Herrmann T, Christen N, Alheit H D
Abteilung Strahlentherapie, Medizinische Akademie Carl Gustav Carus, Dresden.
Strahlenther Onkol. 1993 Mar;169(3):141-51.
The transition from low-dose-rate (LDR) brachytherapy to high-dose-rate (HDR) afterloading treatment is in progress in most centres of radiation therapy. First reports of studies comparing HDR and LDR treatment in cervix cancer demonstrate nearly equal local control. In our own investigations on 319 patients with primary irradiated carcinoma of the cervix (125 HDR/194 LDR) we found the following control rates: Stage FIGO I 95.4%/82.9% (HDR versus LDR), stage FIGO II 71.4%/73.7%, stage FIGO III 57.9%/38.5%. The results are not significant. The side effects--scored after EORT/RTOG criteria--showed no significant differences between both therapies for serious radiogenic late effects on intestine, bladder and vagina. The study and findings from the literature confirm the advantage of the HDR-procedure for patient and radiooncologist and for radiation protection showing at least the same results as in the LDR-area. As for radiobiological point of view it is important to consider that the use of fractionation in the HDR-treatment is essential for the sparing of normal tissues and therefore a greater number of small fractionation doses in the brachytherapy should be desirable too. On the other hand the rules, which are true for fractionated percutaneous irradiation therapy (overall treatment time as short as possible to avoid repopulation of tumor cells) should be taken into consideration in combined brachy-teletherapy regime in gynecologic tumors. The first step in this direction may be accelerated regime with a daily application of both treatment procedures. The central blocking of the brachytherapy region from the whole percutaneous treatment target volume should be critically reflected, especially in the case of advanced tumors.
在大多数放射治疗中心，低剂量率（LDR）近距离放射治疗向高剂量率（HDR）后装治疗的转变正在进行中。关于宫颈癌中比较HDR和LDR治疗的研究的首批报告显示局部控制效果几乎相同。在我们自己对319例原发性宫颈照射癌患者（125例HDR/194例LDR）的研究中，我们发现了以下控制率：国际妇产科联盟（FIGO）I期为95.4%/82.9%（HDR对比LDR），FIGO II期为71.4%/73.7%，FIGO III期为57.9%/38.5%。结果无显著差异。根据欧洲肿瘤放射治疗协作组（EORT）/美国放射肿瘤学会（RTOG）标准评分的副作用显示，两种治疗方法在对肠道、膀胱和阴道的严重放射性晚期效应方面无显著差异。该研究以及文献中的发现证实了HDR程序对患者、放射肿瘤学家和辐射防护的优势，其结果至少与LDR领域相同。从放射生物学角度来看，重要的是要考虑到在HDR治疗中使用分次照射对于保护正常组织至关重要，因此在近距离放射治疗中也应采用更多的小分次剂量。另一方面，在妇科肿瘤的近距离 - 远距离联合治疗方案中，应考虑适用于分次经皮照射治疗的规则（总治疗时间尽可能短以避免肿瘤细胞再增殖）。朝着这个方向的第一步可能是每天同时应用两种治疗程序的加速方案。应严格反思近距离放射治疗区域与整个经皮治疗靶体积的中心遮挡问题，尤其是在晚期肿瘤的情况下。
