Is T790M an exon 20 mutation?
The secondary mutation in exon 20, T790M, detected in approximately 50% of re-biopsy samples after TKI therapy, is regarded as the most common cause of acquired resistance to TKIs (6).
What is T790M mutation lung cancer?
The T790M mutation is present in about half of the lung cancer patients with acquired resistance, and reported to act by increasing the affinity of the receptor to adenosine triphosphate, relative to its affinity to TKIs.
What is EGFR exon 20 insertion mutation?
Abstract. Background: Epidermal growth factor receptor gene (EGFR) exon 20 insertion (ex20-ins) mutations are an uncommon and heterogeneous group of non-small cell lung cancers (NSCLCs), resistant to conventional EGFR tyrosine kinase inhibitors (TKIs).
What causes EGFR exon 20?
The EGFR exon 20 mutation in non–small cell lung cancer (NSCLC) is a progressive and genetic disease that can occur regardless of smoking history, with response to conventional chemotherapy tending to be very poor in these populations, said Christopher Arendt, PhD, head of the Oncology Therapeutic Area Unit at Takeda.
How do you test for T790M mutation?
ctDNA testing provides a rapid, minimally invasive blood testing alternative to traditional biopsy or resection tissue analysis of EGFR T790M mutation status in non-small cell lung adenocarcinoma.
Where is the T790M mutation?
However, patients who develop resistance to TKI treatment often acquire a somatic resistance mutation (T790M) located in the catalytic cleft of the epidermal growth factor receptor (EGFR) enzyme.
How common is exon 20 insertion mutation?
However, reports regarding the incidence and clinical outcome of NSCLC patients with these insertions were initially limited. The frequency of EGFR exon 20 insertions has since been reported as being between 4 and 10% of all observed EGFR mutations in NSCLC.
What does EGFR exon 19 deletion mean?
Epidermal growth factor receptor (EGFR) exon 19 deletion (E19del) is the most common activating mutation in advanced non–small cell lung cancer (NSCLC) and associates with the sensitivity of EGFR tyrosine kinase inhibitors (TKIs) treatment.
What is treatment for EGFR mutation?
Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are the first-line treatment of choice for patients with EGFR mutation-positive non-small-cell lung cancer (NSCLC).
How is EGFR mutation detected?
In clinical practice, EGFR mutations are routinely detected using DNA extracted from primary or metastatic tumour tissue obtained during tumour biopsy or resection, which is typically formalin fixed and paraffin embedded (FFPE) (Ellison et al, 2013; Jung, 2013).
Which exon is T790M?
T790M mutation in exon 20 is usually associated with secondary resistance to EGFR tyrosine kinase inhibitors therapy but is also present in treatment-naïve patients. The frequency for baseline T790M mutation varies from 4 to 35% according to the detection method used.
What is exon 20 mutation?
Background: Epidermal growth factor receptor gene (EGFR) exon 20 insertion (ex20-ins) mutations are an uncommon and heterogeneous group of non-small cell lung cancers (NSCLCs), resistant to conventional EGFR tyrosine kinase inhibitors (TKIs).
What is T790M?
A secondary point mutation that substitutes methionine for threonine at amino acid position 790 (T790M) is a molecular mechanism that produces a drug-resistant variant of the targeted kinase.
What is the T790M variant of EGFR?
Genetic variant. T790M, also known as Thr790Met, is a gatekeeper mutation of the epidermal growth factor receptor (EGFR). The mutation substitutes a threonine (T) with a methionine (M) at position 790 of exon 20, affecting the ATP binding pocket of the EGFR kinase domain.
What is the T790M mutation?
From Wikipedia, the free encyclopedia T790M, also known as Thr790Met, is a gatekeeper mutation of the epidermal growth factor receptor (EGFR). The mutation substitutes a threonine (T) with a methionine (M) at position 790 of exon 20, affecting the ATP binding pocket of the EGFR kinase domain.