Research Oncology, Division of Cancer Studies, King's College London, Guy's Hospital, London, UK; Department of Breast Surgery, Istituto Nazionale per lo Studio e la cura dei tumori 'Fondazione Giovanni Pascale' - IRCCS, Naples, Italy.
Br J Surg. 2015 May;102(6):599-610. doi: 10.1002/bjs.9781. Epub 2015 Mar 17.
Intraoperative radiotherapy (IORT) constitutes a paradigm shift from the conventional 3-5 weeks of whole-breast external beam radiotherapy (EBRT). IORT enables delivery of radiation at the time of excision of the breast tumour, targeting the area at highest risk of recurrence, while minimizing excessive radiation exposure to healthy breast tissue. The rationale for IORT is based on the observation that over 90 per cent of local recurrences after breast-conserving surgery occur at or near the original operation site.
This article reviews trials of IORT delivered with different techniques and devices.
IORT is a very attractive option for delivering radiotherapy, reducing the traditional fractionated treatment to a single fraction administered at the time of surgery. IORT has been shown to be associated with reduced toxicity and has several potential benefits over EBRT. Only two randomized clinical trials have been published to date. The TARGIT-A and ELIOT trials have demonstrated that IORT is associated with a low rate of local recurrence, although higher than that after EBRT (TARGIT-A: 3·3 versus 1·3 per cent respectively, P = 0·042; ELIOT: 4·4 versus 0·4 per cent, P < 0·001). However, the local recurrence rate for IORT fell within the predefined 2·5 per cent non-inferiority margin in TARGIT-A, and the 7·5 per cent equivalence margin in ELIOT.
Longer follow-up data from existing trials, optimization of patient criteria and cost-effectiveness analyses are needed. Based on the current evidence, IORT can be offered as an alternative to EBRT to selected patients within agreed protocols, and outcomes should be monitored within national registries.
术中放疗（IORT）代表了从传统的 3-5 周全乳外照射放疗（EBRT）的范式转变。IORT 使我们能够在切除乳房肿瘤时提供放射治疗，靶向复发风险最高的区域，同时最大限度地减少对健康乳房组织的过度辐射暴露。IORT 的基本原理基于这样的观察：保乳手术后超过 90%的局部复发发生在或靠近原始手术部位。
本文回顾了使用不同技术和设备进行的 IORT 试验。
IORT 是一种非常有吸引力的放疗选择，将传统的分次治疗减少到手术时单次给予。IORT 已被证明与毒性降低有关，并且与 EBRT 相比具有几个潜在的优势。迄今为止，仅发表了两项随机临床试验。TARGIT-A 和 ELIOT 试验表明，IORT 与局部复发率降低相关，尽管高于 EBRT（TARGIT-A：分别为 3.3%和 1.3%，P=0.042；ELIOT：4.4%和 0.4%，P<0.001）。然而，TARGIT-A 中 IORT 的局部复发率落在预设的 2.5%非劣效性边界内，而在 ELIOT 中落在 7.5%等效性边界内。
需要从现有试验中获得更长的随访数据、优化患者标准和成本效益分析。基于目前的证据，IORT 可以作为 EBRT 的替代方案，为符合协议的选定患者提供，并应在国家登记处监测结果。
