Since the advent of targeted therapy in lung cancer, in settings where it is not possible to send for molecular testing of lung adenocarcinoma, immunohistochemistry for EGFR mutation-specific antibodies can be used as an alternative for detection of EGFR mutation. Materials and methods: 50 lung adenocarcinoma cases were screened at the Medical University of Graz. 19 cases in which molecular test as well as immunohistochemistry were positive for EGFR mutation. Cases where immunohistochemistry

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... ults and molecular test for the E-746-A750 deletion and the L858 mutation were positive, were considered true positives. Similarly, false positives, true negatives, and false negatives were determined. Results: The mean age of the patients was 78.6 yrs. Among 19 cases, 7 were positive for E-746-A750 deletion (7/19, 36%), among which 4 cases also showed positivity with IHC. 4 were positive for the L858 mutation (4/19, 21%), among which 3 also showed positivity with immunohistochemistry. The rest of the 8 cases were positive for EGFR mutation in other loci. The sensitivity and specificity of the immunohistochemistry test of antibody specific to E-746-A750 exon 19 deletion was 100% and 80% respectively. The sensitivity and specificity of the IHC test of Ab specific to L858 mutation was 75%, and 100% respectively. Conclusions: Our results have been comparable to previous studies. However, our sample size was a limitation. It can still be concluded that immunohistochemistry can be a diagnostic option in low resource settings, and can aid in ensuring that patients with a positive antibody test get targeted therapy.