An observational study in Non-Small Cell Lung Cancer, sponsored by Faculty of Medicine of Tunis. Completed at 1 site in Tunisia. Per ClinicalTrials.gov, last updated 2026-03-19.
Sponsored by Faculty of Medicine of Tunis · Observational
The goal of this retrospective observational study is to assess the clinical utility of plasma-based EGFR testing for detection and longitudinal monitoring of the acquired T790M resistance mutation in patients with advanced EGFR-mutated non-small cell lung cancer (NSCLC) treated with first- or second-generation EGFR tyrosine kinase inhibitors in routine clinical practice in Tunisia.
The main questions it aims to answer are:
Acquired resistance to first- and second-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in advanced EGFR-mutated non-small cell lung cancer (NSCLC) is most commonly mediated by the secondary EGFR T790M mutation. Identification of this resistance mechanism is clinically relevant, as it may guide subsequent treatment strategies. However, repeat tissue biopsy at disease progression is often limited by tumor inaccessibility, patient condition, or procedural risk. Plasma-based analysis of circulating tumor DNA (ctDNA) offers a minimally invasive alternative for molecular reassessment.
This retrospective real-world study evaluates the implementation of plasma EGFR testing for the detection of acquired T790M mutation in routine clinical practice in Tunisia. The study focuses on the detection rate of T790M at progression, the added value of repeated liquid biopsy sampling in initially negative cases, and the relationship between T790M emergence and baseline clinical or molecular characteristics.
In addition, longitudinal patterns of T790M appearance, persistence, or loss across serial plasma samples are explored to better understand resistance dynamics under TKI selective pressure. The association between T790M status and progression-free survival is also assessed.
By integrating molecular results with longitudinal clinical follow-up, this study seeks to characterize real-world patterns of acquired resistance and to evaluate the practical contribution of plasma-based EGFR testing to therapeutic decision-making.
7,620 studies on the registry are indexed under Carcinoma, Non-Small-Cell Lung; 1,838 are open to participants now.
This study's enrollment of 70 is below the median of 160 across 1,148 observational studies indexed under Carcinoma, Non-Small-Cell Lung.
Browse Carcinoma, Non-Small-Cell Lung studies →Faculty of Medicine of Tunis is the lead sponsor of 5 studies on the registry; 4 are open to participants now.
Counted across the registry records on this site, refreshed daily.
This study included patients with advanced non-small cell lung cancer consulting in different hospitals in Tunisia (The Military Hospital of Tunis, Salah Azaiez Institute, Abderhamen Mami Hospital, Jendouba Hospital, Charles Nicolle Hospital of Tunis...) and referred to the Pathology Department of Charles Nicolle Hospital of Tunis for EGFR T790M monitoring using liquid biopsy.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Detection rate of EGFR T790M mutation in plasma at disease progression
Proportion of patients with detectable T790M in plasma at the time of radiological progression.
Time frame: From initiation of first- or second-generation EGFR-TKI therapy until the first documented radiological disease progression at which plasma EGFR T790M testing is performed, assessed up to 36 months.
Proportion of participants with newly detected EGFR T790M on repeat liquid biopsy after an initial negative plasma result
Incremental T790M detection rate in patients with initially negative plasma results who underwent additional testing.
Time frame: From the initial negative plasma EGFR T790M result at radiological disease progression until detection of T790M on repeat liquid biopsy testing during follow-up, assessed up to 36 months.
Association of T790M emergence with baseline characteristics
Correlation of T790M status with clinical and molecular features at baseline.
Time frame: Baseline defined at the time of initiation of first- or second-generation EGFR-TKI therapy, before treatment exposure
Progression-free survival by T790M status
Comparison of progression-free survival in patients with versus without T790M detected in plasma.
Time frame: From initiation of first- or second-generation EGFR-TKI therapy until the first radiologically confirmed disease progression, assessed up to 36 months.
This study is completed, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Carcinoma, Non-Small-Cell Lung →
Faculty of Medicine of Tunis