The relationship between EGFR mutation and metastasis pattern in lung adenocarcinoma

Abstract

Aim: The metastatic pattern of non-small cell lung cancer (NSCLC) has been described in several studies. Frequent metastatic sites are lung, liver, bone, surrenal, and brain. Hypotheses were speculated to explain the tendency of specific sites. Over-expression of EGFR alters the biology and tumoral behavior. The mutations of EGFR mainly occur in exon 19, and 21and could lead the way through the tumor growth and metastasis. We try to elucidate the relationship between EGFR mutation and metastatic pattern. Material and Method: In this retrospective nested case-control study, one hundred and five patients diagnosed with lung adenocarcinoma included who had EGFR mutation status and imaging studies at the time of diagnosis. Results: The metastatic pattern was not different between EGFR mutant and wild type patients. There was no statistical difference in terms of survival between EGFR mutant and wild type patients (p = 0.25). The OS according to the organ metastasis between EGFR mutant and wild type group was not significant except liver. The EGFR mutant patients with liver metastasis had better survival compared with wild type patients (p = 0.04). Also, the multiplicity and solidarity of the metastatic tumors were compared in metastatic organs. There was no significant difference between groups. The subsequent EGFR mutation type was not related to the metastatic pattern. Conclusion: The incidence of the metastatic sites was not different between EGFR mutant and wild type patients in our study. In contrast to the literature, liver metastasis found to be related to improved OS. Keywords: Non-small cell lung cancer, Adenocarcinoma, EGFR mutation, Metastasis pattern