OBJECTIVE: To explore the clinical efficacy and safety of osimertinib in the treatment of epidermal growth factor receptor（EGFR） gene mutation-positive non-small cell lung cancer（NSCLC） patients in the real world. METHODS: A total of 52 NSCLC patients with EGFR gene mutation treated with osimertinib in the First People’s Hospital of Yunnan from Jan. 2019 to Mar. 2021 were extracted as the research objects

the efficacy and safety of osimertinib were evaluated. RESULTS: Among the 52 patients

the overall disease control rate was 90.4%（47/52）

the median progression-free survival was 12.0 months（95%CI: from 8.2 to 15.8 months）

and the median overall survival was 21.0 months（95%CI: from 13.0 to 28.9 months）. The main adverse drug reactions were diarrhea（44.2%

23/52）

dry skin（25.0%

13/52）

rash（23.1%

12/52）

paronychia（21.2%

11/52） and nausea and vomiting（21.2%

11/52）. The incidence of adverse drug reactions of grade Ⅲ and above was 15.4%（8/52）. CONCLUSIONS: In the real world

the efficacy of osimertinib in the treatment of EGFR gene mutation-positive NSCLC patients is significant

with higher safety.