Sakamoto Takashi, Oya Natsuo, Shibuya Keiko, Nagata Yasushi, Hiraoka Masahiro
Department of Radiation Oncology, Kumamoto University, Japan.
Radiother Oncol. 2009 May;91(2):271-6. doi: 10.1016/j.radonc.2008.12.018. Epub 2009 Feb 7.
The treatment dose and fractionation dose that are considered in postoperative keloids had been reported in the previous studies. We performed retrospective analysis to elucidate the factors influencing the treatment outcome.
From 1979 to 1994, 194 lesions in 119 patients received postoperative radiotherapy after excision with the total dose ranging from 16 Gy/8 fr to 40 Gy/8 fr (mean: biologically effective dose (BED) 33.5 Gy). Kilo-voltage X-rays (55 or 100 kVp) or electron beams (4 or 6 MeV), including entire keloid scars, and any suture/puncture holes with a margin around the lesion were used. The median follow-up period was 36 months (range 12-164 months).
Symptomatic pain and itching relief were achieved in 96% and 91%, respectively. The relapse rate was 11% at 20 Gy in five fractions or higher dose, while 43% at less than 20 Gy. On the other hand, the incidence of adverse effects was significantly higher for patients receiving more than 20 Gy in five fractions.
There was a significant correlation between the relapse rate and the total dose of irradiation, and between adverse effects and the total dose. To correlate local control and adverse effects, we proposed 20 Gy in five fractions as the optimal dose for the postoperative of keloids. A significant correlation between relapse rate and the interval time between excision and radiotherapy was not found in our current study.
以往研究已报道了术后瘢痕疙瘩的治疗剂量和分割剂量。我们进行了回顾性分析以阐明影响治疗结果的因素。
1979年至1994年，119例患者的194个病灶在切除术后接受了放射治疗，总剂量范围为16 Gy/8次分割至40 Gy/8次分割（平均：生物等效剂量（BED）33.5 Gy）。采用千伏X射线（55或100 kVp）或电子束（4或6 MeV），照射范围包括整个瘢痕疙瘩瘢痕以及病灶周围带有边缘的任何缝线/穿刺孔。中位随访期为36个月（范围12 - 164个月）。
分别有96%和91%的患者症状性疼痛和瘙痒得到缓解。五分割20 Gy或更高剂量时复发率为11%，而低于20 Gy时为43%。另一方面，五分割接受超过20 Gy的患者不良反应发生率显著更高。
复发率与总照射剂量之间、不良反应与总剂量之间存在显著相关性。为了平衡局部控制和不良反应，我们提出五分割20 Gy作为瘢痕疙瘩术后的最佳剂量。在我们目前的研究中未发现复发率与切除和放疗之间的间隔时间存在显著相关性。
