Department of Oncology, Experimental Radiation Oncology, KU Leuven-University of Leuven, 3000, Leuven, Belgium.
Department of Radiation Oncology, University Hospitals Leuven, Herestraat 49, 3000, Leuven, Belgium.
Strahlenther Onkol. 2019 Apr;195(4):310-317. doi: 10.1007/s00066-018-1413-0. Epub 2019 Jan 2.
Adding a tumour bed boost to whole-breast irradiation in breast-conserving therapy reduces local recurrence rates. The purpose of the present study was to investigate whether the boost technique influences the magnitude of the effect.
Patients treated with breast-conserving therapy for invasive breast cancer between 2000 and 2007 were included in the analysis. Three groups were considered according to the applied boost technique: electrons, brachytherapy or photons. The endpoints were local recurrence and any recurrence. Cox regression models were used and correction for the confounders in the association between boost technique and outcome was performed using multivariable models.
1879 tumours were included in the analysis. 1448 tumours (77.1%) were treated with an electron boost, 334 (17.8%) with a brachytherapy boost and 97 (5.2%) with a photon boost. Median follow-up was 13.1 years. The 10-year local recurrence rate was 2.2%. In multivariable analysis with correction for age, pathological Tumour or Node stage (pT, pN), chemotherapy and hormonal therapy, there was no significant difference between the three groups for the local recurrence risk (p = 0.89). 10-year any recurrence rate was 10.8%. In multivariable analysis with correction for age, pT, pN, resection margins, radiotherapy, year of diagnosis, chemotherapy and hormonal therapy, there was no significant difference between the brachytherapy group and the electron group or the photon group (p = 0.11 and p = 0.28, respectively). The photon group had more recurrences compared to the electron group (Hazard Ratio 1.81, 95% Confidence Interval 1.12; 2.92, p = 0.02).
The local recurrence risk reduction of the tumour bed boost in breast-conserving therapy is not influenced by the applied boost technique.
在保乳治疗中加入肿瘤床加量放疗可降低局部复发率。本研究的目的是探讨加量放疗技术是否会影响这种效果的程度。
分析了 2000 年至 2007 年间接受保乳治疗的浸润性乳腺癌患者。根据应用的加量放疗技术，将患者分为三组：电子线、近距离放疗或光子线。终点为局部复发和任何复发。采用 Cox 回归模型，并使用多变量模型对加量放疗技术与结局之间的混杂因素进行校正。
共纳入 1879 个肿瘤。1448 个肿瘤（77.1%）采用电子线加量放疗，334 个肿瘤（17.8%）采用近距离放疗加量放疗，97 个肿瘤（5.2%）采用光子线加量放疗。中位随访时间为 13.1 年。10 年局部复发率为 2.2%。多变量分析校正年龄、病理肿瘤或淋巴结分期（pT、pN）、化疗和激素治疗后，三组间局部复发风险无显著差异（p=0.89）。10 年任何复发率为 10.8%。多变量分析校正年龄、pT、pN、切缘、放疗、诊断年份、化疗和激素治疗后，近距离放疗组与电子线组或光子线组间无显著差异（p=0.11 和 p=0.28）。与电子线组相比，光子线组的复发率更高（风险比 1.81，95%置信区间 1.12-2.92，p=0.02）。
保乳治疗中肿瘤床加量放疗降低局部复发率的效果不受应用的加量放疗技术的影响。
