Immunohistochemical Expression of ER, PR, and HER2/Neu in Breast Carcinoma -A Cross Sectional Study

Abstract

BACKGROUND
Breast carcinoma is a heterogeneous disease characterized by distinct molecular subtypes that influence treatment strategies and patient outcomes. This study explores the significance of immunohistochemical (IHC) profiling in breast carcinoma, focusing on key biomarkers:
estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor
receptor 2 (HER2/Neu).
OBJECTIVE
To find the correlation of ER, PR and Her2/neu IHC markers with clinical features, tumour size, lymph node involvement and histopathological grade.
METHODS
A three year prospective observational cross sectional study was conducted in the Department
of Pathology, in integration with Department of General Surgery and Radiotherapy at Rangaraya Medical College, Kakinada, Andhra Pradesh, India. A total of 55 cases of breast
carcinoma were included in the study. The histopathological grading of the breast carcinoma
was done according to the Nottingham modification of the Bloom Richardson grading system.
All the cases underwent immunohistochemistry for ER, PR and Her2neu expression. Correlation of ER, PR and Her2neu with various prognostic factors was done.
RESULTS
The study included a total of 55 cases, out of which 22/55 (40%) were below 40yrs and 33/55
(60%) were above 40yrs. 60% of the tumors were in the size range of 2-5 cm (T2). 34.5% of
the tumors belong to N2 category and 58.2% of the tumors were of high grade. 43.6% of the
patients fall under Stage IIIA group. 78.2%) were of Invasive Ductal Carcinoma of No Special
Type (NST). About 51% of the patients were ER/PR negative. Half of the patients (51%) were
Her2/neu negative (Grade I (0/1+)), 25.5% were Her2/neu positive (Grade III) and 23,6 % were
unequivocal. CONCLUSION
Our study contributes to the body of evidence regarding histological grading and receptor
expression in breast cancer within Asian populations. The observed lower rates of ER and PR
positivity, alongside the relatively high prevalence of Grade III tumors, highlight the need for
ongoing research to understand the factors influencing these trends and to optimize treatment strategies tailored to specific patient demographics.