Kim Kyung Hwan, Noh Jae Myoung, Kim Yong Bae, Chang Jee Suk, Keum Ki Chang, Huh Seung Jae, Choi Doo Ho, Park Won, Suh Chang-Ok
Department of Radiation Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul, 120-752, Republic of Korea.
Breast Cancer Res Treat. 2015 Aug;152(3):589-99. doi: 10.1007/s10549-015-3505-1. Epub 2015 Jul 23.
The purpose of this study is to assess the value of internal mammary node irradiation (IMNI) in patients receiving postoperative radiotherapy after neoadjuvant chemotherapy (NAC) using modern systemic therapy. Between 2001 and 2009, 521 consecutive patients with clinical stage II-III breast cancer received NAC and postoperative radiotherapy. With a consistent policy, the treating radiation oncologist either included (N = 284) or excluded (N = 237) the internal mammary node in the treatment volume. Anthracycline- and taxane-based chemotherapy was provided to 482 (92.5 %) patients. To account for the unbalanced characteristics between the two groups, we performed propensity score matching and covariate adjustment using the propensity score. The median follow-up duration was 71 months (range 31-153 months). The 5-year disease-free survival (DFS) with and without IMNI was 81.8 and 72.7 %, respectively (p = 0.019). The benefit of IMNI varied according to patient characteristics such that it was more apparent in patients with N1-2 disease, inner/central location, and triple-negative subtype. After adjusting for all potential confounding variables, IMNI was independently associated with improved DFS (p = 0.049). The significant effect of IMNI on DFS was sustained after propensity score matching (p = 0.040) and covariate adjustment using the propensity score (p = 0.048). Symptomatic radiation pneumonitis developed in 9 (3.2 %) patients receiving IMNI. Our results indicated that IMNI was associated with a significant improvement in DFS with low toxicity rate for breast cancer patients receiving NAC. Further prospective studies are warranted to confirm the effect of IMNI in the NAC setting.
本研究的目的是评估在接受新辅助化疗（NAC）后采用现代全身治疗进行术后放疗的患者中，内乳淋巴结照射（IMNI）的价值。2001年至2009年期间，521例连续的临床II-III期乳腺癌患者接受了NAC和术后放疗。按照一致的策略，治疗放疗肿瘤学家将内乳淋巴结纳入（N = 284）或排除（N = 237）在治疗靶区内。482例（92.5%）患者接受了基于蒽环类和紫杉类的化疗。为了考虑两组之间不均衡的特征，我们使用倾向评分进行倾向评分匹配和协变量调整。中位随访时间为71个月（范围31 - 153个月）。接受和未接受IMNI的患者5年无病生存率（DFS）分别为81.8%和72.7%（p = 0.019）。IMNI的获益因患者特征而异，在N1 - 2期疾病、内侧/中央部位以及三阴性亚型的患者中更明显。在调整所有潜在混杂变量后，IMNI与DFS改善独立相关（p = 0.049）。在倾向评分匹配（p = 0.040）和使用倾向评分进行协变量调整（p = 0.048）后，IMNI对DFS的显著影响仍然存在。9例（3.2%）接受IMNI的患者发生了有症状的放射性肺炎。我们的结果表明，对于接受NAC的乳腺癌患者，IMNI与DFS的显著改善相关且毒性率低。有必要进行进一步的前瞻性研究以证实IMNI在NAC背景下的效果。
