Histologic grade, stage, and survival in breast carcinoma: comparison of African American and Caucasian women

Abstract

Background: African American women have lower breast carcinoma survival rates than do Caucasian women. African American women often present with advanced-stage disease and more aggressive tumors as shown by histologic and laboratory-based prognostic factors. Aggressive tumor behavior may be responsible, at least in part, for the advanced stage and reduced survival rates.

Methods: The authors investigated the correlation between survival and histologic grade, stage of disease, and tumor size for both African American and Caucasian women who were younger than age 50 years and age 50 years and older. The authors also investigated the distribution of grade within each stage group and the distribution of grade by tumor size. African American and Caucasian women were matched by stage, tumor size, and histologic grade. Survival was represented by 6-year breast carcinoma-specific survival rates.

Results: Compared with Caucasian women, African American women, regardless of age, had proportionally more Grade III tumors and fewer Grade I and II tumors for all stages combined and for each individual stage group. Similarly, matched for tumor size, African American women had more Grade III tumors and fewer Grade I and II tumors compared with Caucasian women, except for tumors smaller than 1.0 cm. For nearly all combinations of stage and grade regardless of age, the 6-year breast carcinoma-specific survival rate was lower for African American women than for Caucasian women, although it did not always reach statistical significance.

Conclusions: Compared with Caucasian women, African American women, regardless of age, presented with proportionally more aggressive tumors for each stage of disease and for each tumor size above 1.0 cm as revealed by the histologic grade. Higher histologic grade may be a significant contributing factor to survival disadvantage for African American women.