Original article / research
Year : 2026 Month : July Volume : 15 Issue : 3 Page : PO06 - PO11 Full Version

Immunohistochemical Evaluation of BRAF V600E and HER2 Expression in Colorectal Carcinoma and Their Association with Clinicopathological Parameters: A Cross-sectional Study from a Tertiary Care Centre in Eastern India
Nakka Vaishnavi, Rina Barman, Tarak Banik
1. Junior Resident, Department of Pathology, R G Kar Medical College, Kolkata, West Bengal, India. 2. Associate Professor, Department of Pathology, R G Kar Medical College, Kolkata, West Bengal, India. 3. Associate Professor, Department of Pathology, R G Kar Medical College, Kolkata, West Bengal, India.
 
Correspondence Address :
Rina Barman,
Department of Pathology, Kolkata, West Bengal, India.
E-mail: dr.rinabarman@gmail.com
 
ABSTRACT
: Introduction: Colorectal Carcinoma (CRC) is the third most common cancer in the world according to Global Cancer Observatory (GLOBOCAN) statistics, 2022. CRC’s phenotypic and molecular comprehensive characterisation represents a key step, with diagnostic and prognostic value assessment of BRAF V600E {B-Raf proto-oncogene, serine/threonine kinase (VAL600GLU)} and Human Epidermal Growth Factor Receptor 2 (HER2) expression using Immunohistochemistry (IHC) can aid in understanding tumour characteristics in routine diagnostic practice.

Aim: The aim of the present study was to evaluate the immunohistochemical expression of BRAF V600E and HER2 in CRC and their association with clinicopathological parameters.

Materials and Methods: The present observational cross-sectional study was conducted in the Department of Pathology, RG Kar Medical College and Hospital, Kolkata, West Bengal, India, over an 18-month period (July 2023 to December 2024) on 72 diagnosed cases of CRC. Clinicopathological parameters were recorded. IHC was performed using mutation specific monoclonal antibody for BRAF V600E (clone IHC600, GenomeMe, Canada) and HER2 clone EP3 Dygnova, India). Results were analysed using Statistical Package for the Social Sciences (SPSS) 27.0 (SPSS, Inc., Chicago, IL, USA) and carried out Chi-square and Fisher`s-exact tests, with p-value <0.05 was considered statistically significant.

Results: Out of 72 cases of CRC, BRAF V600E expression was positive in 16 cases (22.2%), equivocal in 7 cases (9.7%) and negative in 49 cases (68.1%). BRAF V600E positivity showed a statistically significant association with poor differentiation (p=0.027), advanced stage (p=0.0086), lymph node metastasis (p=0.0055), Lympho-Vascular Invasion (LVSI) (p=0.037) and mucinous histology (p=0.0001). HER2 expression was positive in three cases (4.17%), borderline in four cases (5.56%) and negative in 65 cases (90.27%). HER2 expression showed a significant association only with tumour grade (p=0.009).

Conclusion: BRAF V600E expression is significantly associated with aggressive clinicopathological features in CRC, while HER2 expression showed limited association. Immunohistochemistry serves as a useful screening tool for molecular alterations, however confirmatory molecular testing and long-term follow-up studies are required to establish prognostic significance.
Keywords : Adenocarcinoma, Human epidermal growth factor receptor 2, Pathological staging, Protein expression, Tumour grading
DOI and Others : DOI: 10.7860/NJLM/2026/85385.2975 Date of Submission: Nov 15, 2025 Date of Peer Review: Jan 07, 2026 Date of Acceptance: Mar 12, 2026 Date of Publishing: Jul 01, 2026 AUTHOR DECLARATION: • Financial or Other Competing Interests: None • Was Ethics Committee Approval obtained for this study? Yes • Was informed consent obtained from the subjects involved in the study? Yes • For any images presented appropriate consent has been obtained from the subjects. Yes PLAGIARISM CHECKING METHODS: • Plagiarism X-checker: Dec 15, 2025 • Manual Googling: Mar 05, 2026 • iThenticate Software: Mar 11, 2026 (1%) ETYMOLOGY: Author Origin EMENDATIONS: 7
 
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