Impact of race and ethnicity on features and outcome of ductal carcinoma in situ of the breast.

BACKGROUND: The impact of race and ethnicity on the biologic features and outcome variables of women who are diagnosed with preinvasive breast cancer-ductal carcinoma in situ (DCIS)-has not been addressed widely in the published literature.
METHODS: Patient demographic, clinical, and pathologic features and outcome variables were analyzed with respect to the patient's initial self-reported race/ethnicity among women who received treatment for a diagnosis of pure DCIS from 1996 to 2009.
RESULTS: Of 1902 patients, 1411 were white (74.2%), 214 were African American (11.3%), 175 were Hispanic (9.1%), and 102 were Asian/Pacific Islander (5.4%). The majority of patients were between ages 41 and 70 years (83%). Patients of Hispanic and Asian/Pacific Islander descent were significantly younger than white and African American patients (P < .001). DCIS size and grade, the presence of necrosis, and the frequency of breast-conserving surgery did not differ significantly between groups. African American patients aged >70 years and Hispanic patients aged <50 years were significantly more likely to have estrogen receptor-positive DCIS than patients of other races in the same age categories (P < .001). Adjuvant radiotherapy and tamoxifen were received significantly less often by white women (P < .001). At a median follow-up of 4.8 years (range, 1-14 years), recurrence rates and the development of contralateral breast cancer did not differ significantly among racial/ethnic groups when stratified by treatments received.
CONCLUSIONS: There was variation in age at presentation, biologic features, and treatment of DCIS among the different ethnic groups. Additional studies with larger numbers of ethnic minority patients are needed to confirm whether the consistent application of evidence-based treatment practices presents an opportunity for reducing disparities in patients with DCIS.