EGFR and lung adenocarcinoma: A recent study 62 conducted in 835 patients, who underwent complete surgical resection for lung adenocarcinoma without EGFR TKIs as a neoadjuvant or adjuvant therapy, showed that patients with 19del had a significantly higher incidence of extrathoracic recurrence than patients with L858R (p =0.004), and the L858R group had a significantly longer recurrence-free survival than the WT group (p < 0.001) and the 19del group (p = 0.016).