■外束放射治疗(EBRT),保乳手术(BCS)的辅助治疗,需要很长的治疗时间,是昂贵的,并伴有许多并发症。长期随访的大样本研究缺乏关于术中放疗(IORT)一种新兴的放射治疗模式,对于用BCS治疗无淋巴结转移的T1-2早期乳腺癌患者,可以替代EBRT。
■我们在2000年至2018年的监测中确定了270,842例T1-2N0M0乳腺癌患者,流行病学,和结束结果(SEER)数据库。共有10,992例患者通过倾向评分匹配(PSM)进行匹配。根据放射治疗方法,将患者分为IORT组和EBRT组。通过Kaplan-Meier分析,分析并比较IORT组和EBRT组之间的总生存率(OS)和乳腺癌特异性生存率(BCSS)。双侧P<0.05被认为是显著的。
■PSM后,生存分析显示,IORT组和EBRT组的OS或BCSS率无显著差异.在亚组分析中,2010年至2013年诊断的IORT人群(HR=0.675,95%CI0.467-0.976,P=0.037)或T2期(HR=0.449,95%CI0.261-0.772,P=0.004)具有较好的OS率,但是在总人口中,T1期患者的OS和BCSS率优于T2期患者(P<0.0001),T2期化疗比例明显高于T1期。雌激素受体未知的EBRT患者的OS率较高(HR=3.392,95%CI1.368-8.407,P=0.008)。此外,IORT组已婚患者的BCSS率较高(HR=0.403,95%CI0.184-0.881,P=0.023),III级(HR=0.405,95%CI0.173-0.952,P=0.038),与EBRT组相比,接受化疗的乳腺癌患者(HR=0.327,95%CI0.116-0.917,P=0.034)。
■非劣质OS和BCSS率的术中放疗结果,与EBRT相比,在BCS治疗的无淋巴结转移的早期乳腺癌患者中,和IORT作为标准治疗的有效替代方案可能为患者提供实质性益处。这一发现为早期乳腺癌的放射治疗策略提供了新的见解。
UNASSIGNED: External beam radiotherapy (EBRT), an adjuvant to breast-conserving surgery (BCS), requires a long treatment period, is costly, and is associated with numerous complications. Large sample studies with long follow-up periods are lacking regarding whether intraoperative radiotherapy (IORT), an emerging radiotherapy modality, can replace EBRT for patients with T1-2 early stage breast cancer without lymph node metastasis treated with BCS.
UNASSIGNED: We identified 270,842 patients with T1-2N0M0 breast cancer from 2000 to 2018 in the Surveillance, Epidemiology, and End Results (SEER) database. A total of 10,992 patients were matched by propensity score matching (PSM). According to the radiotherapy method, the patients were divided into the IORT and EBRT groups. Overall survival (OS) and breast cancer-specific survival (BCSS) rates were analyzed and compared between the IORT and EBRT groups by Kaplan-Meier analysis. Bilateral P < 0.05 was considered to indicate significance.
UNASSIGNED: After PSM, the survival analysis showed no significant differences in OS or BCSS rates between the IORT and EBRT groups. In the subgroup analysis, the IORT population diagnosed from 2010 to 2013 (HRs = 0.675, 95% CI 0.467-0.976, P = 0.037) or with T2 stage (HRs = 0.449, 95% CI 0.261-0.772, P = 0.004) had better OS rates, but in the overall population, the OS and BCSS rates were better in patients with T1 stage than in patients with T2 stage (P < 0.0001), and the proportion of chemotherapy was significantly higher in T2 stage than in T1 stage. Patients who had EBRT with unknown estrogen receptor had better OS rates (HRs = 3.392, 95% CI 1.368-8.407, P = 0.008). In addition, the IORT group had better BCSS rates for married (HRs = 0.403, 95% CI 0.184-0.881, P = 0.023), grade III (HRs = 0.405, 95% CI 0.173-0.952, P = 0.038), and chemotherapy-receiving (HRs = 0.327, 95% CI 0.116-0.917, P = 0.034) patients with breast cancer compared to the EBRT group.
UNASSIGNED: Intraoperative radiotherapy results of non-inferior OS and BCSS rates, compared to those of EBRT, in patients with early stage breast cancer without lymph node metastasis treated with BCS, and IORT may provide substantial benefits to patients as an effective alternative to standard treatment. This finding provides new insights into radiotherapy strategies for early stage breast cancer.