Six-year experience: long-term disease control outcomes for partial breast irradiation using MammoSite balloon brachytherapy

BACKGROUND: This report describes estimated 4-year tumor bed and ipsilateral breast recurrence-free intervals, event-free survival, disease-specific survival, and overall survival in a cohort of MammoSite brachytherapy (MBT) patients with mature follow-up treated at a single institution over a 6-year period. METHODS AND MATERIALS: An analysis of MBT cases was performed by using a prospectively collected quality-assurance database, departmental chart review, and electronic medical records. Patient-, tumor-, treatment-, and outcome-specific data were extracted and recorded into a research database. Patients were eligible for inclusion in this analysis if they were at least 6 months post-MBT. RESULTS: From May 2002 through March 2008, 111 MBT patients have been treated and were eligible for the present analysis. With a median follow-up of 46 months, the estimated 4-year outcomes for the entire cohort were tumor bed control 99%, ipsilateral breast control 95%, event-free survival 88%, disease-specific survival 97%, and overall survival 92%. CONCLUSIONS: The present study shows low rates of local and ipsilateral breast disease failure in a well-defined cohort of MBT patients with mature follow-up.