Abstract：
OBJECTIVE: to evaluate the outcome of partial breast re-irradiation (re-PBI) with intensity modulated RT (IMRT), using a hypofractionated scheme for breast cancer (BC) local recurrence (LR) operated on with repeat breast-conserving surgery (re-BCS).
METHODS: IMRT-based re-PBI was performed using either helical or step-and-shoot modality to deliver 37.05 Gy in 13 fractions in 2.5 weeks. Cumulative incidence (CumI) of 2ndLR, toxicity, disease-free (DFS), BC specific (BCSS), and overall (OS) survival were evaluated.
RESULTS: Between 5/2012 and 5/2021, 70 patients had re-PBI. Median follow-up (FU) was 6.3 years (Q1-Q3, 4.0-8.1.). Median age at 1stLR was 62. The median primary BC-1stLR interval was 12.4 years (range: 1.6-26.7). Luminal A-like 1stLR accounted for 41% of the cases and median size was 0.8 cm. During FU, 18 (26%) patients showed a subsequent event: three 2snLRs (corresponding to 8-y Cumulative rate of 4%), 3 regional nodal recurrences, 7 distant metastases, and 5 other primary tumors. At 8 years, DFS, BCSS and OS were 76%, 90%, and 90%, respectively. At multivariate analysis, Grade 3 and extensive intraductal component were independent predictors for DFS. For 51 and 46 patients, chronic toxicity and cosmesis were evaluated, respectively: 4% had grade 3 fibrosis and cosmesis was deemed good/excellent in just over 60% of the cases.
CONCLUSIONS: Re-PBI after re-BCS represents a feasible alternative to mastectomy with regard to local control, showing an acceptable toxicity profile. A long-term FU is crucial to better understand the pattern of relapse and consolidate the position of re-PBI in clinical practice.
METHODS: IMRT-based re-PBI was performed using either helical or step-and-shoot modality to deliver 37.05 Gy in 13 fractions in 2.5 weeks. Cumulative incidence (CumI) of 2ndLR, toxicity, disease-free (DFS), BC specific (BCSS), and overall (OS) survival were evaluated.
RESULTS: Between 5/2012 and 5/2021, 70 patients had re-PBI. Median follow-up (FU) was 6.3 years (Q1-Q3, 4.0-8.1.). Median age at 1stLR was 62. The median primary BC-1stLR interval was 12.4 years (range: 1.6-26.7). Luminal A-like 1stLR accounted for 41% of the cases and median size was 0.8 cm. During FU, 18 (26%) patients showed a subsequent event: three 2snLRs (corresponding to 8-y Cumulative rate of 4%), 3 regional nodal recurrences, 7 distant metastases, and 5 other primary tumors. At 8 years, DFS, BCSS and OS were 76%, 90%, and 90%, respectively. At multivariate analysis, Grade 3 and extensive intraductal component were independent predictors for DFS. For 51 and 46 patients, chronic toxicity and cosmesis were evaluated, respectively: 4% had grade 3 fibrosis and cosmesis was deemed good/excellent in just over 60% of the cases.
CONCLUSIONS: Re-PBI after re-BCS represents a feasible alternative to mastectomy with regard to local control, showing an acceptable toxicity profile. A long-term FU is crucial to better understand the pattern of relapse and consolidate the position of re-PBI in clinical practice.
摘要：
目的：评估部分乳腺再照射（re-PBI）与调强放疗（IMRT）的结果，使用大分割方案治疗乳腺癌（BC）局部复发（LR），并进行重复保乳手术（re-BCS）。
方法：使用螺旋或分步方式进行基于IMRT的re-PBI，在2.5周内以13个部分递送37.05Gy。2ndLR的累积发病率（CumI），毒性,无病（DFS），BC特异性（BCSS），评估总生存率（OS）。
结果：在2012年5月5日至2021年5月5日之间，70例患者发生了PBI复发。中位随访时间（FU）为6.3年（Q1-Q3，4.0-8.1。).1stLR的中位年龄为62。原发性BC-1stLR间期中位数为12.4年（范围：1.6-26.7）。管腔A样1stLR占病例的41％，中位大小为0.8cm。FU期间,18例（26%）患者出现后续事件：3个2snLR（对应4％的8-y累积率），3个区域节点复发，7个远处转移，和其他5个原发性肿瘤。8年,DFS,BCSS和OS为76%，90%,90%,分别。在多变量分析中，3级和广泛的导管内成分是DFS的独立预测因子。对于51和46名患者，慢性毒性和美容进行了评估，分别为：4％的患者有3级纤维化，在超过60％的病例中，美容被认为是良好/优异的。
结论：就局部控制而言，re-BCS后的re-PBI是替代乳房切除术的可行方法。显示可接受的毒性特征。长期FU对于更好地了解复发模式和巩固re-PBI在临床实践中的地位至关重要。
方法：使用螺旋或分步方式进行基于IMRT的re-PBI，在2.5周内以13个部分递送37.05Gy。2ndLR的累积发病率（CumI），毒性,无病（DFS），BC特异性（BCSS），评估总生存率（OS）。
结果：在2012年5月5日至2021年5月5日之间，70例患者发生了PBI复发。中位随访时间（FU）为6.3年（Q1-Q3，4.0-8.1。).1stLR的中位年龄为62。原发性BC-1stLR间期中位数为12.4年（范围：1.6-26.7）。管腔A样1stLR占病例的41％，中位大小为0.8cm。FU期间,18例（26%）患者出现后续事件：3个2snLR（对应4％的8-y累积率），3个区域节点复发，7个远处转移，和其他5个原发性肿瘤。8年,DFS,BCSS和OS为76%，90%,90%,分别。在多变量分析中，3级和广泛的导管内成分是DFS的独立预测因子。对于51和46名患者，慢性毒性和美容进行了评估，分别为：4％的患者有3级纤维化，在超过60％的病例中，美容被认为是良好/优异的。
结论：就局部控制而言，re-BCS后的re-PBI是替代乳房切除术的可行方法。显示可接受的毒性特征。长期FU对于更好地了解复发模式和巩固re-PBI在临床实践中的地位至关重要。
