Introduction: EGFR over expression and mutation play an important role in the carcinogenesis of lung adenocarcinoma. The most common adenocarcinoma-associated EGFR mutations are in-frame deletions in exon 19 (E746_A750del) and the point mutation replacing leucine with arginine at codon 858 in exon 21 (L858R). Antibodies that specifically detect mutant EGFR protein by immunohistochemistry can be used to detect these specific mutations.

Objectives: 1) To find out the prevalence of EGFR mutations in lung adenocarcinoma patients using mutant specific immunohistochemical markers.

2) To assess the clinical and biological features associated with EGFR mutation.

Materials and Methods

Study Design: Descriptive Study

Study Population: All cases of Adenocarcinoma Lung diagnosed in the Department Of Pathology, Govt. Medical College, Kozhikode during the study period

Sample Size:100

Results: Of the 100 cases, 88 were male (88%) and 12 were female (12%) with a mean age of 63 years. Out of 100 cases, 19 cases showed EGFR mutation. 14 patients (13 males; 1 female) showed positivity for del E746-A750 and 9 patients for L858R (9 male, 0 female). 4 patients showed positivity for both. EGFR mutation rate was higher in adenocarcinomas of lepidic and acinar subtypes than of other subtypes(p< 0.05)

Conclusions: In this preliminary study, mutation specific IHC was used for assessment of mutation status of EGFR.IHC methodology is a potentially useful tool to guide clinicians for targeted therapies where facilities for molecular analysis are not readily available .

Keywords: Adenocarcinoma, Epidermal growth factor receptor (EGFR), exon 19, exon 21, mutation specific antibodies for E746-A750 and L858R.

1. Ferlay J, Soerjomatram I, Evik M, Dikshit R, Eser S, Mathers C et al. GLOBACON 2012 vl.0, Cancer Incidence and Mortality Worldwide: IARC Cancer Base No.11.Inernational Agency for Research on Cancer,Lyon,2014
2. Lynch TJ, Bell DW, Sordella R, et al. Activating mutations in the epidermal growth factor receptor underlying responsiveness of non-small-cell lung cancer to gefitinib. N Engl J Med 2004; 350:2129-39.
3. Shigematsu H, Lin L, Takahashi T, et al. Clinical and biological features associated with epidermal growth factor receptor gene mutations in lung cancers. J Natl Cancer Inst 2005;97:339–346.
4. Kim HR, Shim HS, Chung JH, et al. Distinct clinical features and outcomes in never-smokers with nonsmall cell lung cancer who harbor EGFR or KRAS mutations or ALK rearrangement. Cancer 2012; 118:729-39.
5. Antonicelli A, Cafarotti S, Indini A, et al. EGFR-targeted therapy for non-small cell lung cancer: focus on EGFR oncogenic mutation. Int J Med Sci 2013; 10:320-30.
6. Cadranel J, Ruppert AM, Beau-Faller M, et al. Therapeutic strategy for advanced EGFR mutant non-small-cell lung carcinoma. Crit Rev Oncol Hematol 2013;88:477-93
7. Gaur P, Bhattacharya S, Surya Kant, Kushwaha RAS, Agarwal J and Pathak AK. Epidermal Growth Factor Receptor Mutations Detection by Mutant Specific Immunohistochemistry in North Indian Lung Cancer population. J. Res. Dev. Pharm. L. Sci. 2017; 6(6): 2796-2799.
8. Deepali Jain,Sobuhi Iqbal et al. Evaluation of epidermal growth factor receptor mutations based on mutation specific immunohistochemistry in non-small cell lung cancer: A preliminary study Indian J Med Res. 2016 Mar; 143(3): 308–314
9. Dinesh C, Saud Azam, Ullas Batra et al. Epidermal growth factor receptor mutation in lung adenocarcinoma in India: A single centre study.journal of carcinogenesis.  2013; 12: 12
10. Choughule A, Noronha V, Joshi A, Desai S, Jambhekar N, Utture S, et al. Epidermal growth factor receptor mutation subtypes and geographical distribution amongIndian non-small cell lung cancer patients. Indian J Cancer. 2013; 50:107–11.
11. Zhen Chen, Xiaoyan Liu, Jing Zhao, Y Hanjin, T Xiaodong. Correlation of EGFR mutation and histological subtype according to the IASLC/ATS/ERS classification of lung adenocarcinoma. Int J Clin Exp Pathol.2014:7(11):8039-8045.

Dr Aswathy Shibu

Junior Resident, Department of Pathology, Govt. Medical College, Kozhikode, Kerala, India