Abstract :
Introduction: Colorectal malignancies stand out to be one of the chief causes of morbidity and mortality
in the world. Although the total incidence of colorectal malignancy in India n population has marginally
increased, it is now a common cause of cancer mortality among Indians.
The oncogene HER2/neu belongs to the tyrosine kinase receptor family. The favorable outcome of
HER2/neu in management of breast carcinoma patients has direct ed to evaluation of gene amplification
protein overexpression, and anti-tumor activity of Herceptin in various tumor types one amongst which
is colorectal carcinomas. The objective of the study was to evaluate the frequency of overexpression of
HER2/neu in colorectal adenocarcinomas (CRC) and its association with various histomorphological and
clinicopathological parameters.
Materials and Methods: A total of 52 cases of colorectal adenocarcinomas including colonoscopic
biopsies & resected specimens were studied. Paraffin embedded sections were stained with Hematoxylin &
Eosin and histological and clinicopathological parameters were assessed. In IHC, antigens were retrieved
by Heat Induced Epitope Retrieval method and HER2/ neu status was determined using a semiquantitative
scoring system. The scores were then correlated with histological grade, type and clinicopathological
parameters.
Results: The HER2/neu overexpression was noted in 53.8% of our cases and was seen to be commonly
expressed by moderately differentiated tumours and conventional/ NOS histological type.
There was a statistically significant correlation observed between HER2/neu status and tumour grade (p=
0.001), tumour type (p = 0.008). There was no significant correlation between age, gender or localisation
or stage of tumour.
Conclusion: Histological grade and histological type of CRC showed a significant correlation with
HER2/neu overexpression, hence can be used as a predictive tool for determining the prognosis of the
patients.
Patients who overexpress HER2/neu could become potential candidates for this monoclonal antibody based
targeted immunotherapy thus reduce overall mortality and morbidity of CRC worldwide.
Keyword :
HER2/neu, Colorectal adenocarcinoma.