与术后 PBI 相比，术前部分乳腺照射 (PBI) 可以提高目标体积定义的准确性并减少照射体积。在 ABLATIVE 试验 (NCT02316561) 中，15/36 名患者在术前 PBI 和保乳手术 (BCS) 后 6-8 个月达到病理完全缓解 (pCR)。我们现在公布 5 年结果。ABLATIVE 试验是在荷兰四家医院进行的一项前瞻性队列研究。 2015 年至 2018 年间，患有单灶性非小叶乳腺癌、ER 阳性、HER2 阴性和肿瘤阴性前哨淋巴结的年龄≥ 50 岁的女性接受术前单剂量 PBI 治疗，随后在六或八个月后接受 BCS 治疗。主要终点是 pCR。次要终点是每年评估肿瘤学结果、毒性、美容结果（由患者和医生评估）和生活质量。36 名患者在 PBI 后 6 个月 (n=15) 和 8 个月 (n=21) 接受 BCS 治疗。肿瘤大小中位数为 13 毫米 (IQR 9-16)。中位随访 5.5 年（IQR 5.1-6.0 年）后，两名 (6%) 患者出现同侧乳房事件和两名 (6%) 远处转移。 5 年总生存率为 94% [95% CI 87-100%]。临床医生报告的 1/2 级乳腺纤维化和乳房不适/疼痛的 5 年累积发生率分别为 94%/6% 和 75%/6%。对美容结果（非常）满意的患者比例在基线时为 89%，在 5 年时为 78%。使用 BCCT.core 软件评估的所有患者的美容效果均为优秀或良好。 4 年中位全球生活质量评分为 83 (IQR 67-92)，与基线相似 (83 (IQR 75-83)，p=0.42)。术前单剂量 PBI 和 BCS 可能是一种肿瘤学上安全的治疗方法轻度晚期毒性，5 年随访期间美容效果和生活质量没有下降。这意味着术前照射代替标准术后照射有可能挑战当前的临床实践。版权所有 © 2024。由 Elsevier Inc. 出版。

Preoperative partial breast irradiation (PBI) can increase accuracy of target volume definition and decrease irradiated volumes compared with postoperative PBI. In the ABLATIVE trial (NCT02316561), 15/36 patients achieved pathologic complete response (pCR) 6-8 months after preoperative PBI and breast conserving surgery (BCS). We now present the 5-year results.The ABLATIVE trial is a Dutch prospective cohort study in four hospitals. Women aged ≥ 50 years with unifocal, non-lobular breast cancer, ER-positive, HER2-negative, and a tumor negative sentinel node were treated between 2015-2018 with preoperative single-dose PBI followed by BCS after six or eight months. The primary endpoint was pCR. Secondary endpoints were yearly evaluated oncological outcomes, toxicity, cosmetic outcome (assessed by patients and physicians) and quality of life.Thirty-six patients were treated with BCS six (n=15) and eight (n=21) months following PBI. Median tumor size was 13 mm (IQR 9-16). After a median follow-up of 5.5 years (IQR 5.1-6.0 years), two (6%) patients had ipsilateral breast events and two (6%) distant metastases. The 5-years overall survival was 94% [95% CI 87-100%]. The 5-year cumulative incidence of clinician-reported grade 1/2 breast fibrosis and breast discomfort/pain were 94%/6% and 75%/6%, respectively. The proportion of patients (very) satisfied with the cosmetic results was 89% at baseline and 78% at 5 years. Cosmetic results evaluated using the BCCT.core software were excellent or good in all patients. The 4-year median global quality of life score was 83 (IQR 67-92), similar to baseline (83 (IQR 75-83), p=0.42).Preoperative single-dose PBI and BCS may be an oncologically safe treatment with mild late toxicity, and no decline in cosmetic results and quality of life during 5 years of follow-up. This means that preoperative instead of standard postoperative irradiation has the potential to challenge the current clinical practice.Copyright © 2024. Published by Elsevier Inc.