Accelerated Partial-Breast Irradiation Versus Whole-Breast Irradiation for Early-Stage Breast Cancer Patients Undergoing Breast Conservation, 2003–2010: A Report from the National Cancer Data Base

Previous studies have demonstrated an increase in the utilization of accelerated partial-breast irradiation via brachytherapy (APBI-b), but larger, more contemporary studies examining overall APBI use are lacking.

A total of 575,438 nonneoadjuvant American Joint Committee on Cancer stage 0 to II breast conservation patients were selected from the National Cancer Data Base from 2003 to 2010 who underwent either whole-breast irradiation or APBI.

Overall, 59,396 patients (10.3 %) underwent APBI. The use of APBI for the entire cohort increased from 3.4 % in 2003 to 12.8 % (p < 0.001) in 2008 and then decreased to 12.4 % in 2010. Three-dimensional conformal radiation increased from 0.8 to 2.2 %, intensity-modulated radiotherapy increased from 0.7 to 1.3 %, and brachytherapy (APBI-b) increased from 2.0 to 8.9 %. The most significant factors associated with APBI use were patient age and facility location. Patients 80–89 years old were 3.8 times more likely to undergo APBI compared to patients 30–39 years old (odds ratio [OR] 3.77, 95 % confidence interval [CI] 3.45–4.10, p < 0.001). Patients living in the West census region were 2.0 times more likely to undergo APBI compared to patients living in the Northeast (OR 2.0, 95 % CI 1.93–2.15, p < 0.001). Using the American Society of Radiation Oncology (ASTRO) guidelines, among patients with noninvasive cancer who received APBI, 95.6 % were categorized as “cautionary” and 4.4 % as “unsuitable.” Of the invasive patients, 43.8 % were categorized as “suitable,” 47.0 % as “cautionary,” and 9.2 % as “unsuitable.”

The utilization of APBI has stabilized at approximately 12 % starting in 2008. The majority of APBI is delivered using APBI-b, with patient age being the most significant factor associated with APBI use.