Prognostic Factors in Japanese EGFR Mutation-Positive Non-Small-Cell Lung Cancer: A Real-World Single-Center Retrospective Cohort Study.

The patients who were T790M-positive in the first-line treatment with first or second-generation EGFR-TKIs and were given osimertinib as the second or later line treatment had a better prognosis than the patients who were T790M-negative in the first-line treatment with first or second-generation EGFR-TKIs and could not receive osimertinib.