Radiographic Findings after Treatment with Balloon Brachytherapy Accelerated Partial Breast Irradiation

The use of accelerated partial breast irradiation (APBI) following breast-conserving surgery is rapidly gaining popularity as an alternative to whole-breast irradiation (WBI) in selected patients with early-stage breast cancer. Although data on the long-term effectiveness and safety of APBI are still being gathered, the shorter treatment course and narrowed radiation target of APBI provide an attractive alternative for carefully selected patients. These patients include those with relatively small tumors (<= 3 cm), negative or close margins, and negative sentinel lymph nodes. Possible long-term complications include telangiectasia and the development of a palpable mass at the lumpectomy site. Mammographic findings in patients who have undergone APBI are distinct from those in patients who have undergone conventional WBI. The most common post-APBI radiographic findings include formation of seromas at the lumpectomy site, focal parenchymal changes such as increased trabeculation and parenchymal distortion, fat necrosis, and skin changes such as thickening or retraction. Given the continued evolution of breast cancer treatment, it is important that radiologists have a comprehensive understanding of APBI in terms of rationale, patient selection criteria, common postprocedural radiographic findings (and how they differ from post-WBI findings), and advantages and potential complications. (C) RSNA, 2015