparing.

本研究构建并分析了一款数学模型，用以描述免疫治疗、化疗及其联合方案与疫苗治疗作用下，机体对无血管肿瘤（avascular tumour）的免疫应答过程。本研究将疫苗治疗的效应视作该模型的参数扰动项。当机体免疫应答较弱时，免疫治疗与化疗均无法使肿瘤退缩至临床可检测阈值以下的微小体积。数值模拟结果显示，疫苗治疗的疗效不仅取决于肿瘤体积与免疫系统状态，还与机体对疫苗接种的应答情况相关。具体而言，本研究发现，若在术后规定的疫苗接种日期无延迟地启动疫苗治疗，其疗效更佳；未进行预处理的疫苗治疗则无法发挥预期效果。当机体免疫应答较强时，本模型预测疫苗治疗可实现肿瘤缓解。本研究针对序贯化疗-免疫治疗、序贯免疫-化疗治疗以及同步化学免疫联合治疗（chemoimmunotherapy）的分析表明，化疗-免疫序贯方案的疗效更优，而同步化学免疫联合治疗对机体更为温和。