Which Tyrosine Kinase Inhibitor Must We Apply Before? A Case Report of Crizotinib-resistant Patient with Concomitant EGFR and EML4-ALK Gene Mutations

ABSTRACT The concomitant epidermal growth factor receptor (EGFR) mutation and anaplastic lymphoma kinase (ALK) translocations in lung adenocancers are very rare scenarios. Until now, 42 cases described in the literature have all been treated by different drugs. There is no overall consensus regarding the treatment for this adenocarcinoma subgroup. We report here a case of lung adenocarcinoma with concomitant EGFR mutation in exon 21 (L858R) and ALK rearrangement in primary tumour, EGFR mutation in exon 21 (L858R) and no ALK rearrangement in its synchronous metastasis. We treated this patient with crizotinib as the second-line therapy (after the first line docetaxel-cisplatin chemotherapy), but no response was obtained. The therapeutic choice for the lung adenocancer patients with concomitant EGFR mutation and ALK rearrangement is unclear. Examination of c-ros oncogene 1 mutation can be used as an indicator in the prediction of the crizotinib treatment success. The ALK mutation may not responsible for the resistance to EGFR-tyrosine kinase inhibitors (TKI), and EGFR-TKI can be initiated to EGFR and ALK dual mutant patients as the first treatment.