ESR1 Mutation Detection and Dynamicsin Meningeal Carcinomatosis in BreastCancer
- Author:
Marcela CARAUSU
1
;
Samia MELAABI
;
Jean-Yves PIERGA
;
François-Clément BIDARD
;
Luc CABEL
Author Information
- Publication Type:Case Report
- From:Journal of Breast Cancer 2020;23(2):218-223
- CountryRepublic of Korea
- Language:English
- Abstract: ESR1 mutation is frequently encountered in hormone receptor (HR)-positive, humanepidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer (MBC),especially after aromatase inhibitor (AI) therapy, as a mechanism of resistance to endocrinetherapy. Circulating tumor DNA-based detection of ESR1 mutation in plasma has beendemonstrated as a prognostic and predictive factor for poor outcomes in subsequent AItherapy. In this case report, for the first time, we describe the detection of ESR1 mutation(p.Tyr537Ser) only in the cerebrospinal fluid (CSF) and not in the plasma of a patient withisolated leptomeningeal progression who was treated with AI for HR-positive, HER2-negativeMBC (bone metastasis only). Circulating tumor DNA levels also appeared to be correlatedwith clinical evolution. We suggest that in the presence of isolated leptomeningeal metastasisand when tamoxifen or AI has been prescribed for HR-positive MBC, CSF should be screenedfor ESR1 mutations to potentially adjust systemic treatment.
