Could intraoperative radiotherapy replace standard irradiation treatments?

This study evaluated the effectiveness of intraoperative radiotherapy as an alternative to standard breast irradiation treatments.

Breast-conserving surgery followed by whole breast irradiation has become the standard of care in the treatment of small breast cancer tumors. Recent studies have demonstrated that the duration of irradiation can be shortened, and that partial breast irradiation may be employed to reduce the amount of healthy tissue being irradiated, both with similar rates of cancer recurrence.

Intraoperative radiotherapy, in which the tumor bed is given a single-dose of radiotherapy during surgery, is currently under investigation. Intraoperative single-dose radiotherapy is an appealing concept since the burden of multiple weekly treatments is spared. In addition, skin damage, a crucial factor in breast reconstruction, is largely avoided with intraoperative radiotherapy.

1305 women with early breast cancer were randomized to receive either breast conserving surgery followed by whole breast irradiation, or breast conserving surgery with intraoperative radiotherapy. Women were followed for an average of 5 years to determine the effectivity of intraoperative radiotherapy in preventing breast cancer recurrences and prolonging survival.

Overall, 35 patients (4.4%) in the intraoperative radiotherapy group and four patients (0.4%) in the external radiotherapy group experienced ipsilateral breast cancer recurrence (local recurrence in the same breast as the original tumor). However, both the rate of metastatic recurrence and overall survival were similar between treatment groups. The 5-year survival rate was 96.8% among women in the intraoperative radiotherapy group and 96.9% among women in the external radiotherapy group. In addition, significantly less skin related side-effects were noted in women undergoing intraoperative radiotherapy, with only 11 women experiencing any type of skin toxicity.

This study concluded that intraoperative single-dose radiotherapy provides a safe and effective treatment alternative to standard breast irradiation.

Despite a low rate of local breast cancer recurrence in the intraoperative radiotherapy group, the risk of local recurrence was significantly greater compared to external whole-breast radiotherapy.