Chenhui Ma¹  Yanwen Yao¹  Qian Li¹  Yafang Liu²  Yong Song¹

¹Nanjing, China Jinling Hospital, Nanjing University School of Medicine Department of Respiratory Medicine. ²Nanjing, China Jinling Hospital, Nanfang Medical University,Department of Respiratory Medicine.

Objective: In2011, the International Association for the Study of Lung Cancer, AmericanThoracic Society and European Respiratory Society (IASLC/ATS/ERS) proposed thenew lung adenocarcinoma histologic classification. The purpose of this meta-analysisis to determine the relationship between EGFR mutation states and differentpredominant histologic subtypes. We searched the literatures which studyingEGFR mutation states and different histologic subtypes of lung adenocarcinomain PubMed, EMBASE database and Cochrane Library literature from January, 2011to February, 2015. Nine studies with total 1761 patients providing detailedlung adenocarcinoma classification and EGFR mutation data were included in thismeta-analysis. The detailed numbers of patients in different subtypes, differentEGFR mutation states were extractedand estimated using a random-effect model.The micropapillary predominant subtype was found to be tended with EGFRmutation (RR=1.37, 95%CI=1.08-1.74, P=0.011). On the contrary, the solidpredominant subtype has a low EGFR mutation frequency (RR=0.74, 95%CI=0.59-0.93,P=0.009). Obvious correlation with EGFR mutation states is not foundamong other histologic subtypes. In conclusion, this meta-analysis suggeststhat the frequency of EGFR mutations varies according to the new IASLC/ATS/ERS adenocarcinomaclassification. Method: In 2011, the International Association for theStudy of Lung Cancer, American Thoracic Society and European Respiratory Society(IASLC/ATS/ERS) proposed the new lung adenocarcinoma histologic classification.The purpose of this meta-analysis is to determine the relationship between EGFRmutation states and different predominant histologic subtypes. We searched the literatureswhich studying EGFR mutation states and different histologic subtypes of lungadenocarcinoma in PubMed, EMBASE database and Cochrane Library literature fromJanuary, 2011 to February, 2015. Nine studies with total 1761 patientsproviding detailed lung adenocarcinoma classification and EGFR mutation datawere included in this meta-analysis. The detailed numbers of patients indifferent subtypes, different EGFR mutation states were extractedand estimatedusing a random-effect model. The micropapillary predominan tsubtype was foundtobe tended with EGFR mutation (RR=1.37, 95%CI=1.08-1.74, P=0.011). Onthe contrary, the solid predominant subtype has a low EGFR mutation frequency(RR=0.7, 95%CI=0.59-0.93, P=0.009). Obvious correlation with EGFRmutation states is not found among other histologic subtypes. In conclusion, thismeta-analysis suggests that the frequency of EGFR mutations varies according tothe new IASLC/ATS/ERS adenocarcinoma classification. Result: In 2011, theInternational Association for the Study of Lung Cancer, American ThoracicSociety and European Respiratory Society (IASLC/ATS/ERS) proposed the new lungadenocarcinoma histologic classification. The purpose of this meta-analysis isto determine the relationship between EGFR mutation states and differentpredominant histologic subtypes. We searched the literatures which studyingEGFR mutation states and different histologic subtypes of lung adenocarcinomain PubMed, EMBASE database and Cochrane Library literature from January, 2011to February, 2015. Nine studies with total 1761 patients providing detailedlung adenocarcinoma classification and EGFR mutation data were included in thismeta-analysis. The detailed numbers of patients in different subtypes, differentEGFR mutation states were extractedand estimated using a random-effect model.The micro papillary predominant subtype was found to be tended with EGFRmutation (RR=1.37, 95%CI=1.08-1.74, P=0.011). On the contrary, the solidpredominant subtype has a low EGFR mutation frequency (RR=0.74, 95%CI=0.59-0.93,P=0.009). Obvious correlation with EGFR mutation states is not foundamong other histologic subtypes. In conclusion, this meta-analysis suggeststhat the frequency of EGFR mutations varies according to the new IASLC/ATS/ERS adenocarcinomaclassification. Conclusion: In 2011, the International Association forthe Study of Lung Cancer, American Thoracic Society and European RespiratorySociety (IASLC/ATS/ERS) proposed the new lung adenocarcinoma histologicclassification. The purpose of this meta-analysis is to determine the relationshipbetween EGFR mutation states and different predominant histologic subtypes. Wesearched the literatures which studying EGFR mutation states and differenthistologic subtypes of lung adenocarcinoma in PubMed, EMBASE database andCochrane Library literature from January, 2011 to February, 2015. Nine studieswith total 1761 patients providing detailed lung adenocarcinoma classificationand EGFR mutation data were included in this meta-analysis. The detailednumbers of patients in different subtypes, different EGFR mutation states wereextracted and estimated using a random-effect model. The micro papillarypredominant subtype was found to be tended with EGFR mutation (RR=1.37, 95%CI=1.08-1.74,P=0.011). On the contrary, the solid predominant subtype has a low EGFR mutationfrequency (RR=0.74, 95%CI=0.59-0.93, P=0.009). Obvious correlation withEGFR mutation states is not found among other histologic subtypes. Inconclusion, this meta-analysis suggests that the frequency of EGFR mutationsvaries according to the new IASLC/ATS/ERS adenocarcinoma classification.

KeyWords: NSCLC EGFR mutation