title: Evaluation of epidermal growth factor receptor mutations based on mutation specific immunohistochemistry in non-small cell lung cancer: A preliminary study.
abstract: OBJECTIVE
  Studies have shown that immunohistochemical (IHC) staining using epidermal growth factor receptor (EGFR) mutation specific antibodies, is an easy and cost-effective, screening method compared with molecular techniques. The purpose of present study was to assess the percentage positivity of IHC using EGFR mutation specific antibodies in lung biopsy samples from patients with primary lung adenocarcinoma (ADC).
  
  
  METHODS
  Two hundred and six biopsies of primary lung ADC were subjected to EGFR mutation specific antibodies against del E746-A750 and L858R. Detection of EGFR mutation done by high resolution melting analysis (HRM) was used as gold standard. A concordance was established between molecular and IHC results. Frequency of IHC positivity was assessed.
  
  
  RESULTS
  Of the 206 patients, 129 were male and 77 were female patients, with a mean age of 54.1 yr. Fifty five (26.6%) patients (36 men; 19 women) showed positivity for IHC of del E746-A750 (33) and L858R (22). HRM results were available in 14 patients which showed EGFR mutations in correspondence with del E746-750 or L858R in 64.2 per cent cases. Positive cases on HRM were further confirmed by DNA sequencing and fragment analysis. Three patients showed exon[20] variation. Two cases were negative for mutation. The genotype of del E746-750 mutation was more common than L858R. A concordance was established between molecular mutation and IHC in 85.7 per cent cases.
  
  
  CONCLUSIONS
  In this preliminary study from India mutation specific IHC was used for assessment of mutation status of EGFR. Although the number tested was small, a good concordance was observed between molecular EGFR mutation and IHC expression. IHC methodology is a potentially useful tool to guide clinicians for personalized treatment in lung ADC, especially where facilities for molecular analysis are not readily available and for use in small biopsies where material is scant for molecular tests.
authors.affiliation: Department of Pathology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Deepali
authors.initials: D
authors.lastname: Jain
authors.affiliation: Department of Medical Oncology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Sobuhi
authors.initials: S
authors.lastname: Iqbal
authors.affiliation: Department of Pathology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Ritika
authors.initials: R
authors.lastname: Walia
authors.affiliation: Department of Medical Oncology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Prabhat
authors.initials: P
authors.lastname: Malik
authors.affiliation: Department of Medical Oncology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Sunu
authors.initials: S
authors.lastname: Cyriac
authors.affiliation: Department of Pathology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Sandeep R
authors.initials: SR
authors.lastname: Mathur
authors.affiliation: Department of Pathology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Mehar C
authors.initials: MC
authors.lastname: Sharma
authors.affiliation: Department of Pulmonary Medicine, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Karan
authors.initials: K
authors.lastname: Madan
authors.affiliation: Department of Pulmonary Medicine, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Anant
authors.initials: A
authors.lastname: Mohan
authors.affiliation: Department of Radiodiagnosis, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Ashu
authors.initials: A
authors.lastname: Bhalla
authors.affiliation: Department of Radiation Oncology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Sushmita
authors.initials: S
authors.lastname: Pathy
authors.affiliation: Department of Medical Oncology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Lalit
authors.initials: L
authors.lastname: Kumar
authors.affiliation: Department of Pulmonary Medicine, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Randeep
authors.initials: R
authors.lastname: Guleria
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics* / Q000473:pathology; D066246:ErbB Receptors / Q000096:biosynthesis / Q000235:genetics*; D005091:Exons / Q000235:genetics; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007194:India; D008297:Male; D008875:Middle Aged; D009154:Mutation; D017422:Sequence Analysis, DNA / Q000379:methods
chemical_list: C512478:EGFR protein, human; D066246:ErbB Receptors