摘要
目的:本文回顾性研究一组连续收治行放射治疗的恶性胸腺肿瘤病例,应用剂量体积直方图分析心脏受照情况,同时结合临床随访放射性心脏损伤的结果,探讨了影响心脏损伤的因素和避免或减少心脏损伤的有效方法。方法:1983年3月至2001年9月,50例胸腺肿瘤患者在北京大学临床肿瘤学院放射治疗科接受放射治疗。Masaoka分期Ⅱ期14例,Ⅲ期22例和Ⅳ期14例。47例患者接受普通二维技术放射治疗,三例患者接受三维适形放射治疗。治疗的剂量范围为10Gy～84.5Gy穴中位剂量为55Gy雪。根治性放疗20例,术后放疗14例,术前放疗2例和姑息性放疗14例。对所有病例均在三维治疗计划系统上模拟进行CT图象的三维重建和剂量分布的计算,由心脏的剂量体积直方图,借助于正常组织和器官并发症概率模型,计算心脏1/3等效体积的等效剂量,进而导出放射相关心脏疾患发生的概率,并与临床观测结果进行比较。结果:普通照射技术治疗组的心脏等效1/3体积中位剂量为57.9Gy穴21.6Gy～83.3Gy雪;三维适形放射治疗的心脏等效1/3体积中位剂量为26.3Gy穴22.7Gy～52.0Gy雪。全组病例中位随访期为13个月(0.6～111.3个月)。在45例有心脏状况记录的病例中发现7例有放射相关的心脏疾患,SOMA分级1～3级。结论:该研究结果表明,心脏损伤随着心脏等效体积剂量增大而明?
Objective: To determine the effects of radiation of mediastinal tumors on radiation-induced heart disease and refine the radiotherapy approach for clinical treatment to reduce cardiac toxicity- a series of consecutive cases treated by radiotherapy for malignant thymic tumor was retrospectively studied. Methods: Between Mar 1983 and Sep 2001- 50 consecutive patients were treated by radiotherapy for malignant thymic tumors (14 at Masaoka stage Ⅱ- 22 at stage Ⅲ- and 14 at stage Ⅳ ) in the department of radiotherapy- the school of oncology- Peking university. The conventional radiotherapy method (traditional 2D radiotherapy) was performed in forty-seven of these patients and 3D conformal radiotherapy has been used in 3 patients since Oct 2001 and the total dose for the patients ranged from 10 Gy to 84.5 Gy (median of 55 Gy). Radiotherapy consisted of radical (in 20)- postoperative (in 14)- preoperative (in 2) and palliative (in 14). The DVH of heart in radiotherapy for all patients and dose on the 3D therapy planning system was analyzed using 3D reconstruction of CT image. By DVH and healthy-tissue complication probabilities model- isoeffective dose for 1/3 isoeffective volume and radiation-induced heart disease probabilities were calculated and compared with clinical results. Result: The median follow-up for the patients was 13 months (0.6-111.3). Median dose of the one-third heart effective volume was 57.9 Gy (ranged from 21.6 to 83.3 Gy) for conventional radiotherapy and 26.3 Gy (ranged from 22.7 Gy to 52.0 Gy) for 3D conformal radiotherapy. Radiation-induced heart disease was observed in seven of 45 patients with records of cardiac situation during the period of follow-up. Cardiac toxicity of these seven were evaluated as SOMA stage 1-3. Conclusion: A significant association between cardiac toxicity and heart effective volume dose was found in this study (P<0.001). However- there are not significant (P=0.058) between cardiac toxicity and therapeutic dose for malignant thymic tumor. It is able to reduce the dose received by heart by 3D conformal radiotherapy effectively. Healthy-tissue complication probabilities binomial model can successfully interpret radiation-induced heart complication probabilities after radiotherapy for malignantthymic tumors radiotherapy and should be served as an important factor for optimization of radiotherapy planning on patients with mediastinal tumors.
出处
《中国医学物理学杂志》
CSCD
2003年第4期197-199,231,共4页
Chinese Journal of Medical Physics
