Department of Radiation Oncology, Marilia Medicine School, São Paulo, Brazil.
Int J Radiat Oncol Biol Phys. 2012 Feb 1;82(2):e181-5. doi: 10.1016/j.ijrobp.2010.11.017. Epub 2011 May 17.
Postoperative adjuvant treatment using β-radiotherapy (RT) is a proven technique for reducing the recurrence of pterygium. A randomized trial was conducted to determine whether a low fractionation dose of 2 Gy within 10 fractions would provide local control similar to that after a high fractionation dose of 5 Gy within 7 fractions for surgically resected pterygium.
A randomized trial was conducted in 200 patients (216 pterygia) between February 2006 and July 2007. Only patients with fresh pterygium resected using a bare sclera method and given RT within 3 days were included. Postoperative RT was delivered using a strontium-90 eye applicator. The pterygia were randomly treated using either 5 Gy within 7 fractions (Group 1) or 2 Gy within 10 fractions (Group 2). The local control rate was calculated from the date of surgery.
Of the 216 pterygia included, 112 were allocated to Group 1 and 104 to Group 2. The 3-year local control rate for Groups 1 and 2 was 93.8% and 92.3%, respectively (p = .616). A statistically significant difference for cosmetic effect (p = .034), photophobia (p = .02), irritation (p = .001), and scleromalacia (p = .017) was noted in favor of Group 2.
No better local control rate for postoperative pterygium was obtained using high-dose fractionation vs. low-dose fractionation. However, a low-dose fractionation schedule produced better cosmetic effects and resulted in fewer symptoms than high-dose fractionation. Moreover, pterygia can be safely treated in terms of local recurrence using RT schedules with a biologic effective dose of 24-52.5 Gy(10.).
β 射线放疗（RT）术后辅助治疗已被证实可降低翼状胬肉的复发率。本研究采用随机对照试验，旨在确定对于接受巩膜切除术的翼状胬肉患者，2 Gy 低分割剂量（10 次分割）是否与 5 Gy 高分割剂量（7 次分割）具有相似的局部控制效果。
2006 年 2 月至 2007 年 7 月期间，我们对 200 例（216 只眼）患者进行了一项随机对照试验。纳入标准为：单纯行巩膜切除术切除的新鲜翼状胬肉，术后 3 天内行 RT 治疗。术后 RT 采用锶-90 眼敷贴器进行治疗。随机采用 5 Gy （7 次分割，第 1 组）或 2 Gy （10 次分割，第 2 组）进行分割放疗。局部控制率从手术日期开始计算。
216 只眼中，112 只眼纳入第 1 组，104 只眼纳入第 2 组。第 1 组和第 2 组的 3 年局部控制率分别为 93.8%和 92.3%（p =.616）。第 2 组在美容效果（p =.034）、畏光（p =.02）、刺激感（p =.001）和巩膜软化（p =.017）方面的结果明显优于第 1 组。
高分割剂量与低分割剂量在术后翼状胬肉的局部控制率方面并无显著差异。然而，低分割剂量方案的美容效果更好，且症状更少。此外，对于 RT 治疗，采用生物有效剂量为 24-52.5 Gy（10）的分割方案治疗翼状胬肉，在局部复发方面是安全的。
