RESPONSE OF CANINE TUMORS TO NONSTANDARD FRACTIONATION

这项研究将在狗身上进行自然发生的鼻癌。 目的是评价肿瘤和急性期的放射反应。 正常组织对非常规分割方案反应迟缓。 已经有人提出加速辐射分馏 治疗剂量对控制快速增殖可能更有效。 肿瘤。也有人提出，后期正常情况下的一些减少 组织并发症可以在较小的每部分剂量下实现。如果 馏分之间的相互处理间隔和给出的总时间 总的辐射剂量可以减少，肿瘤就会减少 重新繁殖和再生的机会。如果剂量反应曲线 急性和迟发性反应正常组织的靶细胞显著 不同的、反应迟缓的正常组织可以通过较小的剂量幸免于难 每一部分，而反应强烈的组织不会经历 相应的伤害减少。肿瘤被认为是尖锐的 有反应的组织。提出的研究旨在验证这一理论。 并给出了剂量响应曲线的一般形状的估计 肿瘤和急性和迟发性反应组织。可变总剂量将为 给患有鼻癌的三组狗服用。每一组都将 接收不同大小的每一部分的剂量以获得可变的总剂量 剂量。所有照射剂量将每隔四周给予一次。 将进行分析，以确定肿瘤控制的50%可能性 一年；敏锐反应水平的概率 组织，特别是眼睛的结构；以及迟发的可能性 坏死。这些数据将允许评估剂量大小的影响 肿瘤控制所需总剂量的每分数、早期效果和 晚期并发症。等效应曲线将被构建为不同的 组织使用从三种不同剂量的每一种获得的数据 分数组。

This study will be done with naturally occurring nasal carcinomas in dogs. The purpose is to evaluate the radiation response of tumor and acute and late responding normal tissues to nonconventional fractionation schemes. It has been proposed that accelerated fractionation of the radiation therapy dose might be more effective for control of rapidly proliferating tumors. It has also been proposed that some reduction in late normal tissue complications could be achieved with smaller doses per fraction. If the intertreatment interval between fractions and the overall time to give a total dose of radiation can be reduced, tumors would have less opportunity for repopulation and regrowth. If the dose response curves of target cells for acute and late responding normal tissues are significantly different, late responding normal tissues may be spared by smaller doses per fraction while acutely responding tissues will not experience a corresponding decrease in injury. Tumors are considered to be acutely responding tissues. The research proposed is designed to test the theory and to give estimates of the general shapes of dose response curves for tumor and acute and late responding tissues. Variable total doses will be given to three groups of dogs with nasal carcinomas. Each group will receive a different size of dose per fraction to achieve the variable total doses. All irradiation doses will be given in an interval of four weeks. Analysis will be done to determine the 50% probability for tumor control at one year; the probability for levels of response of acutely responding tissues, particularly the structures of the eye; and probability for late necrosis. The data will permit evaluation of the effect of size of dose per fraction on total dose required for tumor control, early effects and late complications. Isoeffect curves will be constructed for the various tissues using data obtained from each of the three different dose per fraction groups.