Cytoplasmic ERβ1 expression is associated with survival of patients with Stage IV lung adenocarcinoma and an EGFR mutation at exon 21 L858R subsequent to treatment with EGFR-TKIs.
We report a case of a 38-year-old woman who was diagnosed with stage IV lung adenocarcinoma, harboring an epidermal growth factor receptor (EGFR) L858R mutation on exon 21 and a T790 M mutation on exon 20.
Patients in stage IV lung adenocarcinoma with MPEs at initial diagnosis have shorter overall survival and higher EGFR mutation rate, especially for L858R, than patients who develop MPEs following disease progression.