Characterization of Recurrences Following Second Breast-Conserving Surgery with Intraoperative Radiotherapy.

Background: Breast-conserving surgery with breast re-irradiation is an emerging technique in the treatment of selected cases of locally recurrent breast cancer. Further information is needed to characterize factors that may select for an appropriate patient population for this treatment approach.

Methods: We report herein a single-institution retrospective analysis of patients with ipsilateral breast cancer recurrence treated with a second breast-conserving therapy with intraoperative radiotherapy. Patient records were reviewed to analyze toxicity, further recurrence, and characteristics of recurrent patients following this treatment approach.

Results: We included 57 patients in the analysis. At median follow-up of 24.5 months, ipsilateral breast tumor recurrence occurred in six patients (11%), four of which localized to the quadrant of the initial recurrent disease and two of which recurred elsewhere in the treated breast. Locoregional control was 89%, and disease-free survival was 81%. Only one patient was found to have grade 3 or greater toxicity.

Conclusion: A second breast-conserving surgery with intraoperative radiotherapy is tolerable with acceptable toxicity for patients with locally recurrent disease refusing mastectomy. Prospective clinical trials are needed to define the subset of patients who may be appropriate for this treatment approach as an alternative to mastectomy.