Is Intraoperative Radiotherapy a Standard Technique for Early Breast Cancer?

Recently, two pivotal papers with Intraoperative radiotherapy (IORT) are published [1,2]. The standard treatment for early breast cancer is breast-conserving therapy (BCT) with whole breast external irradiation therapy (WBI) [3]. Even in highly selected patients, omission of radiotherapy increases the risk of local recurrence [4]. In actuality some women are still encouraged to proceed to mastectomy, because of the lack of access to radiotherapy centers or the long course of treatment of WBI. Then shorter treatment option of irradiation is needed, Partial breast irradiation (PBI) has been tested in clinical trials for selected patients. The rationale for PBI is that local recurrences after BCT with or without WBI arise most in the same quadrant as the primary cancer [5]. The main objective of radiotherapy after BCT is considered to be the destruction of residual cancer cells in the operative field. PBI administered around the tumor bed has been comparable to WBI in selected patients in phase II studies [6-9]. Adequate local control, minimal toxicity, and good cosmetic appearance are shown in studies of PBI [10]. IORT is one of these PBI methods, makes it possible to remove the need to attend a radiotherapy center for 25 fractions for WBI. At present, outside the setting of a clinical trial, use of IORT as well as PBI has not been recommended yet [10,11]. They had been remained investigational until the information of phase III on its long-term efficacy compared with WBI and safety becomes available [12], although more than 1,000 IORT procedures were used in the Milan Institute [13,14].