Dubben H H, Beck-Bornholdt H P
Institute of Biophysics and Radiobiology, University of Hamburg, Germany.
Acta Oncol. 1993;32(1):79-82. doi: 10.3109/02841869309083890.
Rhabdomyosarcomas R1H of the rat (WAG/Rij) were treated using fractionation schedules including a boost. The total dose was 60 Gy. Overall treatment time was 6 weeks. Four different boost schedules were applied: a single dose boost (12.15 Gy) at the last day of treatment, a single dose boost (12.15 Gy) at the first day of treatment, a schedule including the boost in 7 fractions during the first week, and a schedule including the boost in 10 fractions during the first week of treatment. A standard schedule with 30 fractions of 2 Gy without a boost was used for comparison. Initially accelerated schedules, i.e. those with a boost at start of treatment, revealed higher effect on tumour parenchyma as monitored by local control rate and net growth delay. This could be due to a decrease of radio-sensitivity, that is, an increase of the hypoxic fraction of clonogenic tumour cells during fractionated irradiation.
采用包括加量照射在内的分割方案治疗大鼠(WAG/Rij)的R1H横纹肌肉瘤。总剂量为60 Gy。总治疗时间为6周。应用了四种不同的加量方案:在治疗最后一天单次加量(12.15 Gy)、在治疗第一天单次加量(12.15 Gy)、在第一周分7次加量的方案以及在治疗第一周分10次加量的方案。使用30次2 Gy无加量的标准方案作为对照。最初的加速方案,即在治疗开始时加量的方案,通过局部控制率和净生长延迟监测显示对肿瘤实质有更高的疗效。这可能是由于放射敏感性降低,即分次照射期间克隆性肿瘤细胞缺氧部分增加所致。