Related Experiment Video
Updated: Feb 13, 2026
A Standardized Liquid Biopsy Preanalytical Protocol for Downstream Circulating-Free DNA Applications
Published on: September 16, 2022
Effective osimertinib treatment in a patient with discordant T790 M mutation detection between liquid biopsy and
Isa Mambetsariev1, Lalit Vora2, Kim Wai Yu3
1Department of Medical Oncology and Therapeutics Research, City of Hope Comprehensive Cancer Center and Beckman Research Institute, 1500 E Duarte Rd, Duarte, CA, 91010-3000, USA.
Background:
We report the successful treatment of the patient with osimertinib 80 mg/day following disease progression and a discordance in the detection of a mechanism of resistance epithelial growth factor receptor (EGFR) T790 M between liquid biopsy and tissue biopsy methods.
Case Presentation:
A 57-year-old Hispanic male patient initially diagnosed with an EGFR 19 deletion positive lung adenocarcinoma and clinically responded to initial erlotinib treatment. The patient subsequently progressed on erlotinib 150 mg/day and repeat biopsies both tissue and liquid were sent for next-generation sequencing (NGS). A T790 M EGFR mutation was detected in the blood sample using a liquid biopsy technique, but the tissue biopsy failed to show a T790 M mutation in a newly biopsied tissue sample. He was then successfully treated with osimertinib 80 mg/day, has clinically and radiologically responded, and remains on osimertinib treatment after 10 months.
Conclusions:
Second-line osimertinib treatment, when administered at 80 mg/day, is both well tolerated and efficacious in a patient with previously erlotinib treated lung adenocarcinoma and a T790 M mutation detected by liquid biopsy.
Insights
This study shows osimertinib effectively treated lung cancer resistant to erlotinib. Liquid biopsy detected a resistance mutation missed by tissue biopsy, guiding successful treatment.
Area of Science:
- Oncology
- Molecular Biology
- Genetics
Background:
- Non-small cell lung cancer (NSCLC) treatment often involves targeted therapies.
- Epidermal Growth Factor Receptor (EGFR) mutations are key targets in NSCLC.
- Resistance to EGFR inhibitors like erlotinib necessitates understanding resistance mechanisms.
Observation:
- A patient with EGFR 19 deletion NSCLC progressed on erlotinib.
- Next-generation sequencing (NGS) revealed a discrepancy: T790M mutation detected in liquid biopsy but not tissue biopsy.
- This discordance highlights challenges in resistance mutation detection.
Findings:
- Second-line treatment with osimertinib (80 mg/day) was initiated based on liquid biopsy results.
- The patient showed significant clinical and radiological response to osimertinib.
- Osimertinib treatment was well-tolerated and maintained for 10 months.
Implications:
- Liquid biopsy can be a valuable tool for detecting resistance mutations missed by tissue biopsy.
- Osimertinib is an effective second-line therapy for NSCLC with T790M resistance mutations.
- Personalized treatment strategies informed by comprehensive genomic profiling improve patient outcomes.
Related Concept Videos
01:39Mutations
01:35Mutations
Chromosomal Alterations Are Large-Scale Mutations
While point mutations are changes in a single nucleotide in...
00:36Viral Mutations
01:27Pharmacodynamics in Geriatric Patients: Effects of Age
01:18Effects of EDTA on End-Point Detection Methods
In the visual method, metal-ion indicators (metallochromic dyes), which have distinct colors in their free and complex forms, are added to the mixture to signal the titration's end point. They form stable complexes with metal ions, but these complexes are weaker than the corresponding metal–EDTA complexes. As a...
01:09Mutation, Gene Flow, and Genetic Drift