Tuesday 25 June 2013
Patients with lung cancer who respond to gefitinib have been reported to have somatic mutations consisting of deletions in exon 19 and the L858R mutation in exon 21 of the epidermal growth factor receptor (EGFR) gene.
Lung cancers harboring the EGFR L858R mutation have been reported to be responsive to gefitinib.
The studies of cells expressing L858R revealed increased gefitinib sensitivity in vitro.
A patient with gefitinib-resistant lung adenocarcinoma harboring both T790M and L858R at diagnosis has also been described.
- In addition, a second mutation (T790M) in exon 20 is also associated with acquired resistance to gefitinib in initially gefitinib-sensitive patients.