Bley Carla Rohrer, Sumova Andrea, Roos Malgorzata, Kaser-Hotz Barbara
University of Zürich, Section of Diagnostic Imaging and Radiation Oncology of the Vetsuisse-Faculty, Winterthurerstrasse 260, CH-8057 Zürich, Switzerland.
J Vet Intern Med. 2005 Nov-Dec;19(6):849-54. doi: 10.1892/0891-6640(2005)19[849:iobtid]2.0.co;2.
Radiation therapy is the treatment of choice for many primary canine brain tumors. The radiation dose tolerated by surrounding healthy brain tissue can be a limiting factor for radiation treatment and total dose as well as fractionation schedules, and volume effects may play a role in the outcome of patients undergoing radiation therapy. The purpose of this retrospective study was to evaluate the efficacy of radiation therapy in dogs with brain tumors that showed signs of neurologic disease. Forty-six dogs with brain tumors were included in the analysis. In 34 dogs, computer-generated treatment plans were available, and dose-volume data could be obtained. The totally prescribed radiation therapy doses ranged from 35 to 52.5 Gy (mean = 40.9 [SD +/- 2.91) applied in 2.5- to 4-Gy fractions (mean = 3.2). The median overall survival time calculated for deaths attributable to worsening of neurologic signs was 1,174 days (95% confidence interval [CI], 693-1,655 days). Assuming that all deaths were due to disease or treatment consequences, the median survival time was 699 days (95% CI, 589-809 days). No prognostic clinical factors such as the location or size of the tumor or neurologic signs at presentation were identified. With computerized treatment planning and accurate positioning, high doses of radiation (> 80% of the total dose) could be limited to mean relative brain volumes of 35.3% (+/- 12.6). These small volumes may decrease the probability of severe late effects such as infarction or necrosis. In this study, very few immediate or early delayed adverse effects and no late effects were noted, and quality of life was good to excellent.
放射治疗是许多原发性犬脑肿瘤的首选治疗方法。周围健康脑组织所能耐受的放射剂量可能是放射治疗、总剂量以及分割方案的限制因素，而容积效应可能会影响接受放射治疗患者的预后。这项回顾性研究的目的是评估放射治疗对出现神经疾病症状的犬脑肿瘤的疗效。46只患有脑肿瘤的犬被纳入分析。其中34只犬有计算机生成的治疗计划，且可获取剂量-容积数据。规定的放射治疗总剂量范围为35至52.5 Gy（平均 = 40.9 [标准差±2.91]），以2.5至4 Gy的分割剂量给予（平均 = 3.2）。因神经症状恶化导致死亡的中位总生存时间为1174天（95%置信区间[CI]，693 - 1655天）。假设所有死亡均由疾病或治疗后果导致，中位生存时间为699天（95%CI，589 - 809天）。未发现预后临床因素，如肿瘤位置、大小或就诊时的神经症状。通过计算机化治疗计划和精确的定位，高剂量放射（>总剂量的80%）可局限于平均相对脑容积为35.3%（±12.6）的范围。这些小容积可能会降低严重晚期效应如梗死或坏死的发生概率。在本研究中，未观察到极少的即刻或早期延迟不良反应，也未出现晚期效应，生活质量良好至优秀。
