[Mutation-specific antibodies for detection of epidermal growth factor receptor mutations in patients with lung adenocarcinoma].

OBJECTIVE:To examine the sensitivity and specificity of the two epidermal growth factor receptor hotspot mutation antibodies-delE746-A750 and L858R in lung adenocarcinoma, and to discuss the value of the two antibodies for detecting these two "classic mutations" by immunohistochemistry. METHODS:With Q-scoring assessment and ROC curve analysis,immunohistochemistry was used to screen a panel of 309 paraffin-embedded non-small cell lung cancer(NSCLC) tumor samples, of which EGFR gene mutational status was previously documented by PCR-DNA sequencing. RESULTS:Three hundred and nine NSCLC tumor samples conclude 92 NSCLC cases with 19delE746-A750 and 110 with 21L858R. Using DelEGFR antibody to detect 19delE746-A750 demonstrated sensitivity and specificity of 84.8% (78/92) and 77.6% (83/107), respectively. Choosing the best cut-off value of 85.00, it achieved the maximum area under the curve (AUC:0.885). L858R antibody to detect 21L858R showed sensitivity and specificity of 94.5% (104/110) and 62.5% (55/88), respectively. Choosing the best cut-off value of 97.50, it achieved the maximum area under the curve (AUC:0.924). CONCLUSION:By using Q-scoring assessment and ROC curve analysis, the two antibodies (delEGFR and L858R) can been used to identify EGFR gene mutations present in lung adenocarcinomas.