Clinicopathological characteristics of triple-negative invasive mammary carcinomas in African-American versus Caucasian women.

ABSTRACT

African-American (AA) women are more likely to have late stage, aggressive, rapidly growing, and less hormone-responsive breast tumors. An aggressive subtype of cancer, known as "Triple-Negative" (TN), that is negative for Her-2 and for estrogen and progesterone receptors (ER and PR), is reported to be more common in AA women. We examined the clinical, histopathologic, and prognostic features of TN tumors in AA and Caucasian women. Tumor size, grade, histologic type, lymphovascular invasion (LVI), lymph node status, patient survival, ploidy status, and expression of ER, PR, p53, epidermal growth factor receptor (EGFR), MIB-1, Bcl-2, Her-2, p27, and p21 were evaluated. The TN tumors (75%) were high grade, large, aneuploid tumors that occurred in younger women and were more likely to have a high rate of LVI, elevated MIB-1 score, and nodal metastases. Patients with TN tumors showed poorer overall survival. There was no difference in overall or disease-free survival (p = 0.46) in the AA versus Caucasian women. LVI was a significant predictor of overall survival in AA but not in Caucasian women. There were minor differences in histopathologic features, biomarker expressions, and survival in AA and Caucasian women with TN tumors. The absence of LVI in AA patients predicted an excellent probability of survival.