Division of Radiation Oncology and Developmental Radiotherapeutics, University of British Columbia, Vancouver, BC, Canada.
Int J Radiat Oncol Biol Phys. 2011 Jun 1;80(2):403-9. doi: 10.1016/j.ijrobp.2010.02.041. Epub 2010 Jun 26.
To determine whether the adjuvant breast cancer radiation volume or fraction size (>2 Gy vs. ≤2 Gy) affected the risk of fatal cardiac or cerebrovascular (CCV) events and to determine whether the addition of regional radiotherapy (RT) increased the risk of fatal cerebrovascular events compared with breast/chest wall RT alone.
Overall survival was compared for patients receiving breast/chest wall RT alone or breast/chest wall plus regional node RT (BRCW+NRT) in a population-based cohort of women with early-stage breast cancer who had undergone RT between 1990 and 1996. The effect of laterality, age, systemic therapy, radiation volume, and fraction size on the risk of fatal CCV events was analyzed using a competing risk method.
A total of 4,929 women underwent adjuvant RT. The median follow-up was 11.7 years. BRCW+NRT was associated with an increased risk of CCV death at 12 years (5% for BRCW+NRT vs. 3.5% for breast/chest wall RT alone; p = .004), but the fraction size was not (3.92% for a fraction size >2 Gy vs. 3.54% for a fraction size <2 Gy; p = .83). The 12-year absolute risk of death from stroke alone did not differ for either radiation volume (1.17% for BRCW+NRT vs. 0.8% for breast/chest wall RT alone; p = .22) or fraction size (p = .59).
Regional RT was associated with a small (1.5% at 12 years), but statistically significant, increased risk of death from a CCV event. The addition of regional RT did not significantly increase the risk of death from stroke, although the number of events was small. An increased fraction size was not significantly associated with a greater risk of fatal CCV events. These data support the continued use of hypofractionated adjuvant regional RT.
确定辅助乳腺癌放疗体积或分次剂量（>2Gy 与≤2Gy）是否会影响致命性心脑血管（CCV）事件的风险，并确定与单纯乳腺/胸壁放疗（BRCW+NRT）相比，区域放疗（RT）的加入是否会增加致命性脑血管事件的风险。
对 1990 年至 1996 年间接受辅助放疗的早期乳腺癌女性进行了基于人群的队列研究，比较了仅接受乳腺/胸壁放疗（BRCW+NRT）或乳腺/胸壁加区域淋巴结放疗（BRCW+NRT）的患者的总生存率。使用竞争风险方法分析了侧别、年龄、全身治疗、放疗体积和分次剂量对致命性 CCV 事件风险的影响。
共有 4929 名女性接受了辅助放疗。中位随访时间为 11.7 年。BRCW+NRT 与 12 年时 CCV 死亡风险增加相关（BRCW+NRT 为 5%，BRCW+NRT 为 3.5%；p=0.004），但分次剂量无关（分次剂量>2Gy 为 3.92%，分次剂量<2Gy 为 3.54%；p=0.83）。BRCW+NRT 与单纯乳腺/胸壁 RT 相比，12 年时单独死于卒中的绝对风险无差异（BRCW+NRT 为 1.17%，单纯乳腺/胸壁 RT 为 0.8%；p=0.22），或分次剂量（p=0.59）。
区域 RT 与较小（12 年时为 1.5%）但具有统计学意义的 CCV 事件死亡风险增加相关。尽管事件数量较少，但区域 RT 的加入并未显著增加卒中死亡的风险。增加分次剂量与致命性 CCV 事件的风险增加无显著相关性。这些数据支持继续使用低分割辅助区域 RT。
