Differences in breast carcinoma characteristics in newly diagnosed African-American and Caucasian patients: a single-institution compilation compared with the National Cancer Institute's Surveillance, Epidemiology, and End Results database.
BACKGROUND
Breast carcinomas in African-American patients appear to be more aggressive than in Caucasian patients due to multifactorial differences.


METHODS
The authors compiled pathology data from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database regarding stage, histologic grade, and estrogen receptor (ER) expression in breast carcinomas diagnosed in 197,274 African-American and Caucasian patients between 1990 and 2000, and the same information, along with nuclear grade, Ki-67, c-erb-B2, and p53 expression, in 2230 African-American and Caucasian patients diagnosed at Thomas Jefferson University Hospital between 1995 and 2002. Immunohistochemical markers were assayed in paraffin-embedded, formalin-fixed tissue stained with hematoxylin and eosin using antibodies to these proteins, with differences in expression analyzed by the chisquare test.


RESULTS
In both databases, more African-American patients presented with advanced stage tumors and higher histologic (P < .001) and nuclear grade (P < .001) than Caucasian patients. African-American patients had less ER positivity (51.9% vs 63.1%; P < .001) but significantly higher Ki-67 (42.4% vs 28.7%; P < .001) and p53 expression (19.4% vs 13.1%; P < .05) than Caucasian patients with all stages of disease. In addition, the basal or "triple-negative" breast cancer phenotype was more common in African-American patients than in Caucasian patients (20.8% vs 10.4%; P < .0001), and was associated with higher histologic and nuclear grade (P < .0001).


CONCLUSIONS
African-American patients with breast carcinomas are more likely than Caucasian patients to present with tumors that are of a later stage and higher grade, with higher Ki-67 expression and more ER negativity, thereby highlighting a greater need for early screening among African-American women. Molecular studies that may explain these differences, and correlations with survival, have been proposed to identify therapeutic targets.
Morris
Gloria J
GJ
Department of Medical Oncology, Kimmel Cancer Center, Thomas Jefferson University Hospital, Philadelphia, PA 19107, USA. gloria.morris@jefferson.edu
Naidu
Sashi
S
Topham
Allan K
AK
Guiles
Fran
F
Xu
Yihuan
Y
McCue
Peter
P
Schwartz
Gordon F
GF
Park
Pauline K
PK
Rosenberg
Anne L
AL
Brill
Kristin
K
Mitchell
Edith P
EP
D001741:Black or African American / Q000706:statistics & numerical data*; D001943:Breast Neoplasms / Q000175:diagnosis / Q000208:ethnology* / Q000378:metabolism; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D019394:Ki-67 Antigen / Q000032:analysis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis; D012042:Registries / Q000706:statistics & numerical data; D016159:Tumor Suppressor Protein p53 / Q000032:analysis; D014481:United States / Q000453:epidemiology; D044465:White People / Q000706:statistics & numerical data*
D019394:Ki-67 Antigen; D018719:Erb-b2 Receptor Tyrosine Kinases; D016159:Tumor Suppressor Protein p53