中文摘要：

目的比较乳腺癌保乳手术后瘤床电子线二维补量和X射线三维调强补量方法对肿瘤局部控制率及患者生存的影响。方法回顾性分析485例于北京肿瘤医院接受乳腺癌保乳手术的患者，术后全乳腺照射46～50Gy／23～25次后，一组患者采用电子线技术，另一组采用X射线调强技术进行瘤床补量放疗，补量剂量均为10～16Gy／5～8次。结果全组患者的中位随访时间为96．04个月。X射线调强瘤床补量组的5年和10年无局部复发生存率（LRFS）均为98．4％，明显优于电子线补量组5年的94．2％和10年的93．2％（x^2=4．190，P〈0．05）。但两组的总生存率（OS）间无明显差异，X射线组5年和10年的OS率分别为96．7％和95．8％，电子线组的分别为94．9％和89．4％（P〉0．05）。在多因素分析中，年龄≤40岁、腋窝淋巴结有转移及Her-2高表达是LRFS的独立预后因素，而放疗瘤床补量方式不是LRFS和OS的预后因素（P〉0．05）。结论乳腺癌保乳手术后，X射线调强放疗较电子线二维放疗在瘤床补量治疗上有更好的肿瘤局部控制率，但对患者生存无明显影响。

英文摘要：

Objective To compare the survival effects between using electron beams （EB） and modulated X-ray beams （XB） for boosting irradiation in breast cancer patients after breast-conserving surgery and postoperative radiotherapy. Methods This study retrospectively included 485 breast cancer patients who underwent breast-conserving surgery at Beijing Cancer Hospital. All patients underwent either EB or XB for tumor bed boost irradiation （ 10 - 16 Gy/5 - 8 fractions） after whole-breast irradiation of 46-50 Gy/23 -25 fractions. Results Median follow-up time for the cohort was 96. 04 months. Statistically significant increase of local recurrence free Survivai （LRFS） was observed in XB group than in EB group. The 5-year and 10-year LRFS was both 98.4% in XB group, as well as 94.2% and 93.2% in EB group, respectively （x^2 = 4. 190, P 〈 0.05 ）. But there was not statistically significant difference in 5-year and 10-year overall survival （OS） between XB group（96. 7% and 95.8% ）and EB group（94.9% and 89.4% ）, respectively （P 〉 0.05 ）. The multivariate analysis showed that LRFS was significantly correlated with age≤40, positive pathological lymph nodes and positive expression of Her-2 receptor. But boost irradiation method was not independent prognostic factor for LRFS and OS （ P 〉 0.05）. Conclusions For cancer patients treated with breast-conserving surgery and whole-breast postoperative radiation followed by a boost irradiation to tumor bed, XB irradiation was superior to EB irradiation in term of LRFS, yet no difference of OS was observed in both groups.