Five-year analysis of treatment efficacy and cosmesis by the American Society of Breast Surgeons MammoSite Breast Brachytherapy Registry Trial in patients treated with accelerated partial breast irradiation.

Purpose: To present 5-year data on treatment efficacy, cosmetic results, and toxicities for patients enrolled on the American Society of Breast Surgeons MammoSite breast brachytherapy registry trial.

Methods And Materials: A total of 1440 patients (1449 cases) with early-stage breast cancer receiving breast-conserving therapy were treated with the MammoSite device to deliver accelerated partial-breast irradiation (APBI) (34 Gy in 3.4-Gy fractions).

Five-year results: the initial clinical trial of MammoSite balloon brachytherapy for partial breast irradiation in early-stage breast cancer.

Objective: Patients with early-stage invasive ductal breast cancer were prospectively evaluated using MammoSite RTS balloon brachytherapy (RTS Cytyc Corp, Marlborough, MA) as the sole modality for delivering accelerated partial breast irradiation to the lumpectomy bed with breast-conserving surgery. This report presents the 5-year results of the treated patients.

Methods: From May 2000 to October 2001, 70 patients were enrolled in this prospective study.