Status of HER-2/neu receptors and Ki-67 in breast cancer of Indian women.

Background: Breast cancer is a leading cause of death in women. Receptor status is the most important prognostic and predictive marker for breast cancer.

Aims: The present study was conducted with an aim to analyze breast cancer of Indian women with discordant receptor status, probably hormone dependent estrogen receptor (ER) positive, progesterone receptor (PgR) negative or ER- negative and PgR+ positive subgroup profile, infiltrating ductal breast cancer (IDC) not otherwise specified.

Materials And Methods: Specimens from 100 IDC were grouped into three categories according to hormonal status (group 1: ER+ positive and PgR+ positive, group 2: ER+ positive and PgR- negative or ER- negative and PgR+ positive, group 3: ER- negative and PgR- negative) evaluated prognostic parameters.

Statistical Analysis: Statistically significant difference was found between tumor receptor status distribution and menopausal status (P = 0.0235), age of patients (P < 0.001), histopathologic grade (P < 0.001), vascular invasion (P = 0.006), HER-2/neu status (P = 0.004) and Ki-67 proliferation rate (P < 0.001).

Results: Group 1 tumors were found exclusively in post-menopausal patients with average age 68.9 years, most of which had intermediate grade II, without vascular invasion, with HER-2/neu status score predominantly 0 or 1+ and lower Ki-67 proliferation rate. Group 2 tumors were found predominantly in younger post-menopausal patients with average age 57.5 years, with vascular invasion found in 23% of cases. Group 3 tumors mostly had higher histopathologic grade, showed the highest percentage of the Ki-67 positive tumor cells and vascular invasion in 30% of the cases.

Conclusion: It is concluded that patients with group 2 breast cancer were younger post-menopausal women, with tumors moderately differentiated, HER-2/neu score 0 or 1+ and with lower Ki-67 proliferation rate.