Kolberg Hans-Christian, Loevey Gyoergy, Akpolat-Basci Leyla, Stephanou Miltiades, Fasching Peter A, Untch Michael, Bulsara Max, Vaidya Jayant S, Liedtke Cornelia
Department of Gynecology and Obstetrics, Marienhospital Bottrop gGmbH, Josef-Albers-Str. 70, 46236 Bottrop, Germany.
BORAD, Neustr. 17a, 46236 Bottrop, Germany.
Rev Recent Clin Trials. 2017;12(2):93-100. doi: 10.2174/1574887112666170201142458.
Targeted intraoperative radiotherapy (TARGIT - IORT) as a tumour bed boost after breast conserving surgery is well established for women with early breast cancer. A previous study from our group shows a beneficial effect of TARGIT-IORT on overall survival (OS) but not disease-free survival (DFS) after neoadjuvant chemotherapy compared to an external boost suggesting a potential non-inferiority of TARGIT-IORT. In this study, we present results regarding the high-risk subset of patients (i.e. with triple negative (TN) and HER2 positive tumours) from this cohort.
In this non-randomized cohort study involving patients with HER2 positive (n= 28) and triple negative (n=42) tumours after NACT we compared outcomes of 40 patients with tumour bed boost applied with TARGIT IORT during lumpectomy versus 30 patients treated in the previous 13 months with external (EBRT) boost. All patients received whole breast radiotherapy. Rates of DFS and OS were compared.
Median follow up was 49 months. In comparison of TARGIT-IORT vs. EBRT 5-year Kaplan- Meier estimates of OS showed no significant difference among patients with HER2 positive tumours (100% vs. 91.7%, log rank p = 0.22). The same was seen for DFS (83.3% vs. 77.0%, log rank p=0.38). The results for TN cases were similar (OS : 87.5% vs. 74.1%, log rank p=0.488; DFS 87.5% vs. 60%, log rank p=0.22).
Although survival estimates trended towards favouring TARGIT-IORT, no significant differences could be observed and the significantly positive result for OS favoring TARGIT-IORT in the whole cohort of 116 patients could not be reproduced in this subset analysis of patients with TN and HER2 positive tumours. This may be contributable to the limited number of patients but may also indicate that effects seen in the whole cohort were mainly driven by ER and/or PR positive and HER2 negative tumours. Most importantly, non-inferiority of TARGIT-IORT as an intraoperative boost could be reproduced in these high-risk patients.
对于早期乳腺癌女性患者，保乳手术后采用靶向术中放疗（TARGIT - IORT）作为瘤床加量放疗已得到充分认可。我们团队之前的一项研究表明，与外照射加量放疗相比，新辅助化疗后TARGIT - IORT对总生存期（OS）有有益影响，但对无病生存期（DFS）无影响，提示TARGIT - IORT可能具有非劣效性。在本研究中，我们展示了该队列中高危患者亚组（即三阴性（TN）和HER2阳性肿瘤患者）的相关结果。
在这项非随机队列研究中，纳入接受新辅助化疗后HER2阳性（n = 28）和三阴性（n = 42）肿瘤患者，我们比较了40例在肿块切除术中应用TARGIT IORT进行瘤床加量放疗的患者与前13个月接受外照射（EBRT）加量放疗的30例患者的结局。所有患者均接受全乳放疗。比较DFS和OS发生率。
中位随访时间为49个月。比较TARGIT - IORT与EBRT，HER2阳性肿瘤患者的5年Kaplan - Meier OS估计值无显著差异（100%对91.7%，对数秩检验p = 0.22）。DFS结果同样如此（83.3%对77.0%，对数秩检验p = 0.38）。TN病例的结果相似（OS：87.5%对74.1%，对数秩检验p = 0.488；DFS 87.5%对60%，对数秩检验p = 0.22）。
尽管生存估计值倾向于支持TARGIT - IORT，但未观察到显著差异，并且在这116例患者的整个队列中OS显著支持TARGIT - IORT的结果在TN和HER2阳性肿瘤患者的该亚组分析中未重现。这可能归因于患者数量有限，但也可能表明在整个队列中观察到的效应主要由雌激素受体（ER）和/或孕激素受体（PR）阳性且HER2阴性肿瘤驱动。最重要的是，TARGIT - IORT作为术中加量放疗的非劣效性在这些高危患者中得到了重现。
