PDF(Pubmed)
Abstract：
BACKGROUND: The use of locoregional radiotherapy (RT) in patients with advanced ER-positive, HER2-negative breast cancer remains a topic of ongoing debate. In this study, we aimed to evaluate the efficacy of locoregional RT in advanced breast cancer patients treated with cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) in a first-line setting.
METHODS: We conducted a retrospective analysis of patients diagnosed with advanced breast cancer between 2018 and 2023 who received treatment with CDK4/6i and underwent locoregional radiotherapy.
RESULTS: Among the 371 patients treated with CDK4/6i as part of their first-line therapy, 23 received locoregional RT either concurrently or sequentially with CDK4/6 inhibitors. Disease progression within the breast occurred in 19 patients (5.1%). Among these cases, five patients had previously undergone breast RT (5/23, 21.7%), while 14 did not (14/348, 4.0%, p = 0.004). All cases of local progression after RT followed palliative doses and were accompanied by early systemic progression. The 2-year PFS in the entire cohort of patients treated with locoregional RT was 65.7% (95% CI: 40.5-82.3%). Notably, patients who received higher RT doses had longer 2-year PFS (83.3%, 95% CI: 27.3-97.5%) than those with palliative RT doses (59.3%, 95% CI: 30.7-79.3%); however, the results were not statistically significant (p = 0.58). Furthermore, the 2-year local control in the entire cohort with locoregional RT was 73.0% (95% CI: 46.5-87.9%). Importantly, no local progression was observed after RT when using high doses.
CONCLUSIONS: The addition of locoregional radiotherapy to first-line CDK4/6 inhibitors warrants further investigation across various clinical scenarios in advanced breast cancer. Palliative radiation regimens delivered early in breast oligoprogression may not always suffice, emphasizing the need for comprehensive studies in this context.
METHODS: We conducted a retrospective analysis of patients diagnosed with advanced breast cancer between 2018 and 2023 who received treatment with CDK4/6i and underwent locoregional radiotherapy.
RESULTS: Among the 371 patients treated with CDK4/6i as part of their first-line therapy, 23 received locoregional RT either concurrently or sequentially with CDK4/6 inhibitors. Disease progression within the breast occurred in 19 patients (5.1%). Among these cases, five patients had previously undergone breast RT (5/23, 21.7%), while 14 did not (14/348, 4.0%, p = 0.004). All cases of local progression after RT followed palliative doses and were accompanied by early systemic progression. The 2-year PFS in the entire cohort of patients treated with locoregional RT was 65.7% (95% CI: 40.5-82.3%). Notably, patients who received higher RT doses had longer 2-year PFS (83.3%, 95% CI: 27.3-97.5%) than those with palliative RT doses (59.3%, 95% CI: 30.7-79.3%); however, the results were not statistically significant (p = 0.58). Furthermore, the 2-year local control in the entire cohort with locoregional RT was 73.0% (95% CI: 46.5-87.9%). Importantly, no local progression was observed after RT when using high doses.
CONCLUSIONS: The addition of locoregional radiotherapy to first-line CDK4/6 inhibitors warrants further investigation across various clinical scenarios in advanced breast cancer. Palliative radiation regimens delivered early in breast oligoprogression may not always suffice, emphasizing the need for comprehensive studies in this context.
摘要：
背景：在晚期ER阳性患者中使用局部放疗（RT），HER2阴性乳腺癌仍然是一个正在进行辩论的话题。在这项研究中,我们的目的是评估局部区域RT在接受细胞周期蛋白依赖性激酶4/6抑制剂(CDK4/6i)一线治疗的晚期乳腺癌患者中的疗效.
方法：我们对2018年至2023年接受CDK4/6i治疗并接受局部放疗的晚期乳腺癌患者进行了回顾性分析。
结果：在接受CDK4/6i作为一线治疗的371例患者中，23与CDK4/6抑制剂同时或依次接受局部RT。19例患者发生乳腺内疾病进展（5.1%）。在这些案例中,5例患者先前接受过乳腺RT（5/23，21.7%），而14个没有(14/348，4.0%，p=0.004)。所有在RT后局部进展的病例都遵循姑息剂量，并伴有早期全身进展。在接受局部区域RT治疗的患者的整个队列中，2年PFS为65.7％（95％CI：40.5-82.3％）。值得注意的是,接受较高剂量RT的患者2年PFS较长（83.3%，95％CI：27.3-97.5％）比那些姑息性RT剂量（59.3％，95%CI：30.7-79.3%)；然而，结果无统计学意义(p=0.58).此外，在使用局部RT的整个队列中,2年局部控制为73.0%(95%CI:46.5-87.9%).重要的是,当使用高剂量时,RT后未观察到局部进展.
结论：在一线CDK4/6抑制剂中添加局部放疗值得在晚期乳腺癌的各种临床方案中进一步研究。在乳房少进展早期实施姑息性放疗方案可能并不总是足够的，强调在这方面进行全面研究的必要性。
方法：我们对2018年至2023年接受CDK4/6i治疗并接受局部放疗的晚期乳腺癌患者进行了回顾性分析。
结果：在接受CDK4/6i作为一线治疗的371例患者中，23与CDK4/6抑制剂同时或依次接受局部RT。19例患者发生乳腺内疾病进展（5.1%）。在这些案例中,5例患者先前接受过乳腺RT（5/23，21.7%），而14个没有(14/348，4.0%，p=0.004)。所有在RT后局部进展的病例都遵循姑息剂量，并伴有早期全身进展。在接受局部区域RT治疗的患者的整个队列中，2年PFS为65.7％（95％CI：40.5-82.3％）。值得注意的是,接受较高剂量RT的患者2年PFS较长（83.3%，95％CI：27.3-97.5％）比那些姑息性RT剂量（59.3％，95%CI：30.7-79.3%)；然而，结果无统计学意义(p=0.58).此外，在使用局部RT的整个队列中,2年局部控制为73.0%(95%CI:46.5-87.9%).重要的是,当使用高剂量时,RT后未观察到局部进展.
结论：在一线CDK4/6抑制剂中添加局部放疗值得在晚期乳腺癌的各种临床方案中进一步研究。在乳房少进展早期实施姑息性放疗方案可能并不总是足够的，强调在这方面进行全面研究的必要性。
