A 12-Year Single-Institution Experience with Accelerated Partial Breast Irradiation

Area of Science:

• Oncology
• Radiotherapy
• Surgical Oncology

Background:

• The MammoSite® device for Accelerated Partial Breast Irradiation (APBI) gained FDA approval in 2002.
• Institutional adoption of APBI began in 2005, guided by the American Society of Breast Surgeons MammoSite® Breast Brachytherapy Registry.
• This study offers a 12-year institutional analysis of APBI patient outcomes.

Purpose of the Study:

• To analyze patient outcomes, including recurrence and complications, from 12 years of MammoSite® APBI use.
• To evaluate the long-term efficacy and safety of APBI in a single institution.
• To compare institutional APBI outcomes with national data.

Main Methods:

• Retrospective review of 150 patients undergoing APBI or attempted APBI after breast-conserving surgery (2006-2017).
• Analysis of patient age, cancer stage, recurrence incidence, and posttreatment complications.
• Assessment of treatment completion rates and time since treatment.

Main Results:

• 99% of patients completed APBI treatment, with a median follow-up of 8.9 years.
• Ipsilateral breast recurrence occurred in 2.7% of patients; new primary breast tumors in 1.3%.
• Acute complications (e.g., skin erythema) were uncommon and self-limited; subacute effects included fibrosis (13%) and mild pain (9.4%).

Conclusions:

• APBI using MammoSite® demonstrates good outcomes for select breast cancer patients post-breast-conserving surgery.
• Local control and toxicity profiles are consistent with published literature.
• Five-year local recurrence rates are favorable compared to national trials, with occasional complications like fibrosis and pain.