Radiotherapy Oncology Department, Humanitas-Istituto Clinico Catanese, Misterbianco (CT), Italy.
Fondazione Policlinico Universitario A. Gemelli IRCCS, UOC di Radioterapia, Dipartimento di Scienze Radiologiche, Radioterapiche Ed Ematologiche, Roma, Italy.
Breast. 2021 Feb;55:119-127. doi: 10.1016/j.breast.2020.12.012. Epub 2021 Jan 2.
To perform a meta-analysis to determine the effect of loco-regional radiation therapy (RT) compared to no loco-regional RT for operated patients in clinical stage cN2 breast cancer at diagnosis and ypN0 after preoperative chemotherapy (PST).
Eligible studies were identified through a systematic search of the medical literature performed independently by two researchers using a validated search strategy. An electronic search of Medline via PubMed and Embase (Breast cancer AND preoperative chemotherapy AND radiation therapy) was conducted with no language or publication status restrictions. The effect of loco-regional RT on overall (OS), disease free (DFS), loco-regional recurrence-free (LRRFS) survival and local recurrence was evaluated. An electronic search of Medline via PubMed and Embase (Toxicity AND radiation therapy breast cancer AND preoperative therapy; toxicity AND breast surgery AND preoperative chemotherapy) was conducted for outcomes of harm: major acute and late skin toxicity, lymphedema and cardiac events.
Of 333 studies identified, 4 retrospective studies reporting on a total of 1107 patients were included in the meta-analysis. Six and 3 reported data of acute and late skin toxicity, while 2 studies provided information on cardiac events. Pooled results showed no difference in terms of hazard ratio for loco-regional RT versus no loco-regional RT [hazard ratio (HR) = 0.82, 95% confidence interval (CI) 0.63-1.68]. Loco-regional RT was associated with an OS benefit in the subgroup analysis: IIIB-C (loco-regional RT 79.3% vs no loco-regional RT 71.2%, p = 0.027) and T3-T4 (loco-regional RT 82.6% vs no loco-regional RT 76.6%, p = 0.025). No difference was shown in terms of 5-year DFS (loco-regional RT 91.2% vs no loco-regional RT 83%, p = 0.441) and LRRFS (loco-regional RT 98.1% vs no loco-regional RT 92.3%, p = 0.148). There was no significant difference between the groups in terms of acute and late skin toxicities, lymphedema and cardiac events.
Because of the limitations due to the small number of studies and heterogeneity in the analysis, the present study does not allow to draw any definitive conclusion, highlighting the need for well-controlled trials to determine the effect of loco-regional RT in patients with cN2 having a pathological complete response in the axillary nodes after preoperative chemotherapy.
进行荟萃分析，以确定对于术前化疗后腋窝淋巴结病理完全缓解的 cN2 乳腺癌患者，与未行局部区域放疗相比，行局部区域放疗的效果。
两名研究人员通过系统搜索医学文献，独立使用经过验证的搜索策略确定了合格的研究。通过 Medline 上的 PubMed 和 Embase 进行了针对“乳腺癌和术前化疗和放疗”的电子检索，无语言或出版状态限制。评估了局部区域放疗对总生存（OS）、无病生存（DFS）、局部区域无复发生存（LRRFS）和局部复发的影响。通过 Medline 上的 PubMed 和 Embase 进行了针对“毒性和乳腺癌放疗和术前治疗；毒性和乳房手术和术前化疗”的电子检索，以获取危害结局的信息：主要急性和晚期皮肤毒性、淋巴水肿和心脏事件。
在 333 项研究中，有 4 项回顾性研究共报告了 1107 例患者，纳入荟萃分析。其中 6 项和 3 项报告了急性和晚期皮肤毒性的数据，而 2 项研究提供了心脏事件的信息。汇总结果显示，局部区域放疗与无局部区域放疗的局部区域复发风险比无显著差异[风险比（HR）=0.82，95%置信区间（CI）0.63-1.68]。局部区域放疗与 OS 获益相关：IIIB-C 期（局部区域放疗 79.3%，无局部区域放疗 71.2%，p=0.027）和 T3-T4 期（局部区域放疗 82.6%，无局部区域放疗 76.6%，p=0.025）。5 年 DFS（局部区域放疗 91.2%，无局部区域放疗 83%，p=0.441）和 LRRFS（局部区域放疗 98.1%，无局部区域放疗 92.3%，p=0.148）方面两组无差异。两组之间的急性和晚期皮肤毒性、淋巴水肿和心脏事件无显著差异。
由于研究数量少且分析存在异质性，本研究无法得出明确结论，强调需要进行良好对照的试验来确定局部区域放疗对术前化疗后腋窝淋巴结病理完全缓解的 cN2 患者的效果。
