Use of neoadjuvant chemotherapy for patients with stage I to III breast cancer in the United States

Background: Neoadjuvant chemotherapy (NAC) is the standard of care for patients with locally advanced breast cancer and can yield clinical advantages in individuals with lower stage cancers as well. To the authors' knowledge, the extent and patterns of use of NAC remain unknown. The objective of the current study was to assess temporal trends in NAC use and to examine what clinical, demographic, and treatment site characteristics influence its use.

Methods: Data from the National Cancer Data Base regarding 395,486 patients with stage I to stage III breast cancer who received adjuvant or neoadjuvant chemotherapy in the United States from 2003 through 2011 were analyzed. Chi-square tests and logistic regression analyses were used to assess the association between NAC use and patient, tumor, and facility characteristics.

Results: Overall, 17.4% of patients received NAC, including 4% of patients with stage I disease, 17.8% of patients with stage II disease, and 41.6% of patients with stage III disease. NAC use increased over time from 12.2% to 24.0%, particularly among patients with more advanced cancers. Rates increased from 12.9% to 39.3% in patients with stage IIIA, from 72.3% to 86.4% in patients with stage IIIB, and from 30.1% to 59.3% in patients with stage IIIC cancers. On multivariate analysis, patients aged <60 years, African American individuals, and those treated in academic centers were more likely to receive NAC. NAC use also varied by geographic region and was the highest in the West South Central region (21%) and lowest in the Midwest (15.2%).

Conclusions: Although NAC use increased between 2003 and 2011, <50% of all patients with stage III breast cancer were treated with NAC. Substantial regional and practice-related variations exist.