Veen Ronald E, Kal Henk B
Department of Radiotherapy, University Medical Center, Utrecht, The Netherlands.
Int J Radiat Oncol Biol Phys. 2007 Nov 15;69(4):1205-8. doi: 10.1016/j.ijrobp.2007.04.032.
The aim of this study is to show the efficiency of keloidectomy and postoperative interstitial high-dose-rate (HDR) brachytherapy in the prevention of keloids.
Between 1998 and 2004, 35 patients with 54 keloids were treated postoperatively with HDR brachytherapy. The first HDR dose was applied within 6 hours after surgery, and two additional HDR doses were administered on the next day with a six-hour interval. The majority of patients received 6 Gy as the first dose postsurgery and two fractions of 4 Gy (38 keloids) on the next day. Seven keloids were treated postoperatively with three fractions of 6 Gy. The biologically effective dose (BED), derived from the linear quadratic concept, was applied to calculate the BED for the various radiation regimens. The keloid recurrence rates at specific BED values were compared with those derived for other fractionation schemes in the literature.
Four recurrences/nonsatisfactory results out of nine treated keloids were observed after treatments with 1 x 4 Gy + 2 x 3 Gy. Only one recurrence out of 38 was found after 1 x 6 Gy + 2 x 4 Gy and none after 3 x 6 Gy. Better cosmetic results were found at the higher-dose schemes.
The results of this study prove the effectiveness of HDR brachytherapy after keloidectomy provided that the total HDR dose is sufficient. Currently our scheme is 3 x 6 Gy.
本研究的目的是展示瘢痕疙瘩切除术及术后组织间高剂量率(HDR)近距离放射治疗在预防瘢痕疙瘩方面的有效性。
1998年至2004年间,35例患有54个瘢痕疙瘩的患者术后接受了HDR近距离放射治疗。首次HDR剂量在术后6小时内给予,次日再给予另外两个HDR剂量,间隔6小时。大多数患者术后首次剂量接受6 Gy,次日接受两个4 Gy分割剂量(38个瘢痕疙瘩)。7个瘢痕疙瘩术后接受三个6 Gy分割剂量治疗。根据线性二次模型得出生物等效剂量(BED),用于计算不同放疗方案的BED。将特定BED值下的瘢痕疙瘩复发率与文献中其他分割方案得出的复发率进行比较。
采用1×4 Gy + 2×3 Gy治疗后,9个接受治疗的瘢痕疙瘩中有4个复发/效果不满意。采用1×6 Gy + 2×4 Gy治疗后,38个瘢痕疙瘩中仅1个复发,采用3×6 Gy治疗后无复发。高剂量方案的美容效果更佳。
本研究结果证明,瘢痕疙瘩切除术后HDR近距离放射治疗是有效的,前提是HDR总剂量足够。目前我们的方案是3×6 Gy。