Molecular epidemiologic features of inflammatory breast cancer: a comparison between Egyptian and US patients.
BACKGROUND
Inflammatory breast cancer (IBC) is a lethal form of breast cancer with unknown etiology. A higher frequency of IBC and a more aggressive IBC phenotype was reported in Egypt than in the United States. This difference in disease frequency and presentation might be related to molecular epidemiologic factors.


METHODS
We used tumor blocks and demographic, epidemiologic, and clinical data of 48 IBC patients from Egypt and 12 patients from the United States. We counted tumor emboli in tumors before and after immunohistochemical staining with lymphatic vessel endothelial receptor-1 (LYVE-1), and measured the expression of RhoC GTPase protein in the two groups.


RESULTS
Erythema, edema, and peau d'orange were found in 77% of the Egyptian patients as compared with 29% found in the US patients (P=0.02). The number of tumor emboli was significantly higher in tumors from Egypt (mean+/-SD, 14.1+/-14.0) than in the tumors from the United States (5.0+/-4.0, P=0.01). The number of tumor emboli in LYVE-1 positive vessels was higher in tumors from Egypt (3.5+/-2.8) than tumors from the United States (1.6+/-0.5, P=0.15). We detected a high level of RhoC in 87% of the tumors from Egypt and 14% of the tumors from the United States (P=0.0003).


CONCLUSIONS
Patients from Egypt have a more aggressive form of IBC than those in the United States. Our analysis of IBC patients shows that distinct molecular phenotypes can be found when these two study populations are compared. Future studies should explore the epidemiologic and environmental exposures and the genetic factors that might lead to the different clinical and molecular features of IBC in patients from these two countries.
Lo
An-Chi
AC
Department of Epidemiology, University of Michigan School of Public Health, 109 Observatory Street, Ann Arbor, MI 48109, USA.
Kleer
Celina G
CG
Banerjee
Mousumi
M
Omar
Sherif
S
Khaled
Hussein
H
Eissa
Saad
S
Hablas
Ahmed
A
Douglas
Julie A
JA
Alford
Sharon H
SH
Merajver
Sofia D
SD
Soliman
Amr S
AS
D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000150:complications / Q000453:epidemiology* / Q000235:genetics*; D004534:Egypt / Q000453:epidemiology; D016021:Epidemiologic Studies; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D015994:Incidence; D007249:Inflammation; D008499:Medical Records; D008875:Middle Aged; D017720:Molecular Epidemiology; D011379:Prognosis; D046888:Tissue Array Analysis; D014481:United States / Q000453:epidemiology; D033921:Vesicular Transport Proteins / Q000235:genetics*; D020741:rho GTP-Binding Proteins / Q000235:genetics*; D000075024:rhoC GTP-Binding Protein
C119248:LYVE1 protein, human; D033921:Vesicular Transport Proteins; C066690:RHOC protein, human; D020741:rho GTP-Binding Proteins; D000075024:rhoC GTP-Binding Protein