Strigari L, Benassi M, Chiesa C, Cremonesi M, Bodei L, D'Andrea M
Laboratory of Medical Physics and Expert Systems, Regina Elena National Cancer Institute, Rome, Italy.
Q J Nucl Med Mol Imaging. 2011 Apr;55(2):205-21.
The linear quadratic model (LQM) has largely been used to assess the radiobiological damage to tissue by external beam fractionated radiotherapy and more recently has been extended to encompass a general continuous time varying dose rate protocol such as targeted radionuclide therapy (TRT). In this review, we provide the basic aspects of radiobiology, from a theoretical point of view, starting from the "four Rs" of radiobiology and introducing the biologically effective doses, which may be used to quantify the impact of a treatment on both tumors and normal tissues. We also present the main parameters required in the LQM, and illustrate the main models of tumor control probability and normal tissue complication probability and summarize the main dose-effect responses, reported in literature, which demonstrate the tentative link between targeted radiotherapy doses and those used in conventional radiotherapy. A better understanding of the radiobiology and mechanisms of action of TRT could contribute to describe the clinical data and guide the development of future compounds and the designing of prospective clinical trials.
线性二次模型（LQM）在很大程度上已被用于评估外照射分割放疗对组织的放射生物学损伤，最近该模型已扩展到涵盖一般的连续时间变化剂量率方案，如靶向放射性核素治疗（TRT）。在本综述中，我们从理论角度提供放射生物学的基本方面，从放射生物学的“四个R”开始，并介绍生物学有效剂量，其可用于量化治疗对肿瘤和正常组织的影响。我们还介绍了LQM所需的主要参数，阐述了肿瘤控制概率和正常组织并发症概率的主要模型，并总结了文献中报道的主要剂量效应反应，这些反应表明了靶向放疗剂量与传统放疗中使用的剂量之间的初步联系。更好地理解TRT的放射生物学和作用机制有助于描述临床数据，并指导未来化合物的开发和前瞻性临床试验的设计。
