Favorable response to icotinib in a lung cancer patient with a special mutation at exon 19 of epidermal growth factor receptor.

Many studies have illustrated that two types of mutation - deletions in exon 19 and a point mutation in exon 21 (L858R) - have been reported to comprise up to 90% of all activating epidermal growth factor receptor (EGFR) mutations. A point mutation at exon 19 is a rare mutation, and to date there have been no reports investigating the sensitivities of EGFR-tyrosine kinase inhibitors (TKIs) to the mutation. In this case report, we have demonstrated a special mutation, a point mutation at c.2279T>C (p.L760P) in exon 19 of EGFR, which has responded favorably to icotinib in a lung adenocarcinoma patient with brain metastasis. Icotinib is a new type of oral EGFR-TKI developed in China and is the first EGFR-TKI in Asia. Icotinib has the potential to improve the prognosis of lung adenocarcinoma patients and with less toxic-effect.