Correlation of HER-2/neu protein overexpression with other prognostic and predictive factors in invasive ductal breast cancer.

Background: The objective of our study was to investigate the association between Her-2/neu status and other clinicopathological characteristics of ductal breast carcinoma.

Patients And Methods: A total of 120 cases of breast carcinoma were included in this study. The immunohistochemical staining for HER-2/neu, hormone receptors, p53 and Ki-67 were evaluated.

Results: HER-2/neu protein overexpression was present in 4 out of 63 T1 lesions, in 13 out of 44 T2 lesions, in 3 out of 7 T3 lesions, and in 3 out of 6 T4 lesions. Protein overexpression was found in 10 out of 21 grade III tumors and 13 out of 72 grade II tumors. Overexpression was not detected in grade I tumors. Of the 23 Her-2/Neu-positive cases, ER- and PR-negative status was detected in 61% and 69%, respectively. Her-2 protein overexpression was seen in 23 out of 93 high Ki-67 tumors, whereas overexpression was not detected in low Ki-67 cases.

Conclusion: Statistically significant correlation was found between HER-2/neu protein overexpression and large tumour size, high histological grade, ER and PR negativity, and high Ki-67 proliferative index.