Prognostic Implications of ER, PR and HER2/Neu Protein Expression in a Cohort of Breast Carcinoma

Abstract

ER, PR and HER 2/neu receptor studies are known to be prognostic and predictive biomarkers of breast carcinoma. Hence the status of ER, PR and HER 2/neu receptors are routinely assessed in breast carcinoma by immunohistochemistry using paraffin embedded tissue blocks. The reason for assessing the receptor status is to decide on the best treatment regime for breast cancer patients. Ki 67 which is a biomarker of cellular proliferation is also assessed to guide the oncologist by determining the proliferative capacity of the tumour. A descriptive cross-sectional study conducted during January 2016 to December 2018 in three specialized surgical centres. Study sample included 92 patients with histologically confirmed breast carcinoma. ER, PR, HER2/neu receptor status and Ki 67 proliferative index were assessed to determine the prognostic implications of breast carcinoma. Mean age at presentation was 53.99 years and the most common histological type was invasive ductal carcinoma (84.78%). In the cohort of 92 patients with breast carcinoma 73.91% were ER positive, 58.69% were PR positive, and 11.95% were HER2/neu positive. Lymph nodal involvement was seen in 31.52% of the patients. There was no statistically significant association with HER2/neu status and nodal involvement (p = 0.629). Distant metastasis was seen in 4.35% cases. The association with HER2/neu status and distant metastasis was not statistically significant (p = 0.085). ER status showed a significant negative correlation with HER2 status (rho = -0.634, p < 0.0001). PR status showed a significant negative correlation with HER2 status (rho = -0.834, p < 0.0001). Ki67 index showed a significant positive correlation with HER2 status (rho = 0.248, p = 0.017).