We previously reported clinicopathological findings of patients with lung cancer harboring the EML4-ALK fusion gene.     ///    EML4-ALK was detected by a reverse transcription polymerase-chain reaction and by the newly established criteria and algorithm using a fluorescence in situ hybridization method.    ///    EML4-ALK was detected by a reverse transcription polymerase-chain reaction and by the newly established criteria and algorithm using a fluorescence in situ hybridization method.     ///    We investigated EML4-ALK in tumors from 581 patients.    ///     To develop an easy-to-use technique for EML4-ALK detection and establish the effective selection of candidates for screening.     ///    "Of the 27 patients, 8 (29.6%) had EML4-ALK. "    ///    "8 (1.3%) tumors had EML4-ALK, EGFR, KRAS, and ERBB2 mutations, which were mutually exclusive and were detected in 191 (32.8%), 56 (9.6%), and 11 (1.8%) tumors, respectively. "    ///    "Anaplastic lymphoma kinase inhibitors have therapeutic effects in lung cancer patients with EML4-ALK, accounting for merely 1%-5% of lung cancers. "