Abstract 496P
Background
Indication for treatment with osimertinib after first/second generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) resistance depends on T790M mutation detected by re-biopsy. REMEDY trial consisting many cases using plasma biopsy revealed osimertinib introduction rate of approximately 25 percent in EGFR-mutant non-small cell lung cancer (NSCLC) patients pretreated with first/second generation EGFR-TKIs. The aim of study is to analyze the data on clinical practice of our hospital, where histological re-biopsy is actively carried out multiple times.
Methods
We retrospectively reviewed our electronic medical records of EGFR-mutant NSCLC patients to examine osimertinib introduction rate and associated outcomes.
Results
Among 95 patients with EGFR-mutant NSCLC, 73 patients received first/second generation EGFR-TKIs. Of 57 progressive disease patients, 50 patients (57/50: 87%) underwent re-biopsy. T790M was detected in 36 patients (36/50: 72%) and osimertinib was introduced in 35 patients (35/50: 70%). Among 36 patients harboring T790M mutation: histological re-biopsy was performed in 21 patients (21/36: 58%); cytology in 12 patients (12/36: 33%); blood biopsy in three patients (3/36: 8.3%). T790M was detected by first re-biopsy in 14 patients (14/36: 39%), and by second or subsequent re-biopsy 22 patients (22/36: 61%). The median overall survival (OS) in osimertinib induction patients was not reached (95% CI, 64.2-not reached) while in non- osimertinib patients median OS was 92.9 months (95% CI, 22.5-not reached) (p = 0.0173). Five year survival rates were 77% and 52%, respectively.
Conclusions
Higher osimertinib introduction rate was achieved by multiple repeated re-biopsy after first/second generation EGFR-TKIs, and its high introduction rate could contribute to better prognosis of EGFR-mutant NSCLC.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Kobe Minimally Invasive Cancer Center.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
380P - Ventricular–Subventricular zone involvement: A predictive factor for survival in glioblastoma
Presenter: Vibhay Pareek
Session: Poster display session
Resources:
Abstract
381P - XKR8 is a promising potential prognostic marker in glioblastoma multiforme patients
Presenter: Kristina Havrysh
Session: Poster display session
Resources:
Abstract
383P - Screening of prognostic molecular biomarker for resectable pancreatic cancer
Presenter: Yonggang Peng
Session: Poster display session
Resources:
Abstract
384P - Prevalence of abnormal microsatellite instability test among ovary and endometrial cancer patients
Presenter: Min Kyu Kim
Session: Poster display session
Resources:
Abstract
385P - Identifying CASP8 polymorphisms associated with breast cancer risk in an Iranian population
Presenter: Alireza Pasdar
Session: Poster display session
Resources:
Abstract
386P - Unusual folding of NaPi2b transporter extramembrane domain 4 during malignant transformation
Presenter: Leysan Minigulova
Session: Poster display session
Resources:
Abstract
387P - 5-years conditional disease free survival and overall survival for breast cancer patients in South Korea
Presenter: Jee hyun Ahn
Session: Poster display session
Resources:
Abstract
388P - To identify circulating tumour cells by machine learning approach
Presenter: Yuebin Liang
Session: Poster display session
Resources:
Abstract
389P - The establishment of patient-derived organoid models and drug response of resectable non-small cell lung cancer
Presenter: Jing-Hua Chen
Session: Poster display session
Resources:
Abstract
395P - Filipinos and lung cancer: An infodemiological assessment using Google trends from 2009 to 2019
Presenter: Lance Isidore Catedral
Session: Poster display session
Resources:
Abstract