6040 Background: The use of accelerated partial breast irradiation using brachytherapy (APBI-b) for patients with invasive cancer is increasing but data for ductal carcinoma in situ (DCIS) cases are limited. The American Society of Radiation Oncology (ASTRO) guidelines suggest that APBI-b should be used only on a "cautionary" or "on trial" basis for women with DCIS. The purpose of this study was to examine utilization trends and correlates of APBI-b use for patients with DCIS. Methods: A total of 70,043 postlumpectomy patients from the National Cancer Database diagnosed with DCIS between 2002 and 2007 were studied. Chi-square tests and logistic regression models were used to determine trends and factors related to APBI-b use. Results: The use of APBI-b increased from 0.7% in 2002 to 10.0% in 2007 (p<0.001). Independent predictors APBI-b use were age, race, insurance status, comorbidity index, facility type, and facility location. Older patients were more likely to use APBI-b; relative to patients 30-39 years old, the OR for patients 80-89 years old was 5.9 (95% CI: 3.7-9.6). APBI-b use was higher in whites (4.9%), compared to blacks (4.4%), Hispanics (2.8%), and Asian pacific islanders (1.5%; p<0.001). Compared to noninsured, Medicare (OR=2.1, 95% CI: 1.3-3.3) and managed care patients (OR=2.0, 95% CI: 1.3-3.2) were more likely to undergo APBI-b. 2.3% of community cancer programs, 5.7% of comprehensive community programs and 4.1% of academic/research programs utilized APBI-b for treating DCIS (p<0.001). The use of APBI-b varied significantly by facility location; the West and South regions of the country were more likely to use APBI-b (OR=14, 95% CI: 10.1-19.6) than the Northeast region. 91% of the APBI-b patients fit the ASTRO "cautionary" guideline and 9% of patients fit the ASTRO "on trial" guidelines. In 2002, 4% of ABPI-b patients fit the "on trial" guidelines which increased to 8.6% in 2007 (p<0.001). Conclusions: The use of APBI-b for DCIS increased from 2002-2007. APBI-b use varies by socioeconomic and facility factors with age being the most significant factor. Future studies are needed to determine the indications for APBI-b in patients with DCIS.
