Receipt of locoregional therapy among young women with breast cancer.
1100 Background: Although younger women with breast cancer have the most to gain from receipt of optimal care, few data are available regarding their receipt of locoregional breast cancer treatments. Methods: We identified 318,083 women aged 18-64 who were diagnosed with invasive breast cancer at hospitals reporting to the National Cancer Data Base, a large national cancer registry, during 2004-2008. We used multivariable logistic regression to assess the association of patient age with mastectomy vs. breast-conserving surgery (BCS), radiation with BCS, and post-mastectomy radiation (PMRT) with varying indications, adjusting for patient and tumor characteristics, area-level socioeconomic status, and insurance. Results: Overall, 4% of women were aged ≤35 and 7% were aged 36-40. Women aged ≤35 were significantly more likely to have mastectomy than BCS compared with women aged 56-60 (57% vs. 35%, adjusted odds ratio [OR] 1.97; 95% Confidence Interval [CI] 1.87-2.07) but were less likely to receive radiation if BCS was performed (69% vs. 80%, OR 0.77; 95% CI 0.73-0.82). For those who underwent mastectomy, although overall rates of PMRT receipt were low, women aged ≤35 were more likely to receive postmastectomy radiation (PMRT) despite the presence or absence of clinical indications for PMRT (OR 1.11; 95% CI 1.01-1.22 for strong indications, OR 1.71; 95% CI 1.53-1.91 for borderline indications, and OR 1.49; 95% CI 1.28-1.73 for no indications [all vs. ages 56-60]). Conclusions: Young women with breast cancer may not be receiving optimal locoregional therapy. We observed lower odds of radiation after BCS but higher odds of PMRT for young women regardless of indications for PMRT. Efforts are needed to further understand and improve the receipt of appropriate adjuvant radiation therapy among young women to improve their disease-free and overall survival.