A Novel MYH9-RET Fusion Occurrence and EGFR T790M Loss as an Acquired Resistance Mechanism to Osimertinib in a Patient with Lung Adenocarcinoma: A Case Report.

Content Provider	Europe PMC
Author	Sun, Yanwei Pei, Lina Luo, Ningning Chen, Dongsheng Meng, Lingxin
Copyright Year	2020
Abstract	BackgroundOsimertinib is a novel and irreversible epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) targeting EGFR sensitive mutations and EGFR exon20 p.T790M mutation, which demonstrated superior progression-free survival (PFS) and overall survival (OS).Case PresentationWe report a patient with lung adenocarcinoma harboring EGFR exon 19 deletion mutant treatment with icotinib. After 6 months, she developed EGFR exon20 p.T790M and then the patient received osimertinib treatment. A novel MYH9 (exon41)-RET (exon12) fusion and EGFR exon20 p.T790M loss were identified using plasma circulation tumor DNA (ctDNA) after osimertinib treatment, which led to rapid progression after osimertinib five months and suggested a potential resistance mechanism.ConclusionOur findings expanded the spectrum of RET arrangement types and provided the basis for this hypothesis: acquired RET rearrangement and EGFR exon20 p.T790M loss potentially serve an additional resistance mechanism to osimertinib in EGFR-mutated non-small-cell lung cancer (NSCLC).
Page Count	5
Journal	Oncotargets and Therapy
Volume Number	13
PubMed Central reference number	PMC7646409
PubMed reference number	33173309
e-ISSN	11786930
DOI	10.2147/ott.s267524
Language	English
Publisher	Dove Medical Press
Publisher Date	2020-11-02
Access Restriction	Open
Rights License	This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution – Non Commercial (unported, v3.0) License (http://creativecommons.org/licenses/by-nc/3.0/). By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms (https://www.dovepress.com/terms.php). © 2020 Sun et al.
Subject Keyword	MYH9-RET fusion EGFR exon20 p.T790M loss lung adenocarcinoma acquired resistance osimertinib
Content Type	Text
Resource Type	Article
Subject	Pharmacology (medical) Oncology