[Molecular pathology of lung adenocarcinomas, EGFR T790M resistance mutation study].

Aim: In our institute, we have been testing EGFR T790M resistance mutations since 2019, which is the most common resistance mutation that develops during first-line, second- line EGFR TKI treatment of EGFR mutant lung adenocarcinomas. The importance of this study is that the identification of this mutation will allow the use of an effective third-generation TKI. In this article, we report on studies from January 2022 to August 2024, compared with our results from the 2019-2021 period.

Methods: 380, predominantly blood samples from 222 patients were tested during the present period using Super- ARMS EGFR Mutation Detection Kit (AmoyDx).

Results: EGFR mutations were identified in 57% of all samples in the primary tumours, with a 38.3% frequency of T790M mutation.

Conclusions: Our results were similar to the previous period. The number of rebiopsies was essentially unchanged compared to the 2019-2021 period, which may be the main reason why we were able to identify the mutation in a lower percentage compared to the T790M hit rate described in the literature.