THE BIOLOGICAL BASIS FOR CONFORMAL 3-DIMENSIONAL RADIATION-THERAPY
THE BIOLOGICAL BASIS FOR CONFORMAL 3-DIMENSIONAL RADIATION-THERAPY
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DOI：
10.1016/0360-3016(91)90701-5
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发表时间：
1991-08-01
影响因子：
7
通讯作者：
FUKS, Z
中科院分区：
文献类型：
--
作者：
LEIBEL, SA;LING, CC;FUKS, Z
最近引入的用于治疗计划的新计算机技术和计算机驱动的治疗实施系统（例如多叶准直器和在线验证系统）加速了 3 维 (3-D) 放射治疗作为癌症治疗方式的发展。 3D治疗计划的目标是使高辐射剂量的空间分布符合肿瘤轮廓的形状，同时减少接受高辐射剂量的周围正常组织的体积。肿瘤覆盖精度的提高和正常组织的排除应允许肿瘤剂量递增，并可能增强局部肿瘤控制。有人建议，局部控制改善所带来的任何生存增益可能会被初始诊断时已存在的微转移所引起的远处转移所抵消。然而，临床和实验室研究表明，在初始治疗时未能控制原发肿瘤会显着增加转移播散的发生率。这种现象与以下假设一致：与局部复发性原发性肿瘤的再生长过程相关的有丝分裂活性增强促进非转移性肿瘤细胞多步转化为具有转移潜力的克隆原，从而导致转移性疾病的总体发生率增加。这些生物学考虑因素支持需要将注意力集中在确定更有效的治疗策略上，这些策略旨在在初始治疗时完全根除原发性局部肿瘤，并作为使用 3-D 适形放射治疗的临床研究的基本原理。
The recent introduction of new computer technology for treatment planning and computer-driven treatment delivery systems, such as multi-leaf collimators and on-line verification systems, has accelerated the development of 3-dimensional (3-D) radiation therapy as a modality for curative cancer treatment. The goal of 3-D treatment planning is to conform the spatial distribution of the high radiation dose to the shape of the tumor contour while concomitantly decreasing the volume of the surrounding normal tissues receiving high radiation doses. The improved precision of tumor coverage and the exclusion of normal tissues should permit tumor dose escalation and may enhance local tumor control. It has been suggested that any survival gains derived from improvements in local control may be offset by the subsequent appearance of distant metastases arising from micrometastases already present at the time of initial diagnosis. However, clinical and laboratory studies indicate that failure to control the primary tumor at the time of initial treatment significantly increases the incidence of metastatic dissemination. This phenomenon is consistent with the hypothesis that the enhanced mitotic activity associated with the re-growth process of locally recurring primary tumors promotes the multi-step transformation of non-metastatic tumor cells into clonogens with metastatic potential, leading to increased overall rates of metastatic disease. These biologic considerations provide support for the need to focus attention on the identification of more effective therapeutic strategies designed to eradicate the primary local tumor completely at the time of initial therapy and serve as the rationale for clinical studies using 3-D conformal radiation therapy.