Oops, you're using an old version of your browser so some of the features on this page may not be displaying properly.

MINIMAL Requirements: Google Chrome 24+Mozilla Firefox 20+Internet Explorer 11Opera 15–18Apple Safari 7SeaMonkey 2.15-2.23


19P - Predictors of Osimertinib Response at Second-line Treatment in EGFR Mutant Non-small Cell Lung Cancer Patients with Acquired T790M Resistance Mutation


06 Oct 2021




Izzet Dogan


Annals of Oncology (2021) 32 (suppl_6): S1345-S1371. 10.1016/annonc/annonc740


I. Dogan1, M. Gürbüz2, N. Paksoy3, N. Khanmamadov3, S. Vatansever3, P. Saip3, A. Demirkazik2, A. Aydiner3

Author affiliations

  • 1 Istanbul University Institute of Oncology, Istanbul/TR
  • 2 Ankara University Faculty of Medicine, 6100 - Ankara/TR
  • 3 Istanbul University Institute of Oncology, 34093 - Istanbul/TR

Abstract 19P


T790M resistance mutation is developed in about half of the metastatic lung cancer patients with EGFR mutations and treated with EGFR inhibitors. Osimertinib is effective for treating patients who had acquired T790M resistance mutation. The purpose of this study was to assess the predictors of osimertinib response in metastatic lung cancer patients who had acquired T790M resistance mutations.


We evaluated the clinicopathological and treatment features of the patients who acquired T790M resistance mutations and received osimertinib retrospectively. We used the Kaplan-Meier method, Cox regression analysis, and logistic regression analysis for statistical analysis.


Forty-five patients were included in the study. The median age was 59 (range, 33-79). Twenty-six patients (57.8%) were female. Forty patients (88.9%) were de-novo metastatic. Thirteen patients (28.9%) had metastasis in three or more organs. Twelve patients (26.7%) had brain metastasis and six patients (13.3%) had liver metastasis. The objective response (complete or partial) rate was 62.2% with a median of 19.3 (95 CI %, 8.5-30) months progression-free survival. In logistic regression analysis, we found that age, gender, EGFR mutation type, brain metastasis, and type of previous therapies were not statistically significant for the response of osimertinib.


This study showed that osimertinib response was not related to clinicopathological features in metastatic lung cancer patients who had acquired T790M resistance mutation.

Legal entity responsible for the study

The authors.


Has not received any funding.


All authors have declared no conflicts of interest.

This site uses cookies. Some of these cookies are essential, while others help us improve your experience by providing insights into how the site is being used.

For more detailed information on the cookies we use, please check our Privacy Policy.

Customise settings