Epidermal Growth Factor Receptor Expression in Triple Negative and Nontriple Negative Breast Carcinomas

The panel of markers used for molecular classification include estrogen receptors (ER), progesterone receptors (PR), human epidermal growth factor receptor (HER)-2/neu, p53, Bcl-2 and basal markers like cytokeratin 5/6 or epidermal growth factor receptor (EGFR). Among these, EGFR plays an important role and is associated with bad prognosis.

To study EGFR expression in triple negative breast carcinoma (TNBC) and non-TNBCs (NTNBCs).

Fifty cases of breast carcinomas were classified and graded according to World Health Organization and Nottingham modification of Scarff-Bloom-Richardson (SBR) system, respectively. The age of the patients ranged from 28 to 69 years. Histological features such as necrosis, pushing borders, lymphocytic infiltrate and periductal elastosis were noted. The panel of markers used in our study included ER, PR, HER-2/neu and EGFR. EGFR expression was assessed based on membrane staining. Chi-square test was applied for statistical analysis to compare EGFR expression with hormonal status and prognostic factors. P < 0.05 was considered significant.

The mean age was 49.8 ± 7.2 years. There were 44 (88%) infiltrating ductal carcinoma, 3 (6%) medullary carcinoma and 3 (6%) mucinous carcinoma. EGFR expression was common in young patients and was predominant in TNBC (89.47%), was also expressed in few cases of NTNBC. There was a positive correlation of EGFR expression (P = 0.03491) with a high grade. Medullary carcinomas were triple negative and strongly expressed EGFR. EGFR expression was inversely associated with ER status and showed strong association with necrosis and lymphocytic infiltrate, but not with pushing border and periductal elastosis.

EGFR is an important marker to stratify patients with breast cancer according to molecular classification. Its expression correlated positively with young age, higher SBR grade, necrosis, lymphocytic infiltrate and inversely with hormonal receptor expression.