Molecular breast cancer subtypes in premenopausal African-American women, tumor biologic factors and clinical outcome.
BACKGROUND
Breast cancer is currently viewed as a heterogeneous disease made up of various subtypes, with distinct differences in prognosis. Our goal was to study the distribution and to characterize the clinical and biological factors that influence the behavior and clinical management of the different molecular breast cancer subtypes in premenopausal African-American women.


METHODS
A retrospective analysis of Howard University Hospital tumor registry, for all premenopausal African-American women aged less than 50 years, diagnosed with breast cancer from 1998-2005, was performed.


RESULTS
The luminal A subtype was the most prevalent (50.0%), vs basal-cell-like (23.2%), luminal B (14.1%), and HER-2/neu (12.7%). However when stratified by age groups, results showed that in the age group <35 years the basal-cell-like subtype was the most prevalent (55.6%), vs 25.9%, 14.8%, and 5.6% for luminal A, luminal B, and HER-2/neu subtypes, respectively (P < .000). P53 mutation was more prevalent in the basal-cell-like subtype compared to luminal A (48.0% vs 18.6%, P < .01). The expression of the Bcl-2 gene differed by subtype, with the luminal A and luminal B subtypes more likely to overexpress the Bcl-2 gene (89.1% luminal A, 80.0% luminal B vs 47.6% basal-cell-like and 40.0% HER-2/neu, P < .000). Though not statistically significant, HER-2/neu and basal-cell-like subtypes had the shortest survival time (P < .31).


CONCLUSIONS
The high prevalence of the basal-cell-like subtype in young premenopausal African-American women aged <35 years may contribute to the poorer prognosis observed in this cohort of African-American women.
Ihemelandu
Chukwuemeka U
CU
Department of Surgery, Howard University Hospital, 2041 Georgia Avenue, N.W., Washington, D.C 20060, USA. emeka_ihemelandu@hotmail.com
Leffall
Lasalle D
LD
Dewitty
Robert L
RL
Naab
Tammey J
TJ
Mezghebe
Haile M
HM
Makambi
Kepher H
KH
Adams-Campbell
Lucile
L
Frederick
Wayne A
WA
D000328:Adult; D001741:Black or African American / Q000235:genetics*; D014408:Biomarkers, Tumor / Q000235:genetics*; D001943:Breast Neoplasms / Q000208:ethnology / Q000235:genetics* / Q000401:mortality / Q000601:surgery; D002280:Basal Cell Carcinoma / Q000208:ethnology / Q000235:genetics; D004252:DNA Mutational Analysis; D018572:Disease-Free Survival; D004219:District of Columbia; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology; D019254:Genes, bcl-2 / Q000235:genetics; D018734:Genes, erbB-2 / Q000235:genetics; D016158:Genes, p53 / Q000235:genetics; D006785:Hospitals, University; D006801:Humans; D008875:Middle Aged; D009376:Neoplasms, Hormone-Dependent / Q000208:ethnology / Q000235:genetics / Q000401:mortality; D020411:Oligonucleotide Array Sequence Analysis; D017697:Premenopause; D011379:Prognosis; D011960:Receptors, Estrogen / Q000235:genetics; D011980:Receptors, Progesterone / Q000235:genetics; D012042:Registries; D012189:Retrospective Studies; D018426:SEER Program
D014408:Biomarkers, Tumor; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone