Basal cell–like (triple-negative) breast cancer, a predictor of distant metastasis in African American women

Background The aim of this study was to evaluate the prognostic significance of the basal cell–like molecular breast cancer subtype with respect to locoregional recurrence and distant metastasis in African American women treated for breast cancer. Methods A retrospective analysis was performed of the tumor registry database for all African American women diagnosed and treated for breast cancer from 1998 to 2005 who had assessable data for all 3 markers: estrogen, progesterone, and Her-2/neu. Results A total of 372 patients were included in our study sample. Of these, 22 (6.1%) had locoregional recurrence, 35 (9.8%) had distant metastasis, and 301 (84.1%) had no evidence of breast tumor recurrence. The median follow-up time was 36 months. Compared with the other molecular subtypes the basal cell–like subtype showed a statistically significant association to distant metastasis: 15 (42.9%) vs 13 (37.1%), 4 (11.4%), and 3 (8.6%) (P < .001), respectively, for luminal A, Her-2/neu, and luminal B subtypes. The basal cell–like subtype was an independent predictor of distant metastasis (odds ratio, 5.8; 95% confidence interval, 1.5–22.0, P = .009). The molecular subtypes showed no statistically significant difference with respect to locoregional treatment administered and tumor stage at time of diagnosis. Conclusions The basal cell–like molecular breast cancer subtype is an independent predictor of distant metastasis in African American women.