Prognostic significance of overexpression and phosphorylation of epidermal growth factor receptor (EGFR) and the presence of truncated EGFRvIII in locoregionally advanced breast cancer.
OBJECTIVE
The prognostic value of the epidermal growth factor receptor (EGFR) in breast cancer and more specifically, in patients with locoregionally advanced disease, is still undefined. We hypothesized that EGFR status plays a major prognostic role in this setting, through expression, activation, or the presence of its mutated variant EGFRvIII.


METHODS
We reviewed tumor samples of 225 patients treated uniformly in prospective trials of high-dose chemotherapy for four to nine positive axillary nodes, > or = 10 positive nodes, or inflammatory carcinoma, and observed for a median of 9 years (range, 3 to 13 years). We analyzed the effect on outcome of expression of EGFR, phosphorylated EGFR (phospho-EGFR), and EGFRvIII, as studied by immunohistochemistry.


RESULTS
EGFR expression, phospho-EGFR, and mutated EGFRvIII were detected in 43%, 54%, and 4% of the patients, respectively. EGFR expression correlated with negative hormone receptor status, and was associated with significantly worse relapse-free survival (59% v 79%; P < .001) and overall survival (61% v 81%; P = .001) than no expression. There was no association of phospho-EGFR or EGFRvIII with outcome. Multivariate models confirmed the prognostic effect of EGFR independent of other known prognostic variables in this population. The prognostic value of EGFR was most prominent in the human epidermal growth factor receptor 2 (HER-2) -positive and the estrogen receptor/progesterone receptor-negative subgroups.


CONCLUSIONS
EGFR expression, but not phospho-EGFR or EGFRvIII expression, is an independent adverse prognostic factor in patients with high-risk primary breast cancer, particularly when it is coexpressed with HER-2. Our results suggest the potential benefit of dual EGFR/HER-2 receptor targeting in this setting.
Nieto
Yago
Y
Department of Stem Cell Transplantation and Cellular Therapy, Unit 423, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA. ynieto@mdanderson.org
Nawaz
Fatima
F
Jones
Roy B
RB
Shpall
Elizabeth J
EJ
Nawaz
Samia
S
D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology*; D066246:ErbB Receptors / Q000378:metabolism*; D005260:Female; D006801:Humans; D008875:Middle Aged; D015999:Multivariate Analysis; D010766:Phosphorylation; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D016019:Survival Analysis
D014408:Biomarkers, Tumor; C410723:epidermal growth factor receptor VIII; D066246:ErbB Receptors